Write the CHANGELOG for 0.15.1

This is in the latest 0.15, and when forwarding path completions to
jedi, print a lot of stuff on the screen.

.coveragerc

@@ -3,8 +3,6 @@ omit =
     jedi/_compatibility.py
     jedi/evaluate/compiled/subprocess/__main__.py
     jedi/__main__.py
-    # Is statically analyzed and not actually executed.
-    jedi/evaluate/jedi_typing.py
     # For now this is not being used.
     jedi/refactoring.py
 

.travis.yml

@@ -15,9 +15,6 @@ env:
   - JEDI_TEST_ENVIRONMENT=37
 
 matrix:
-  allow_failures:
-    - python: pypy
-    - python: 3.8-dev
   include:
     - python: 3.6
       env:

AUTHORS.txt

@@ -52,5 +52,6 @@ Tobias Rzepka (@TobiasRzepka)
 micbou (@micbou)
 Dima Gerasimov (@karlicoss) <karlicoss@gmail.com>
 Max Woerner Chase (@mwchase) <max.chase@gmail.com>
+Johannes Maria Frank (@jmfrank63) <jmfrank63@gmail.com>
 
 Note: (@user) means a github user name.

CHANGELOG.rst

@@ -3,6 +3,34 @@
 Changelog
 ---------
 
+0.15.1 (2019-08-13)
++++++++++++++++++++
+
+- Small bugfix and removal of a print statement
+
+0.15.0 (2019-08-11)
++++++++++++++++++++
+
+- Added file path completions, there's a **new ``Completion.type``** ``path``,
+  now. Example: ``'/ho`` -> ``'/home/``
+- ``*args``/``**kwargs`` resolving. If possible Jedi replaces the parameters
+  with the actual alternatives.
+- Better support for enums/dataclasses
+- When using Interpreter, properties are now executed, since a lot of people
+  have complained about this. Discussion in #1299, #1347.
+
+New APIs:
+
+- ``Definition.get_signatures() -> List[Signature]``. Signatures are similar to
+  ``CallSignature``. ``Definition.params`` is therefore deprecated.
+- ``Signature.to_string()`` to format call signatures.
+- ``Signature.params -> List[ParamDefinition]``, ParamDefinition has the
+  following additional attributes ``infer_default()``, ``infer_annotation()``,
+  ``to_string()``, and ``kind``.
+- ``Definition.execute() -> List[Definition]``, makes it possible to infer
+    return values of functions.
+
+
 0.14.1 (2019-07-13)
 +++++++++++++++++++
 

conftest.py

@@ -140,3 +140,19 @@ def skip_pre_python38(environment):
         # This if is just needed to avoid that tests ever skip way more than
         # they should for all Python versions.
         pytest.skip()
+
+
+@pytest.fixture()
+def skip_pre_python37(environment):
+    if environment.version_info < (3, 7):
+        # This if is just needed to avoid that tests ever skip way more than
+        # they should for all Python versions.
+        pytest.skip()
+
+
+@pytest.fixture()
+def skip_pre_python35(environment):
+    if environment.version_info < (3, 5):
+        # This if is just needed to avoid that tests ever skip way more than
+        # they should for all Python versions.
+        pytest.skip()

docs/docs/features.rst

@@ -140,15 +140,8 @@ Most of the features in PEP-0484 are supported including the typing module
 (for Python < 3.5 you have to do ``pip install typing`` to use these),
 and forward references.
 
-Things that are missing (and this is not an exhaustive list; some of these
-are planned, others might be hard to implement and provide little worth):
+You can also use stub files.
 
-- annotating functions with comments: https://www.python.org/dev/peps/pep-0484/#suggested-syntax-for-python-2-7-and-straddling-code
-- understanding ``typing.cast()``
-- stub files: https://www.python.org/dev/peps/pep-0484/#stub-files
-- ``typing.Callable``
-- ``typing.TypeVar``
-- User defined generic types: https://www.python.org/dev/peps/pep-0484/#user-defined-generic-types
 
 **Sphinx style**
 

jedi/__init__.py

@@ -33,7 +33,7 @@ As you see Jedi is pretty simple and allows you to concentrate on writing a
 good text editor, while still having very good IDE features for Python.
 """
 
-__version__ = '0.14.1'
+__version__ = '0.15.1'
 
 from jedi.api import Script, Interpreter, set_debug_function, \
     preload_module, names
@@ -42,3 +42,6 @@ from jedi.api.environment import find_virtualenvs, find_system_environments, \
     get_default_environment, InvalidPythonEnvironment, create_environment, \
     get_system_environment
 from jedi.api.exceptions import InternalError
+# Finally load the internal plugins. This is only internal.
+from jedi.plugins import registry
+del registry

jedi/api/__init__.py

@@ -27,7 +27,7 @@ from jedi.api import interpreter
 from jedi.api import helpers
 from jedi.api.completion import Completion
 from jedi.api.environment import InterpreterEnvironment
-from jedi.api.project import get_default_project
+from jedi.api.project import get_default_project, Project
 from jedi.evaluate import Evaluator
 from jedi.evaluate import imports
 from jedi.evaluate import usages
@@ -144,7 +144,6 @@ class Script(object):
                              '(0-%d) for line %d (%r).' % (
                                  column, line_len, line, line_string))
         self._pos = line, column
-        self._path = path
 
         cache.clear_time_caches()
         debug.reset_time()
@@ -437,6 +436,7 @@ class Interpreter(Script):
     >>> print(script.completions()[0].name)
     upper
     """
+    _allow_descriptor_getattr_default = True
 
     def __init__(self, source, namespaces, **kwds):
         """
@@ -464,8 +464,10 @@ class Interpreter(Script):
             if not isinstance(environment, InterpreterEnvironment):
                 raise TypeError("The environment needs to be an InterpreterEnvironment subclass.")
 
-        super(Interpreter, self).__init__(source, environment=environment, **kwds)
+        super(Interpreter, self).__init__(source, environment=environment,
+                                          _project=Project(os.getcwd()), **kwds)
         self.namespaces = namespaces
+        self._evaluator.allow_descriptor_getattr = self._allow_descriptor_getattr_default
 
     def _get_module(self):
         return interpreter.MixedModuleContext(

jedi/api/classes.py

@@ -4,10 +4,9 @@ These classes are the much bigger part of the whole API, because they contain
 the interesting information about completion and goto operations.
 """
 import re
+import sys
 import warnings
 
-from parso.python.tree import search_ancestor
-
 from jedi import settings
 from jedi import debug
 from jedi.evaluate.utils import unite
@@ -38,6 +37,10 @@ def defined_names(evaluator, context):
     return [Definition(evaluator, n) for n in _sort_names_by_start_pos(names)]
 
 
+def _contexts_to_definitions(contexts):
+    return [Definition(c.evaluator, c.name) for c in contexts]
+
+
 class BaseDefinition(object):
     _mapping = {
         'posixpath': 'os.path',
@@ -150,6 +153,9 @@ class BaseDefinition(object):
         >>> defs[3]
         'function'
 
+        Valid values for are ``module``, ``class``, ``instance``, ``function``,
+        ``param``, ``path`` and ``keyword``.
+
         """
         tree_name = self._name.tree_name
         resolve = False
@@ -330,6 +336,8 @@ class BaseDefinition(object):
     @memoize_method
     def params(self):
         """
+        Deprecated! Will raise a warning soon. Use get_signatures()[...].params.
+
         Raises an ``AttributeError`` if the definition is not callable.
         Otherwise returns a list of `Definition` that represents the params.
         """
@@ -337,7 +345,10 @@ class BaseDefinition(object):
         # with overloading.
         for context in self._name.infer():
             for signature in context.get_signatures():
-                return [Definition(self._evaluator, n) for n in signature.get_param_names()]
+                return [
+                    Definition(self._evaluator, n)
+                    for n in signature.get_param_names(resolve_stars=True)
+                ]
 
         if self.type == 'function' or self.type == 'class':
             # Fallback, if no signatures were defined (which is probably by
@@ -384,6 +395,12 @@ class BaseDefinition(object):
         start_index = max(index - before, 0)
         return ''.join(lines[start_index:index + after + 1])
 
+    def get_signatures(self):
+        return [Signature(self._evaluator, s) for s in self._name.infer().get_signatures()]
+
+    def execute(self):
+        return _contexts_to_definitions(self._name.infer().execute_evaluated())
+
 
 class Completion(BaseDefinition):
     """
@@ -598,14 +615,37 @@ class Definition(BaseDefinition):
         return hash((self._name.start_pos, self.module_path, self.name, self._evaluator))
 
 
-class CallSignature(Definition):
+class Signature(Definition):
     """
-    `CallSignature` objects is the return value of `Script.function_definition`.
+    `Signature` objects is the return value of `Script.function_definition`.
     It knows what functions you are currently in. e.g. `isinstance(` would
     return the `isinstance` function. without `(` it would return nothing.
     """
+    def __init__(self, evaluator, signature):
+        super(Signature, self).__init__(evaluator, signature.name)
+        self._signature = signature
+
+    @property
+    def params(self):
+        """
+        :return list of ParamDefinition:
+        """
+        return [ParamDefinition(self._evaluator, n)
+                for n in self._signature.get_param_names(resolve_stars=True)]
+
+    def to_string(self):
+        return self._signature.to_string()
+
+
+class CallSignature(Signature):
+    """
+    `CallSignature` objects is the return value of `Script.call_signatures`.
+    It knows what functions you are currently in. e.g. `isinstance(` would
+    return the `isinstance` function with its params. Without `(` it would
+    return nothing.
+    """
     def __init__(self, evaluator, signature, call_details):
-        super(CallSignature, self).__init__(evaluator, signature.name)
+        super(CallSignature, self).__init__(evaluator, signature)
         self._call_details = call_details
         self._signature = signature
 
@@ -615,34 +655,60 @@ class CallSignature(Definition):
         The Param index of the current call.
         Returns None if the index cannot be found in the curent call.
         """
-        return self._call_details.calculate_index(self._signature.get_param_names())
-
-    @property
-    def params(self):
-        return [Definition(self._evaluator, n) for n in self._signature.get_param_names()]
+        return self._call_details.calculate_index(
+            self._signature.get_param_names(resolve_stars=True)
+        )
 
     @property
     def bracket_start(self):
         """
-        The indent of the bracket that is responsible for the last function
-        call.
+        The line/column of the bracket that is responsible for the last
+        function call.
         """
         return self._call_details.bracket_leaf.start_pos
 
-    @property
-    def _params_str(self):
-        return ', '.join([p.description[6:]
-                          for p in self.params])
-
     def __repr__(self):
-        return '<%s: %s index=%r params=[%s]>' % (
+        return '<%s: index=%r %s>' % (
             type(self).__name__,
-            self._name.string_name,
             self.index,
-            self._params_str,
+            self._signature.to_string(),
         )
 
 
+class ParamDefinition(Definition):
+    def infer_default(self):
+        """
+        :return list of Definition:
+        """
+        return _contexts_to_definitions(self._name.infer_default())
+
+    def infer_annotation(self, **kwargs):
+        """
+        :return list of Definition:
+
+        :param execute_annotation: If False, the values are not executed and
+            you get classes instead of instances.
+        """
+        return _contexts_to_definitions(self._name.infer_annotation(**kwargs))
+
+    def to_string(self):
+        return self._name.to_string()
+
+    @property
+    def kind(self):
+        """
+        Returns an enum instance. Returns the same values as the builtin
+        :py:attr:`inspect.Parameter.kind`.
+
+        No support for Python < 3.4 anymore.
+        """
+        if sys.version_info < (3, 5):
+            raise NotImplementedError(
+                'Python 2 is end-of-life, the new feature is not available for it'
+            )
+        return self._name.get_kind()
+
+
 def _format_signatures(context):
     return '\n'.join(
         signature.to_string()

jedi/api/completion.py

@@ -1,3 +1,5 @@
+import re
+
 from parso.python.token import PythonTokenTypes
 from parso.python import tree
 from parso.tree import search_ancestor, Leaf
@@ -7,12 +9,13 @@ from jedi import debug
 from jedi import settings
 from jedi.api import classes
 from jedi.api import helpers
-from jedi.evaluate import imports
 from jedi.api import keywords
+from jedi.api.file_name import file_name_completions
+from jedi.evaluate import imports
 from jedi.evaluate.helpers import evaluate_call_of_leaf, parse_dotted_names
 from jedi.evaluate.filters import get_global_filters
 from jedi.evaluate.gradual.conversion import convert_contexts
-from jedi.parser_utils import get_statement_of_position
+from jedi.parser_utils import get_statement_of_position, cut_value_at_position
 
 
 def get_call_signature_param_names(call_signatures):
@@ -82,7 +85,7 @@ def get_flow_scope_node(module_node, position):
 
 
 class Completion:
-    def __init__(self, evaluator, module, code_lines, position, call_signatures_method):
+    def __init__(self, evaluator, module, code_lines, position, call_signatures_callback):
         self._evaluator = evaluator
         self._module_context = module
         self._module_node = module.tree_node
@@ -92,11 +95,23 @@ class Completion:
         self._like_name = helpers.get_on_completion_name(self._module_node, code_lines, position)
         # The actual cursor position is not what we need to calculate
         # everything. We want the start of the name we're on.
+        self._original_position = position
         self._position = position[0], position[1] - len(self._like_name)
-        self._call_signatures_method = call_signatures_method
+        self._call_signatures_callback = call_signatures_callback
 
     def completions(self):
-        completion_names = self._get_context_completions()
+        leaf = self._module_node.get_leaf_for_position(self._position, include_prefixes=True)
+        string, start_leaf = _extract_string_while_in_string(leaf, self._position)
+        if string is not None:
+            completions = list(file_name_completions(
+                self._evaluator, self._module_context, start_leaf, string,
+                self._like_name, self._call_signatures_callback,
+                self._code_lines, self._original_position
+            ))
+            if completions:
+                return completions
+
+        completion_names = self._get_context_completions(leaf)
 
         completions = filter_names(self._evaluator, completion_names,
                                    self.stack, self._like_name)
@@ -105,7 +120,7 @@ class Completion:
                                                   x.name.startswith('_'),
                                                   x.name.lower()))
 
-    def _get_context_completions(self):
+    def _get_context_completions(self, leaf):
         """
         Analyzes the context that a completion is made in and decides what to
         return.
@@ -121,19 +136,20 @@ class Completion:
         """
 
         grammar = self._evaluator.grammar
+        self.stack = stack = None
 
         try:
             self.stack = stack = helpers.get_stack_at_position(
-                grammar, self._code_lines, self._module_node, self._position
+                grammar, self._code_lines, leaf, self._position
             )
         except helpers.OnErrorLeaf as e:
-            self.stack = stack = None
-            if e.error_leaf.value == '.':
+            value = e.error_leaf.value
+            if value == '.':
                 # After ErrorLeaf's that are dots, we will not do any
                 # completions since this probably just confuses the user.
                 return []
-            # If we don't have a context, just use global completion.
 
+            # If we don't have a context, just use global completion.
             return self._global_completions()
 
         allowed_transitions = \
@@ -210,7 +226,7 @@ class Completion:
                 completion_names += self._get_class_context_completions(is_function=False)
 
             if 'trailer' in nonterminals:
-                call_signatures = self._call_signatures_method()
+                call_signatures = self._call_signatures_callback()
                 completion_names += get_call_signature_param_names(call_signatures)
 
         return completion_names
@@ -289,3 +305,22 @@ class Completion:
                 # TODO we should probably check here for properties
                 if (name.api_type == 'function') == is_function:
                     yield name
+
+
+def _extract_string_while_in_string(leaf, position):
+    if leaf.type == 'string':
+        match = re.match(r'^\w*(\'{3}|"{3}|\'|")', leaf.value)
+        quote = match.group(1)
+        if leaf.line == position[0] and position[1] < leaf.column + match.end():
+            return None, None
+        if leaf.end_pos[0] == position[0] and position[1] > leaf.end_pos[1] - len(quote):
+            return None, None
+        return cut_value_at_position(leaf, position)[match.end():], leaf
+
+    leaves = []
+    while leaf is not None and leaf.line == position[0]:
+        if leaf.type == 'error_leaf' and ('"' in leaf.value or "'" in leaf.value):
+            return ''.join(l.get_code() for l in leaves), leaf
+        leaves.insert(0, leaf)
+        leaf = leaf.get_previous_leaf()
+    return None, None

jedi/api/file_name.py

@@ -0,0 +1,161 @@
+import os
+
+from jedi._compatibility import FileNotFoundError, force_unicode
+from jedi.evaluate.names import AbstractArbitraryName
+from jedi.api import classes
+from jedi.evaluate.helpers import get_str_or_none
+from jedi.parser_utils import get_string_quote
+
+
+def file_name_completions(evaluator, module_context, start_leaf, string,
+                          like_name, call_signatures_callback, code_lines, position):
+    # First we want to find out what can actually be changed as a name.
+    like_name_length = len(os.path.basename(string) + like_name)
+
+    addition = _get_string_additions(module_context, start_leaf)
+    if addition is None:
+        return
+    string = addition + string
+
+    # Here we use basename again, because if strings are added like
+    # `'foo' + 'bar`, it should complete to `foobar/`.
+    must_start_with = os.path.basename(string) + like_name
+    string = os.path.dirname(string)
+
+    sigs = call_signatures_callback()
+    is_in_os_path_join = sigs and all(s.full_name == 'os.path.join' for s in sigs)
+    if is_in_os_path_join:
+        to_be_added = _add_os_path_join(module_context, start_leaf, sigs[0].bracket_start)
+        if to_be_added is None:
+            is_in_os_path_join = False
+        else:
+            string = to_be_added + string
+    base_path = os.path.join(evaluator.project._path, string)
+    try:
+        listed = os.listdir(base_path)
+    except FileNotFoundError:
+        return
+    for name in listed:
+        if name.startswith(must_start_with):
+            path_for_name = os.path.join(base_path, name)
+            if is_in_os_path_join or not os.path.isdir(path_for_name):
+                if start_leaf.type == 'string':
+                    quote = get_string_quote(start_leaf)
+                else:
+                    assert start_leaf.type == 'error_leaf'
+                    quote = start_leaf.value
+                potential_other_quote = \
+                    code_lines[position[0] - 1][position[1]:position[1] + len(quote)]
+                # Add a quote if it's not already there.
+                if quote != potential_other_quote:
+                    name += quote
+            else:
+                name += os.path.sep
+
+            yield classes.Completion(
+                evaluator,
+                FileName(evaluator, name[len(must_start_with) - like_name_length:]),
+                stack=None,
+                like_name_length=like_name_length
+            )
+
+
+def _get_string_additions(module_context, start_leaf):
+    def iterate_nodes():
+        node = addition.parent
+        was_addition = True
+        for child_node in reversed(node.children[:node.children.index(addition)]):
+            if was_addition:
+                was_addition = False
+                yield child_node
+                continue
+
+            if child_node != '+':
+                break
+            was_addition = True
+
+    addition = start_leaf.get_previous_leaf()
+    if addition != '+':
+        return ''
+    context = module_context.create_context(start_leaf)
+    return _add_strings(context, reversed(list(iterate_nodes())))
+
+
+def _add_strings(context, nodes, add_slash=False):
+    string = ''
+    first = True
+    for child_node in nodes:
+        contexts = context.eval_node(child_node)
+        if len(contexts) != 1:
+            return None
+        c, = contexts
+        s = get_str_or_none(c)
+        if s is None:
+            return None
+        if not first and add_slash:
+            string += os.path.sep
+        string += force_unicode(s)
+        first = False
+    return string
+
+
+class FileName(AbstractArbitraryName):
+    api_type = u'path'
+    is_context_name = False
+
+
+def _add_os_path_join(module_context, start_leaf, bracket_start):
+    def check(maybe_bracket, nodes):
+        if maybe_bracket.start_pos != bracket_start:
+            return None
+
+        if not nodes:
+            return ''
+        context = module_context.create_context(nodes[0])
+        return _add_strings(context, nodes, add_slash=True) or ''
+
+    if start_leaf.type == 'error_leaf':
+        # Unfinished string literal, like `join('`
+        context_node = start_leaf.parent
+        index = context_node.children.index(start_leaf)
+        if index > 0:
+            error_node = context_node.children[index - 1]
+            if error_node.type == 'error_node' and len(error_node.children) >= 2:
+                index = -2
+                if error_node.children[-1].type == 'arglist':
+                    arglist_nodes = error_node.children[-1].children
+                    index -= 1
+                else:
+                    arglist_nodes = []
+
+                return check(error_node.children[index + 1], arglist_nodes[::2])
+        return None
+
+    # Maybe an arglist or some weird error case. Therefore checked below.
+    searched_node_child = start_leaf
+    while searched_node_child.parent is not None \
+            and searched_node_child.parent.type not in ('arglist', 'trailer', 'error_node'):
+        searched_node_child = searched_node_child.parent
+
+    if searched_node_child.get_first_leaf() is not start_leaf:
+        return None
+    searched_node = searched_node_child.parent
+    if searched_node is None:
+        return None
+
+    index = searched_node.children.index(searched_node_child)
+    arglist_nodes = searched_node.children[:index]
+    if searched_node.type == 'arglist':
+        trailer = searched_node.parent
+        if trailer.type == 'error_node':
+            trailer_index = trailer.children.index(searched_node)
+            assert trailer_index >= 2
+            assert trailer.children[trailer_index - 1] == '('
+            return check(trailer.children[trailer_index - 1], arglist_nodes[::2])
+        elif trailer.type == 'trailer':
+            return check(trailer.children[0], arglist_nodes[::2])
+    elif searched_node.type == 'trailer':
+        return check(searched_node.children[0], [])
+    elif searched_node.type == 'error_node':
+        # Stuff like `join(""`
+        return check(arglist_nodes[-1], [])

jedi/api/helpers.py

@@ -54,8 +54,7 @@ class OnErrorLeaf(Exception):
         return self.args[0]
 
 
-def _get_code_for_stack(code_lines, module_node, position):
-    leaf = module_node.get_leaf_for_position(position, include_prefixes=True)
+def _get_code_for_stack(code_lines, leaf, position):
     # It might happen that we're on whitespace or on a comment. This means
     # that we would not get the right leaf.
     if leaf.start_pos >= position:
@@ -95,7 +94,7 @@ def _get_code_for_stack(code_lines, module_node, position):
         return _get_code(code_lines, user_stmt.get_start_pos_of_prefix(), position)
 
 
-def get_stack_at_position(grammar, code_lines, module_node, pos):
+def get_stack_at_position(grammar, code_lines, leaf, pos):
     """
     Returns the possible node names (e.g. import_from, xor_test or yield_stmt).
     """
@@ -119,7 +118,7 @@ def get_stack_at_position(grammar, code_lines, module_node, pos):
                 yield token
 
     # The code might be indedented, just remove it.
-    code = dedent(_get_code_for_stack(code_lines, module_node, pos))
+    code = dedent(_get_code_for_stack(code_lines, leaf, pos))
     # We use a word to tell Jedi when we have reached the start of the
     # completion.
     # Use Z as a prefix because it's not part of a number suffix.

jedi/api/keywords.py

@@ -1,7 +1,7 @@
 import pydoc
 
 from jedi.evaluate.utils import ignored
-from jedi.evaluate.names import AbstractNameDefinition
+from jedi.evaluate.names import AbstractArbitraryName
 
 try:
     from pydoc_data import topics as pydoc_topics
@@ -19,14 +19,8 @@ def get_operator(evaluator, string, pos):
     return Keyword(evaluator, string, pos)
 
 
-class KeywordName(AbstractNameDefinition):
+class KeywordName(AbstractArbitraryName):
     api_type = u'keyword'
-    is_context_name = False
-
-    def __init__(self, evaluator, name):
-        self.evaluator = evaluator
-        self.string_name = name
-        self.parent_context = evaluator.builtins_module
 
     def infer(self):
         return [Keyword(self.evaluator, self.string_name, (0, 0))]

jedi/evaluate/__init__.py

@@ -62,8 +62,6 @@ I need to mention now that lazy evaluation is really good because it
 only *evaluates* what needs to be *evaluated*. All the statements and modules
 that are not used are just being ignored.
 """
-from functools import partial
-
 from parso.python import tree
 import parso
 from parso import python_bytes_to_unicode
@@ -84,14 +82,7 @@ from jedi.evaluate.context import ClassContext, FunctionContext, \
 from jedi.evaluate.context.iterable import CompForContext
 from jedi.evaluate.syntax_tree import eval_trailer, eval_expr_stmt, \
     eval_node, check_tuple_assignments
-
-
-def _execute(context, arguments):
-    debug.dbg('execute: %s %s', context, arguments)
-    with debug.increase_indent_cm():
-        context_set = context.py__call__(arguments=arguments)
-    debug.dbg('execute result: %s in %s', context_set, context)
-    return context_set
+from jedi.plugins import plugin_manager
 
 
 class Evaluator(object):
@@ -115,28 +106,26 @@ class Evaluator(object):
         self.is_analysis = False
         self.project = project
         self.access_cache = {}
+        self.allow_descriptor_getattr = False
 
         self.reset_recursion_limitations()
         self.allow_different_encoding = True
 
-        # Plugin API
-        from jedi.plugins import plugin_manager
-        plugin_callbacks = plugin_manager.get_callbacks(self)
-        self.execute = plugin_callbacks.decorate('execute', callback=_execute)
-        self._import_module = partial(
-            plugin_callbacks.decorate(
-                'import_module',
-                callback=imports.import_module
-            ),
-            self,
-        )
-
     def import_module(self, import_names, parent_module_context=None,
                       sys_path=None, prefer_stubs=True):
         if sys_path is None:
             sys_path = self.get_sys_path()
-        return self._import_module(import_names, parent_module_context,
-                                   sys_path, prefer_stubs=prefer_stubs)
+        return imports.import_module(self, import_names, parent_module_context,
+                                     sys_path, prefer_stubs=prefer_stubs)
+
+    @staticmethod
+    @plugin_manager.decorate()
+    def execute(context, arguments):
+        debug.dbg('execute: %s %s', context, arguments)
+        with debug.increase_indent_cm():
+            context_set = context.py__call__(arguments=arguments)
+        debug.dbg('execute result: %s in %s', context_set, context)
+        return context_set
 
     @property
     @evaluator_function_cache()

jedi/evaluate/arguments.py

@@ -11,6 +11,7 @@ from jedi.evaluate.lazy_context import LazyKnownContext, LazyKnownContexts, \
 from jedi.evaluate.names import ParamName, TreeNameDefinition
 from jedi.evaluate.base_context import NO_CONTEXTS, ContextSet, ContextualizedNode
 from jedi.evaluate.context import iterable
+from jedi.evaluate.cache import evaluator_as_method_param_cache
 from jedi.evaluate.param import get_executed_params_and_issues, ExecutedParam
 
 
@@ -35,7 +36,7 @@ class ParamIssue(Exception):
     pass
 
 
-def repack_with_argument_clinic(string, keep_arguments_param=False):
+def repack_with_argument_clinic(string, keep_arguments_param=False, keep_callback_param=False):
     """
     Transforms a function or method with arguments to the signature that is
     given as an argument clinic notation.
@@ -54,6 +55,8 @@ def repack_with_argument_clinic(string, keep_arguments_param=False):
                 arguments = kwargs['arguments']
             else:
                 arguments = kwargs.pop('arguments')
+            if not keep_arguments_param:
+                kwargs.pop('callback', None)
             try:
                 args += tuple(_iterate_argument_clinic(
                     context.evaluator,
@@ -208,6 +211,11 @@ class TreeArguments(AbstractArguments):
         self._evaluator = evaluator
         self.trailer = trailer  # Can be None, e.g. in a class definition.
 
+    @classmethod
+    @evaluator_as_method_param_cache()
+    def create_cached(cls, *args, **kwargs):
+        return cls(*args, **kwargs)
+
     def unpack(self, funcdef=None):
         named_args = []
         for star_count, el in unpack_arglist(self.argument_node):

jedi/evaluate/compiled/__init__.py

@@ -1,7 +1,7 @@
 from jedi._compatibility import unicode
 from jedi.evaluate.compiled.context import CompiledObject, CompiledName, \
     CompiledObjectFilter, CompiledContextName, create_from_access_path
-from jedi.evaluate.base_context import ContextWrapper
+from jedi.evaluate.base_context import ContextWrapper, LazyContextWrapper
 
 
 def builtin_from_name(evaluator, string):
@@ -16,9 +16,9 @@ def builtin_from_name(evaluator, string):
     return context
 
 
-class CompiledValue(ContextWrapper):
-    def __init__(self, instance, compiled_obj):
-        super(CompiledValue, self).__init__(instance)
+class CompiledValue(LazyContextWrapper):
+    def __init__(self, compiled_obj):
+        self.evaluator = compiled_obj.evaluator
         self._compiled_obj = compiled_obj
 
     def __getattribute__(self, name):
@@ -27,6 +27,11 @@ class CompiledValue(ContextWrapper):
             return getattr(self._compiled_obj, name)
         return super(CompiledValue, self).__getattribute__(name)
 
+    def _get_wrapped_context(self):
+        instance, = builtin_from_name(
+            self.evaluator, self._compiled_obj.name.string_name).execute_evaluated()
+        return instance
+
     def __repr__(self):
         return '<%s: %s>' % (self.__class__.__name__, self._compiled_obj)
 
@@ -41,8 +46,7 @@ def create_simple_object(evaluator, obj):
         evaluator,
         evaluator.compiled_subprocess.create_simple_object(obj)
     )
-    instance, = builtin_from_name(evaluator, compiled_obj.name.string_name).execute_evaluated()
-    return CompiledValue(instance, compiled_obj)
+    return CompiledValue(compiled_obj)
 
 
 def get_string_context_set(evaluator):

jedi/evaluate/compiled/access.py

@@ -84,9 +84,14 @@ def safe_getattr(obj, name, default=_sentinel):
             raise
         return default
     else:
-        if type(attr) in ALLOWED_DESCRIPTOR_ACCESS:
+        if isinstance(attr, ALLOWED_DESCRIPTOR_ACCESS):
             # In case of descriptors that have get methods we cannot return
             # it's value, because that would mean code execution.
+            # Since it's an isinstance call, code execution is still possible,
+            # but this is not really a security feature, but much more of a
+            # safety feature. Code execution is basically always possible when
+            # a module is imported. This is here so people don't shoot
+            # themselves in the foot.
             return getattr(obj, name)
     return attr
 
@@ -175,6 +180,18 @@ def _force_unicode_decorator(func):
     return lambda *args, **kwargs: force_unicode(func(*args, **kwargs))
 
 
+def get_api_type(obj):
+    if inspect.isclass(obj):
+        return u'class'
+    elif inspect.ismodule(obj):
+        return u'module'
+    elif inspect.isbuiltin(obj) or inspect.ismethod(obj) \
+            or inspect.ismethoddescriptor(obj) or inspect.isfunction(obj):
+        return u'function'
+    # Everything else...
+    return u'instance'
+
+
 class DirectObjectAccess(object):
     def __init__(self, evaluator, obj):
         self._evaluator = evaluator
@@ -328,12 +345,16 @@ class DirectObjectAccess(object):
     def getattr_paths(self, name, default=_sentinel):
         try:
             return_obj = getattr(self._obj, name)
-        except AttributeError:
-            # Happens e.g. in properties of
-            # PyQt4.QtGui.QStyleOptionComboBox.currentText
-            # -> just set it to None
+        except Exception as e:
             if default is _sentinel:
-                raise
+                if isinstance(e, AttributeError):
+                    # Happens e.g. in properties of
+                    # PyQt4.QtGui.QStyleOptionComboBox.currentText
+                    # -> just set it to None
+                    raise
+                # Just in case anything happens, return an AttributeError. It
+                # should not crash.
+                raise AttributeError
             return_obj = default
         access = self._create_access(return_obj)
         if inspect.ismodule(return_obj):
@@ -352,16 +373,7 @@ class DirectObjectAccess(object):
         raise ValueError("Object is type %s and not simple" % type(self._obj))
 
     def get_api_type(self):
-        obj = self._obj
-        if self.is_class():
-            return u'class'
-        elif inspect.ismodule(obj):
-            return u'module'
-        elif inspect.isbuiltin(obj) or inspect.ismethod(obj) \
-                or inspect.ismethoddescriptor(obj) or inspect.isfunction(obj):
-            return u'function'
-        # Everything else...
-        return u'instance'
+        return get_api_type(self._obj)
 
     def get_access_path_tuples(self):
         accesses = [create_access(self._evaluator, o) for o in self._get_objects_path()]

jedi/evaluate/compiled/context.py

@@ -264,6 +264,9 @@ class CompiledObject(Context):
     def negate(self):
         return create_from_access_path(self.evaluator, self.access_handle.negate())
 
+    def get_metaclasses(self):
+        return NO_CONTEXTS
+
 
 class CompiledName(AbstractNameDefinition):
     def __init__(self, evaluator, parent_context, name):
@@ -317,9 +320,6 @@ class SignatureParamName(ParamNameInterface, AbstractNameDefinition):
     def get_kind(self):
         return getattr(Parameter, self._signature_param.kind_name)
 
-    def is_keyword_param(self):
-        return self._signature_param
-
     def infer(self):
         p = self._signature_param
         evaluator = self.parent_context.evaluator
@@ -377,14 +377,14 @@ class CompiledObjectFilter(AbstractFilter):
 
     def __init__(self, evaluator, compiled_object, is_instance=False):
         self._evaluator = evaluator
-        self._compiled_object = compiled_object
+        self.compiled_object = compiled_object
         self.is_instance = is_instance
 
     def get(self, name):
         return self._get(
             name,
-            lambda: self._compiled_object.access_handle.is_allowed_getattr(name),
-            lambda: self._compiled_object.access_handle.dir(),
+            lambda: self.compiled_object.access_handle.is_allowed_getattr(name),
+            lambda: self.compiled_object.access_handle.dir(),
             check_has_attribute=True
         )
 
@@ -399,7 +399,7 @@ class CompiledObjectFilter(AbstractFilter):
         # Always use unicode objects in Python 2 from here.
         name = force_unicode(name)
 
-        if is_descriptor or not has_attribute:
+        if (is_descriptor and not self._evaluator.allow_descriptor_getattr) or not has_attribute:
             return [self._get_cached_name(name, is_empty=True)]
 
         if self.is_instance and name not in dir_callback():
@@ -416,7 +416,7 @@ class CompiledObjectFilter(AbstractFilter):
     def values(self):
         from jedi.evaluate.compiled import builtin_from_name
         names = []
-        needs_type_completions, dir_infos = self._compiled_object.access_handle.get_dir_infos()
+        needs_type_completions, dir_infos = self.compiled_object.access_handle.get_dir_infos()
         for name in dir_infos:
             names += self._get(
                 name,
@@ -431,10 +431,10 @@ class CompiledObjectFilter(AbstractFilter):
         return names
 
     def _create_name(self, name):
-        return self.name_class(self._evaluator, self._compiled_object, name)
+        return self.name_class(self._evaluator, self.compiled_object, name)
 
     def __repr__(self):
-        return "<%s: %s>" % (self.__class__.__name__, self._compiled_object)
+        return "<%s: %s>" % (self.__class__.__name__, self.compiled_object)
 
 
 docstr_defaults = {

jedi/evaluate/compiled/mixed.py

@@ -18,7 +18,7 @@ from jedi.evaluate.context import ModuleContext
 from jedi.evaluate.cache import evaluator_function_cache
 from jedi.evaluate.compiled.getattr_static import getattr_static
 from jedi.evaluate.compiled.access import compiled_objects_cache, \
-    ALLOWED_GETITEM_TYPES
+    ALLOWED_GETITEM_TYPES, get_api_type
 from jedi.evaluate.compiled.context import create_cached_compiled_object
 from jedi.evaluate.gradual.conversion import to_stub
 
@@ -50,6 +50,11 @@ class MixedObject(ContextWrapper):
     def get_filters(self, *args, **kwargs):
         yield MixedObjectFilter(self.evaluator, self)
 
+    def get_signatures(self):
+        # Prefer `inspect.signature` over somehow analyzing Python code. It
+        # should be very precise, especially for stuff like `partial`.
+        return self.compiled_object.get_signatures()
+
     def py__call__(self, arguments):
         return (to_stub(self._wrapped_context) or self._wrapped_context).py__call__(arguments)
 
@@ -151,6 +156,7 @@ def _get_object_to_check(python_object):
 
 
 def _find_syntax_node_name(evaluator, python_object):
+    original_object = python_object
     try:
         python_object = _get_object_to_check(python_object)
         path = inspect.getsourcefile(python_object)
@@ -214,7 +220,13 @@ def _find_syntax_node_name(evaluator, python_object):
     # completions at some points but will lead to mostly correct type
     # inference, because people tend to define a public name in a module only
     # once.
-    return module_node, names[-1].parent, file_io, code_lines
+    tree_node = names[-1].parent
+    if tree_node.type == 'funcdef' and get_api_type(original_object) == 'instance':
+        # If an instance is given and we're landing on a function (e.g.
+        # partial in 3.5), something is completely wrong and we should not
+        # return that.
+        return None
+    return module_node, tree_node, file_io, code_lines
 
 
 @compiled_objects_cache('mixed_cache')
@@ -254,7 +266,11 @@ def _create(evaluator, access_handle, parent_context, *args):
             if name is not None:
                 evaluator.module_cache.add(string_names, ContextSet([module_context]))
         else:
-            assert parent_context.tree_node.get_root_node() == module_node
+            if parent_context.tree_node.get_root_node() != module_node:
+                # This happens e.g. when __module__ is wrong, or when using
+                # TypeVar('foo'), where Jedi uses 'foo' as the name and
+                # Python's TypeVar('foo').__module__ will be typing.
+                return ContextSet({compiled_object})
             module_context = parent_context.get_root_context()
 
         tree_contexts = ContextSet({

jedi/evaluate/context/decorator.py

@@ -0,0 +1,15 @@
+'''
+Decorators are not really contexts, however we need some wrappers to improve
+docstrings and other things around decorators.
+'''
+
+from jedi.evaluate.base_context import ContextWrapper
+
+
+class Decoratee(ContextWrapper):
+    def __init__(self, wrapped_context, original_context):
+        self._wrapped_context = wrapped_context
+        self._original_context = original_context
+
+    def py__doc__(self):
+        return self._original_context.py__doc__()

jedi/evaluate/context/function.py

@@ -100,6 +100,9 @@ class FunctionMixin(object):
 
         return FunctionExecutionContext(self.evaluator, self.parent_context, self, arguments)
 
+    def get_signatures(self):
+        return [TreeSignature(f) for f in self.get_signature_functions()]
+
 
 class FunctionContext(use_metaclass(CachedMetaClass, FunctionMixin, FunctionAndClassBase)):
     """
@@ -147,8 +150,8 @@ class FunctionContext(use_metaclass(CachedMetaClass, FunctionMixin, FunctionAndC
     def get_default_param_context(self):
         return self.parent_context
 
-    def get_signatures(self):
-        return [TreeSignature(self)]
+    def get_signature_functions(self):
+        return [self]
 
 
 class MethodContext(FunctionContext):
@@ -371,14 +374,14 @@ class FunctionExecutionContext(TreeContext):
 class OverloadedFunctionContext(FunctionMixin, ContextWrapper):
     def __init__(self, function, overloaded_functions):
         super(OverloadedFunctionContext, self).__init__(function)
-        self.overloaded_functions = overloaded_functions
+        self._overloaded_functions = overloaded_functions
 
     def py__call__(self, arguments):
         debug.dbg("Execute overloaded function %s", self._wrapped_context, color='BLUE')
         function_executions = []
         context_set = NO_CONTEXTS
         matched = False
-        for f in self.overloaded_functions:
+        for f in self._overloaded_functions:
             function_execution = f.get_function_execution(arguments)
             function_executions.append(function_execution)
             if function_execution.matches_signature():
@@ -393,39 +396,8 @@ class OverloadedFunctionContext(FunctionMixin, ContextWrapper):
             return NO_CONTEXTS
         return ContextSet.from_sets(fe.infer() for fe in function_executions)
 
-    def get_signatures(self):
-        return [TreeSignature(f) for f in self.overloaded_functions]
-
-
-def signature_matches(function_context, arguments):
-    unpacked_arguments = arguments.unpack()
-    key_args = {}
-    for param_node in function_context.tree_node.get_params():
-        while True:
-            key, argument = next(unpacked_arguments, (None, None))
-            if key is None or argument is None:
-                break
-            key_args[key] = argument
-        if argument is None:
-            argument = key_args.pop(param_node.name.value, None)
-            if argument is None:
-                # This signature has an parameter more than arguments were given.
-                return bool(param_node.star_count == 1)
-
-        if param_node.annotation is not None:
-            if param_node.star_count == 2:
-                return False  # TODO allow this
-
-            annotation_contexts = function_context.evaluator.eval_element(
-                function_context.get_default_param_context(),
-                param_node.annotation
-            )
-            argument_contexts = argument.infer().py__class__()
-            if not any(c1.is_sub_class_of(c2)
-                       for c1 in argument_contexts
-                       for c2 in annotation_contexts):
-                return False
-    return True
+    def get_signature_functions(self):
+        return self._overloaded_functions
 
 
 def _find_overload_functions(context, tree_node):

jedi/evaluate/context/instance.py

@@ -3,6 +3,7 @@ from abc import abstractproperty
 from jedi import debug
 from jedi import settings
 from jedi.evaluate import compiled
+from jedi.evaluate.compiled.context import CompiledObjectFilter
 from jedi.evaluate.helpers import contexts_from_qualified_names
 from jedi.evaluate.filters import AbstractFilter
 from jedi.evaluate.names import ContextName, TreeNameDefinition
@@ -12,7 +13,7 @@ from jedi.evaluate.lazy_context import LazyKnownContext, LazyKnownContexts
 from jedi.evaluate.cache import evaluator_method_cache
 from jedi.evaluate.arguments import AnonymousArguments, \
     ValuesArguments, TreeArgumentsWrapper
-from jedi.evaluate.context.function import FunctionExecutionContext, \
+from jedi.evaluate.context.function import \
     FunctionContext, FunctionMixin, OverloadedFunctionContext
 from jedi.evaluate.context.klass import ClassContext, apply_py__get__, \
     ClassFilter
@@ -136,11 +137,19 @@ class AbstractInstanceContext(Context):
                     # compiled objects to search for self variables.
                     yield SelfAttributeFilter(self.evaluator, self, cls, origin_scope)
 
-        for cls in class_context.py__mro__():
-            if isinstance(cls, compiled.CompiledObject):
-                yield CompiledInstanceClassFilter(self.evaluator, self, cls)
+        class_filters = class_context.get_filters(
+            search_global=False,
+            origin_scope=origin_scope,
+            is_instance=True,
+        )
+        for f in class_filters:
+            if isinstance(f, ClassFilter):
+                yield InstanceClassFilter(self.evaluator, self, f)
+            elif isinstance(f, CompiledObjectFilter):
+                yield CompiledInstanceClassFilter(self.evaluator, self, f)
             else:
-                yield InstanceClassFilter(self.evaluator, self, cls, origin_scope)
+                # Propably from the metaclass.
+                yield f
 
     def py__getitem__(self, index_context_set, contextualized_node):
         names = self.get_function_slot_names(u'__getitem__')
@@ -223,8 +232,8 @@ class AbstractInstanceContext(Context):
         return class_context
 
     def get_signatures(self):
-        init_funcs = self.py__getattribute__('__call__')
-        return [sig.bind(self) for sig in init_funcs.get_signatures()]
+        call_funcs = self.py__getattribute__('__call__').py__get__(self, self.class_context)
+        return [s.bind(self) for s in call_funcs.get_signatures()]
 
     def __repr__(self):
         return "<%s of %s(%s)>" % (self.__class__.__name__, self.class_context,
@@ -328,7 +337,6 @@ class CompiledInstanceName(compiled.CompiledName):
             name.string_name
         )
         self._instance = instance
-        self._class = klass
         self._class_member_name = name
 
     @iterator_to_context_set
@@ -343,11 +351,10 @@ class CompiledInstanceName(compiled.CompiledName):
 class CompiledInstanceClassFilter(AbstractFilter):
     name_class = CompiledInstanceName
 
-    def __init__(self, evaluator, instance, klass):
+    def __init__(self, evaluator, instance, f):
         self._evaluator = evaluator
         self._instance = instance
-        self._class = klass
-        self._class_filter = next(klass.get_filters(is_instance=True))
+        self._class_filter = f
 
     def get(self, name):
         return self._convert(self._class_filter.get(name))
@@ -356,8 +363,9 @@ class CompiledInstanceClassFilter(AbstractFilter):
         return self._convert(self._class_filter.values())
 
     def _convert(self, names):
+        klass = self._class_filter.compiled_object
         return [
-            CompiledInstanceName(self._evaluator, self._instance, self._class, n)
+            CompiledInstanceName(self._evaluator, self._instance, klass, n)
             for n in names
         ]
 
@@ -382,15 +390,6 @@ class BoundMethod(FunctionMixin, ContextWrapper):
 
     def get_function_execution(self, arguments=None):
         arguments = self._get_arguments(arguments)
-
-        if isinstance(self._wrapped_context, compiled.CompiledObject):
-            # This is kind of weird, because it's coming from a compiled object
-            # and we're not sure if we want that in the future.
-            # TODO remove?!
-            return FunctionExecutionContext(
-                self.evaluator, self.parent_context, self, arguments
-            )
-
         return super(BoundMethod, self).get_function_execution(arguments)
 
     def py__call__(self, arguments):
@@ -400,8 +399,14 @@ class BoundMethod(FunctionMixin, ContextWrapper):
         function_execution = self.get_function_execution(arguments)
         return function_execution.infer()
 
+    def get_signature_functions(self):
+        return [
+            BoundMethod(self.instance, f)
+            for f in self._wrapped_context.get_signature_functions()
+        ]
+
     def get_signatures(self):
-        return [sig.bind(self) for sig in self._wrapped_context.get_signatures()]
+        return [sig.bind(self) for sig in super(BoundMethod, self).get_signatures()]
 
     def __repr__(self):
         return '<%s: %s>' % (self.__class__.__name__, self._wrapped_context)
@@ -454,15 +459,9 @@ class InstanceClassFilter(AbstractFilter):
     resulting names in LazyINstanceClassName. The idea is that the class name
     filtering can be very flexible and always be reflected in instances.
     """
-    def __init__(self, evaluator, context, class_context, origin_scope):
-        self._instance = context
-        self._class_context = class_context
-        self._class_filter = next(class_context.get_filters(
-            search_global=False,
-            origin_scope=origin_scope,
-            is_instance=True,
-        ))
-        assert isinstance(self._class_filter, ClassFilter), self._class_filter
+    def __init__(self, evaluator, instance, class_filter):
+        self._instance = instance
+        self._class_filter = class_filter
 
     def get(self, name):
         return self._convert(self._class_filter.get(name, from_instance=True))
@@ -471,10 +470,10 @@ class InstanceClassFilter(AbstractFilter):
         return self._convert(self._class_filter.values(from_instance=True))
 
     def _convert(self, names):
-        return [LazyInstanceClassName(self._instance, self._class_context, n) for n in names]
+        return [LazyInstanceClassName(self._instance, self._class_filter.context, n) for n in names]
 
     def __repr__(self):
-        return '<%s for %s>' % (self.__class__.__name__, self._class_context)
+        return '<%s for %s>' % (self.__class__.__name__, self._class_filter.context)
 
 
 class SelfAttributeFilter(ClassFilter):

jedi/evaluate/context/iterable.py

@@ -20,6 +20,8 @@ It is important to note that:
 1. Array modfications work only in the current module.
 2. Jedi only checks Array additions; ``list.pop``, etc are ignored.
 """
+import sys
+
 from jedi import debug
 from jedi import settings
 from jedi._compatibility import force_unicode, is_py3
@@ -35,8 +37,8 @@ from jedi.evaluate.utils import safe_property, to_list
 from jedi.evaluate.cache import evaluator_method_cache
 from jedi.evaluate.filters import ParserTreeFilter, LazyAttributeOverwrite, \
     publish_method
-from jedi.evaluate.base_context import ContextSet, NO_CONTEXTS, \
-    TreeContext, ContextualizedNode, iterate_contexts, HelperContextMixin
+from jedi.evaluate.base_context import ContextSet, Context, NO_CONTEXTS, \
+    TreeContext, ContextualizedNode, iterate_contexts, HelperContextMixin, _sentinel
 from jedi.parser_utils import get_sync_comp_fors
 
 
@@ -44,6 +46,21 @@ class IterableMixin(object):
     def py__stop_iteration_returns(self):
         return ContextSet([compiled.builtin_from_name(self.evaluator, u'None')])
 
+    # At the moment, safe values are simple values like "foo", 1 and not
+    # lists/dicts. Therefore as a small speed optimization we can just do the
+    # default instead of resolving the lazy wrapped contexts, that are just
+    # doing this in the end as well.
+    # This mostly speeds up patterns like `sys.version_info >= (3, 0)` in
+    # typeshed.
+    if sys.version_info[0] == 2:
+        # Python 2...........
+        def get_safe_value(self, default=_sentinel):
+            if default is _sentinel:
+                raise ValueError("There exists no safe value for context %s" % self)
+            return default
+    else:
+        get_safe_value = Context.get_safe_value
+
 
 class GeneratorBase(LazyAttributeOverwrite, IterableMixin):
     array_type = None

jedi/evaluate/context/klass.py

@@ -49,6 +49,7 @@ from jedi.evaluate.arguments import unpack_arglist, ValuesArguments
 from jedi.evaluate.base_context import ContextSet, iterator_to_context_set, \
     NO_CONTEXTS
 from jedi.evaluate.context.function import FunctionAndClassBase
+from jedi.plugins import plugin_manager
 
 
 def apply_py__get__(context, instance, class_context):
@@ -136,8 +137,10 @@ class ClassMixin(object):
     def is_class(self):
         return True
 
-    def py__call__(self, arguments):
+    def py__call__(self, arguments=None):
         from jedi.evaluate.context import TreeInstance
+        if arguments is None:
+            arguments = ValuesArguments([])
         return ContextSet([TreeInstance(self.evaluator, self.parent_context, self, arguments)])
 
     def py__class__(self):
@@ -191,13 +194,13 @@ class ClassMixin(object):
 
     def get_filters(self, search_global=False, until_position=None,
                     origin_scope=None, is_instance=False):
+        metaclasses = self.get_metaclasses()
+        if metaclasses:
+            for f in self.get_metaclass_filters(metaclasses):
+                yield f
+
         if search_global:
-            yield ParserTreeFilter(
-                self.evaluator,
-                context=self,
-                until_position=until_position,
-                origin_scope=origin_scope
-            )
+            yield self.get_global_filter(until_position, origin_scope)
         else:
             for cls in self.py__mro__():
                 if isinstance(cls, compiled.CompiledObject):
@@ -214,13 +217,25 @@ class ClassMixin(object):
             type_ = builtin_from_name(self.evaluator, u'type')
             assert isinstance(type_, ClassContext)
             if type_ != self:
-                for instance in type_.py__call__(ValuesArguments([])):
+                for instance in type_.py__call__():
                     instance_filters = instance.get_filters()
                     # Filter out self filters
                     next(instance_filters)
                     next(instance_filters)
                     yield next(instance_filters)
 
+    def get_signatures(self):
+        init_funcs = self.py__call__().py__getattribute__('__init__')
+        return [sig.bind(self) for sig in init_funcs.get_signatures()]
+
+    def get_global_filter(self, until_position=None, origin_scope=None):
+        return ParserTreeFilter(
+            self.evaluator,
+            context=self,
+            until_position=until_position,
+            origin_scope=origin_scope
+        )
+
 
 class ClassContext(use_metaclass(CachedMetaClass, ClassMixin, FunctionAndClassBase)):
     """
@@ -247,12 +262,17 @@ class ClassContext(use_metaclass(CachedMetaClass, ClassMixin, FunctionAndClassBa
                     found.append(type_var)
         return found
 
-    @evaluator_method_cache(default=())
-    def py__bases__(self):
+    def _get_bases_arguments(self):
         arglist = self.tree_node.get_super_arglist()
         if arglist:
             from jedi.evaluate import arguments
-            args = arguments.TreeArguments(self.evaluator, self.parent_context, arglist)
+            return arguments.TreeArguments(self.evaluator, self.parent_context, arglist)
+        return None
+
+    @evaluator_method_cache(default=())
+    def py__bases__(self):
+        args = self._get_bases_arguments()
+        if args is not None:
             lst = [value for key, value in args.unpack() if key is None]
             if lst:
                 return lst
@@ -300,6 +320,25 @@ class ClassContext(use_metaclass(CachedMetaClass, ClassMixin, FunctionAndClassBa
             )])
         return ContextSet({self})
 
-    def get_signatures(self):
-        init_funcs = self.py__getattribute__('__init__')
-        return [sig.bind(self) for sig in init_funcs.get_signatures()]
+    @plugin_manager.decorate()
+    def get_metaclass_filters(self, metaclass):
+        debug.dbg('Unprocessed metaclass %s', metaclass)
+        return []
+
+    @evaluator_method_cache(default=NO_CONTEXTS)
+    def get_metaclasses(self):
+        args = self._get_bases_arguments()
+        if args is not None:
+            m = [value for key, value in args.unpack() if key == 'metaclass']
+            metaclasses = ContextSet.from_sets(lazy_context.infer() for lazy_context in m)
+            metaclasses = ContextSet(m for m in metaclasses if m.is_class())
+            if metaclasses:
+                return metaclasses
+
+        for lazy_base in self.py__bases__():
+            for context in lazy_base.infer():
+                if context.is_class():
+                    contexts = context.get_metaclasses()
+                    if contexts:
+                        return contexts
+        return NO_CONTEXTS

jedi/evaluate/context/module.py

@@ -9,6 +9,8 @@ from jedi.evaluate import compiled
 from jedi.evaluate.base_context import TreeContext
 from jedi.evaluate.names import SubModuleName
 from jedi.evaluate.helpers import contexts_from_qualified_names
+from jedi.evaluate.compiled import create_simple_object
+from jedi.evaluate.base_context import ContextSet
 
 
 class _ModuleAttributeName(AbstractNameDefinition):
@@ -17,11 +19,20 @@ class _ModuleAttributeName(AbstractNameDefinition):
     """
     api_type = u'instance'
 
-    def __init__(self, parent_module, string_name):
+    def __init__(self, parent_module, string_name, string_value=None):
         self.parent_context = parent_module
         self.string_name = string_name
+        self._string_value = string_value
 
     def infer(self):
+        if self._string_value is not None:
+            s = self._string_value
+            if self.parent_context.evaluator.environment.version_info.major == 2 \
+                    and not isinstance(s, bytes):
+                s = s.encode('utf-8')
+            return ContextSet([
+                create_simple_object(self.parent_context.evaluator, s)
+            ])
         return compiled.get_string_context_set(self.parent_context.evaluator)
 
 
@@ -132,9 +143,13 @@ class ModuleMixin(SubModuleDictMixin):
 
     @evaluator_method_cache()
     def _module_attributes_dict(self):
-        names = ['__file__', '__package__', '__doc__', '__name__']
+        names = ['__package__', '__doc__', '__name__']
         # All the additional module attributes are strings.
-        return dict((n, _ModuleAttributeName(self, n)) for n in names)
+        dct = dict((n, _ModuleAttributeName(self, n)) for n in names)
+        file = self.py__file__()
+        if file is not None:
+            dct['__file__'] = _ModuleAttributeName(self, '__file__', file)
+        return dct
 
     def iter_star_filters(self, search_global=False):
         for star_module in self.star_imports():

jedi/evaluate/docstrings.py

@@ -51,11 +51,8 @@ def _get_numpy_doc_string_cls():
     global _numpy_doc_string_cache
     if isinstance(_numpy_doc_string_cache, (ImportError, SyntaxError)):
         raise _numpy_doc_string_cache
-    try:
-        from numpydoc.docscrape import NumpyDocString
-        _numpy_doc_string_cache = NumpyDocString
-    except (ImportError, SyntaxError) as e:
-        raise
+    from numpydoc.docscrape import NumpyDocString
+    _numpy_doc_string_cache = NumpyDocString
     return _numpy_doc_string_cache
 
 

jedi/evaluate/dynamic.py

@@ -17,7 +17,6 @@ It works as follows:
 - execute these calls and check the input.
 """
 
-from parso.python import tree
 from jedi import settings
 from jedi import debug
 from jedi.evaluate.cache import evaluator_function_cache

jedi/evaluate/filters.py

@@ -386,7 +386,7 @@ def get_global_filters(evaluator, context, until_position, origin_scope):
     >>> list(filters[1].values())  # package modules -> Also empty.
     []
     >>> sorted(name.string_name for name in filters[2].values())  # Module attributes
-    ['__doc__', '__file__', '__name__', '__package__']
+    ['__doc__', '__name__', '__package__']
 
     Finally, it yields the builtin filter, if `include_builtin` is
     true (default).
@@ -409,5 +409,4 @@ def get_global_filters(evaluator, context, until_position, origin_scope):
         context = context.parent_context
 
     # Add builtins to the global scope.
-    for filter in evaluator.builtins_module.get_filters():
-        yield filter
+    yield next(evaluator.builtins_module.get_filters())

jedi/evaluate/gradual/annotation.py

@@ -14,7 +14,9 @@ from jedi.evaluate.cache import evaluator_method_cache
 from jedi.evaluate.base_context import ContextSet, NO_CONTEXTS
 from jedi.evaluate.gradual.typing import TypeVar, LazyGenericClass, \
     AbstractAnnotatedClass
+from jedi.evaluate.gradual.typing import GenericClass
 from jedi.evaluate.helpers import is_string
+from jedi.evaluate.compiled import builtin_from_name
 from jedi import debug
 from jedi import parser_utils
 
@@ -106,6 +108,25 @@ def _split_comment_param_declaration(decl_text):
 
 @evaluator_method_cache()
 def infer_param(execution_context, param):
+    contexts = _infer_param(execution_context, param)
+    evaluator = execution_context.evaluator
+    if param.star_count == 1:
+        tuple_ = builtin_from_name(evaluator, 'tuple')
+        return ContextSet([GenericClass(
+            tuple_,
+            generics=(contexts,),
+        ) for c in contexts])
+    elif param.star_count == 2:
+        dct = builtin_from_name(evaluator, 'dict')
+        return ContextSet([GenericClass(
+            dct,
+            generics=(ContextSet([builtin_from_name(evaluator, 'str')]), contexts),
+        ) for c in contexts])
+        pass
+    return contexts
+
+
+def _infer_param(execution_context, param):
     """
     Infers the type of a function parameter, using type annotations.
     """

jedi/evaluate/gradual/conversion.py

@@ -40,7 +40,8 @@ def _stub_to_python_context_set(stub_context, ignore_compiled=False):
 
 
 def _infer_from_stub(stub_module, qualified_names, ignore_compiled):
-    assert isinstance(stub_module, StubModuleContext), stub_module
+    from jedi.evaluate.compiled.mixed import MixedObject
+    assert isinstance(stub_module, (StubModuleContext, MixedObject)), stub_module
     non_stubs = stub_module.non_stub_context_set
     if ignore_compiled:
         non_stubs = non_stubs.filter(lambda c: not c.is_compiled())

jedi/evaluate/gradual/typeshed.py

@@ -1,5 +1,6 @@
 import os
 import re
+from functools import wraps
 
 from jedi.file_io import FileIO
 from jedi._compatibility import FileNotFoundError, cast_path
@@ -87,6 +88,7 @@ def _cache_stub_file_map(version_info):
 
 
 def import_module_decorator(func):
+    @wraps(func)
     def wrapper(evaluator, import_names, parent_module_context, sys_path, prefer_stubs):
         try:
             python_context_set = evaluator.module_cache.get(import_names)

jedi/evaluate/gradual/typing.py

@@ -10,7 +10,7 @@ from jedi import debug
 from jedi.evaluate.cache import evaluator_method_cache
 from jedi.evaluate.compiled import builtin_from_name
 from jedi.evaluate.base_context import ContextSet, NO_CONTEXTS, Context, \
-    iterator_to_context_set, HelperContextMixin, ContextWrapper
+    iterator_to_context_set, ContextWrapper, LazyContextWrapper
 from jedi.evaluate.lazy_context import LazyKnownContexts
 from jedi.evaluate.context.iterable import SequenceLiteralContext
 from jedi.evaluate.arguments import repack_with_argument_clinic
@@ -209,6 +209,9 @@ class _TypingClassMixin(object):
             self.evaluator.builtins_module.py__getattribute__('object')
         )]
 
+    def get_metaclasses(self):
+        return []
+
 
 class TypingClassContextWithIndex(_TypingClassMixin, TypingContextWithIndex, ClassMixin):
     pass
@@ -241,9 +244,9 @@ def _iter_over_arguments(maybe_tuple_context, defining_context):
         yield ContextSet(resolve_forward_references(context_set))
 
 
-class TypeAlias(HelperContextMixin):
-    def __init__(self, evaluator, parent_context, origin_tree_name, actual):
-        self.evaluator = evaluator
+class TypeAlias(LazyContextWrapper):
+    def __init__(self, parent_context, origin_tree_name, actual):
+        self.evaluator = parent_context.evaluator
         self.parent_context = parent_context
         self._origin_tree_name = origin_tree_name
         self._actual = actual  # e.g. builtins.list
@@ -255,14 +258,10 @@ class TypeAlias(HelperContextMixin):
     def py__name__(self):
         return self.name.string_name
 
-    def __getattr__(self, name):
-        return getattr(self._get_type_alias_class(), name)
-
     def __repr__(self):
         return '<%s: %s>' % (self.__class__.__name__, self._actual)
 
-    @evaluator_method_cache()
-    def _get_type_alias_class(self):
+    def _get_wrapped_context(self):
         module_name, class_name = self._actual.split('.')
         if self.evaluator.environment.version_info.major == 2 and module_name == 'builtins':
             module_name = '__builtin__'

jedi/evaluate/imports.py

@@ -21,7 +21,7 @@ from jedi._compatibility import (FileNotFoundError, ImplicitNSInfo,
                                  force_unicode, unicode)
 from jedi import debug
 from jedi import settings
-from jedi.file_io import KnownContentFileIO, FolderIO, FileIO
+from jedi.file_io import KnownContentFileIO, FileIO
 from jedi.parser_utils import get_cached_code_lines
 from jedi.evaluate import sys_path
 from jedi.evaluate import helpers
@@ -33,6 +33,7 @@ from jedi.evaluate.names import ImportName, SubModuleName
 from jedi.evaluate.base_context import ContextSet, NO_CONTEXTS
 from jedi.evaluate.gradual.typeshed import import_module_decorator
 from jedi.evaluate.context.module import iter_module_names
+from jedi.plugins import plugin_manager
 
 
 class ModuleCache(object):
@@ -371,6 +372,7 @@ class Importer(object):
         return names
 
 
+@plugin_manager.decorate()
 @import_module_decorator
 def import_module(evaluator, import_names, parent_module_context, sys_path):
     """

jedi/evaluate/names.py

@@ -3,7 +3,7 @@ from abc import abstractmethod
 from parso.tree import search_ancestor
 
 from jedi._compatibility import Parameter
-from jedi.evaluate.base_context import ContextSet
+from jedi.evaluate.base_context import ContextSet, NO_CONTEXTS
 from jedi.cache import memoize_method
 
 
@@ -58,6 +58,23 @@ class AbstractNameDefinition(object):
         return self.parent_context.api_type
 
 
+class AbstractArbitraryName(AbstractNameDefinition):
+    """
+    When you e.g. want to complete dicts keys, you probably want to complete
+    string literals, which is not really a name, but for Jedi we use this
+    concept of Name for completions as well.
+    """
+    is_context_name = False
+
+    def __init__(self, evaluator, string):
+        self.evaluator = evaluator
+        self.string_name = string
+        self.parent_context = evaluator.builtins_module
+
+    def infer(self):
+        return NO_CONTEXTS
+
+
 class AbstractTreeName(AbstractNameDefinition):
     def __init__(self, parent_context, tree_name):
         self.parent_context = parent_context
@@ -150,8 +167,18 @@ class TreeNameDefinition(AbstractTreeName):
         return self._API_TYPES.get(definition.type, 'statement')
 
 
-class ParamNameInterface(object):
-    api_type = u'param'
+class _ParamMixin(object):
+    def maybe_positional_argument(self, include_star=True):
+        options = [Parameter.POSITIONAL_ONLY, Parameter.POSITIONAL_OR_KEYWORD]
+        if include_star:
+            options.append(Parameter.VAR_POSITIONAL)
+        return self.get_kind() in options
+
+    def maybe_keyword_argument(self, include_stars=True):
+        options = [Parameter.KEYWORD_ONLY, Parameter.POSITIONAL_OR_KEYWORD]
+        if include_stars:
+            options.append(Parameter.VAR_KEYWORD)
+        return self.get_kind() in options
 
     def _kind_string(self):
         kind = self.get_kind()
@@ -161,21 +188,74 @@ class ParamNameInterface(object):
             return '**'
         return ''
 
+
+class ParamNameInterface(_ParamMixin):
+    api_type = u'param'
+
     def get_kind(self):
         raise NotImplementedError
 
     def to_string(self):
         raise NotImplementedError
 
+    def get_param(self):
+        # TODO document better where this is used and when. Currently it has
+        #      very limited use, but is still in use. It's currently not even
+        #      clear what values would be allowed.
+        return None
 
-class ParamName(ParamNameInterface, AbstractTreeName):
-    def __init__(self, parent_context, tree_name):
-        self.parent_context = parent_context
-        self.tree_name = tree_name
+    @property
+    def star_count(self):
+        kind = self.get_kind()
+        if kind == Parameter.VAR_POSITIONAL:
+            return 1
+        if kind == Parameter.VAR_KEYWORD:
+            return 2
+        return 0
 
+
+class BaseTreeParamName(ParamNameInterface, AbstractTreeName):
+    annotation_node = None
+    default_node = None
+
+    def to_string(self):
+        output = self._kind_string() + self.string_name
+        annotation = self.annotation_node
+        default = self.default_node
+        if annotation is not None:
+            output += ': ' + annotation.get_code(include_prefix=False)
+        if default is not None:
+            output += '=' + default.get_code(include_prefix=False)
+        return output
+
+
+class ParamName(BaseTreeParamName):
     def _get_param_node(self):
         return search_ancestor(self.tree_name, 'param')
 
+    @property
+    def annotation_node(self):
+        return self._get_param_node().annotation
+
+    def infer_annotation(self, execute_annotation=True):
+        node = self.annotation_node
+        if node is None:
+            return NO_CONTEXTS
+        contexts = self.parent_context.parent_context.eval_node(node)
+        if execute_annotation:
+            contexts = contexts.execute_annotation()
+        return contexts
+
+    def infer_default(self):
+        node = self.default_node
+        if node is None:
+            return NO_CONTEXTS
+        return self.parent_context.parent_context.eval_node(node)
+
+    @property
+    def default_node(self):
+        return self._get_param_node().default
+
     @property
     def string_name(self):
         name = self.tree_name.value
@@ -213,15 +293,6 @@ class ParamName(ParamNameInterface, AbstractTreeName):
                         param_appeared = True
         return Parameter.POSITIONAL_OR_KEYWORD
 
-    def to_string(self):
-        output = self._kind_string() + self.string_name
-        param_node = self._get_param_node()
-        if param_node.annotation is not None:
-            output += ': ' + param_node.annotation.get_code(include_prefix=False)
-        if param_node.default is not None:
-            output += '=' + param_node.default.get_code(include_prefix=False)
-        return output
-
     def infer(self):
         return self.get_param().infer()
 
@@ -231,6 +302,17 @@ class ParamName(ParamNameInterface, AbstractTreeName):
         return params[param_node.position_index]
 
 
+class ParamNameWrapper(_ParamMixin):
+    def __init__(self, param_name):
+        self._wrapped_param_name = param_name
+
+    def __getattr__(self, name):
+        return getattr(self._wrapped_param_name, name)
+
+    def __repr__(self):
+        return '<%s: %s>' % (self.__class__.__name__, self._wrapped_param_name)
+
+
 class ImportName(AbstractNameDefinition):
     start_pos = (1, 0)
     _level = 0

jedi/evaluate/signature.py

@@ -1,24 +1,13 @@
 from jedi._compatibility import Parameter
+from jedi.cache import memoize_method
 
 
-class AbstractSignature(object):
-    def __init__(self, context, is_bound=False):
-        self.context = context
-        self.is_bound = is_bound
-
-    @property
-    def name(self):
-        return self.context.name
-
-    @property
-    def annotation_string(self):
-        return ''
-
+class _SignatureMixin(object):
     def to_string(self):
         def param_strings():
             is_positional = False
             is_kw_only = False
-            for n in self.get_param_names():
+            for n in self.get_param_names(resolve_stars=True):
                 kind = n.get_kind()
                 is_positional |= kind == Parameter.POSITIONAL_ONLY
                 if is_positional and kind != Parameter.POSITIONAL_ONLY:
@@ -42,15 +31,32 @@ class AbstractSignature(object):
             s += ' -> ' + annotation
         return s
 
-    def bind(self, context):
-        raise NotImplementedError
 
-    def get_param_names(self):
+class AbstractSignature(_SignatureMixin):
+    def __init__(self, context, is_bound=False):
+        self.context = context
+        self.is_bound = is_bound
+
+    @property
+    def name(self):
+        return self.context.name
+
+    @property
+    def annotation_string(self):
+        return ''
+
+    def get_param_names(self, resolve_stars=False):
         param_names = self._function_context.get_param_names()
         if self.is_bound:
             return param_names[1:]
         return param_names
 
+    def bind(self, context):
+        raise NotImplementedError
+
+    def __repr__(self):
+        return '<%s: %s, %s>' % (self.__class__.__name__, self.context, self._function_context)
+
 
 class TreeSignature(AbstractSignature):
     def __init__(self, context, function_context=None, is_bound=False):
@@ -75,6 +81,14 @@ class TreeSignature(AbstractSignature):
             return ''
         return a.get_code(include_prefix=False)
 
+    @memoize_method
+    def get_param_names(self, resolve_stars=False):
+        params = super(TreeSignature, self).get_param_names(resolve_stars=False)
+        if resolve_stars:
+            from jedi.evaluate.star_args import process_params
+            params = process_params(params)
+        return params
+
 
 class BuiltinSignature(AbstractSignature):
     def __init__(self, context, return_string, is_bound=False):
@@ -92,3 +106,11 @@ class BuiltinSignature(AbstractSignature):
     def bind(self, context):
         assert not self.is_bound
         return BuiltinSignature(context, self._return_string, is_bound=True)
+
+
+class SignatureWrapper(_SignatureMixin):
+    def __init__(self, wrapped_signature):
+        self._wrapped_signature = wrapped_signature
+
+    def __getattr__(self, name):
+        return getattr(self._wrapped_signature, name)

jedi/evaluate/star_args.py

@@ -0,0 +1,206 @@
+"""
+This module is responsible for evaluating *args and **kwargs for signatures.
+
+This means for example in this case::
+
+    def foo(a, b, c): ...
+
+    def bar(*args):
+        return foo(1, *args)
+
+The signature here for bar should be `bar(b, c)` instead of bar(*args).
+"""
+
+from jedi._compatibility import Parameter
+from jedi.evaluate.utils import to_list
+from jedi.evaluate.names import ParamNameWrapper
+
+
+def _iter_nodes_for_param(param_name):
+    from parso.python.tree import search_ancestor
+    from jedi.evaluate.arguments import TreeArguments
+
+    execution_context = param_name.parent_context
+    function_node = execution_context.tree_node
+    module_node = function_node.get_root_node()
+    start = function_node.children[-1].start_pos
+    end = function_node.children[-1].end_pos
+    for name in module_node.get_used_names().get(param_name.string_name):
+        if start <= name.start_pos < end:
+            # Is used in the function
+            argument = name.parent
+            if argument.type == 'argument' \
+                    and argument.children[0] == '*' * param_name.star_count:
+                # No support for Python <= 3.4 here, but they are end-of-life
+                # anyway
+                trailer = search_ancestor(argument, 'trailer')
+                if trailer is not None:  # Make sure we're in a function
+                    context = execution_context.create_context(trailer)
+                    if _goes_to_param_name(param_name, context, name):
+                        contexts = _to_callables(context, trailer)
+
+                        args = TreeArguments.create_cached(
+                            execution_context.evaluator,
+                            context=context,
+                            argument_node=trailer.children[1],
+                            trailer=trailer,
+                        )
+                        for c in contexts:
+                            yield c, args
+                    else:
+                        assert False
+
+
+def _goes_to_param_name(param_name, context, potential_name):
+    if potential_name.type != 'name':
+        return False
+    from jedi.evaluate.names import TreeNameDefinition
+    found = TreeNameDefinition(context, potential_name).goto()
+    return any(param_name.parent_context == p.parent_context
+               and param_name.start_pos == p.start_pos
+               for p in found)
+
+
+def _to_callables(context, trailer):
+    from jedi.evaluate.syntax_tree import eval_trailer
+
+    atom_expr = trailer.parent
+    index = atom_expr.children[0] == 'await'
+    # Eval atom first
+    contexts = context.eval_node(atom_expr.children[index])
+    for trailer2 in atom_expr.children[index + 1:]:
+        if trailer == trailer2:
+            break
+        contexts = eval_trailer(context, contexts, trailer2)
+    return contexts
+
+
+def _remove_given_params(arguments, param_names):
+    count = 0
+    used_keys = set()
+    for key, _ in arguments.unpack():
+        if key is None:
+            count += 1
+        else:
+            used_keys.add(key)
+
+    for p in param_names:
+        if count and p.maybe_positional_argument():
+            count -= 1
+            continue
+        if p.string_name in used_keys and p.maybe_keyword_argument():
+            continue
+        yield p
+
+
+@to_list
+def process_params(param_names, star_count=3):  # default means both * and **
+    used_names = set()
+    arg_callables = []
+    kwarg_callables = []
+
+    kw_only_names = []
+    kwarg_names = []
+    arg_names = []
+    original_arg_name = None
+    original_kwarg_name = None
+    for p in param_names:
+        kind = p.get_kind()
+        if kind == Parameter.VAR_POSITIONAL:
+            if star_count & 1:
+                arg_callables = _iter_nodes_for_param(p)
+                original_arg_name = p
+        elif p.get_kind() == Parameter.VAR_KEYWORD:
+            if star_count & 2:
+                kwarg_callables = list(_iter_nodes_for_param(p))
+                original_kwarg_name = p
+        elif kind == Parameter.KEYWORD_ONLY:
+            if star_count & 2:
+                kw_only_names.append(p)
+        elif kind == Parameter.POSITIONAL_ONLY:
+            if star_count & 1:
+                yield p
+        else:
+            if star_count == 1:
+                yield ParamNameFixedKind(p, Parameter.POSITIONAL_ONLY)
+            elif star_count == 2:
+                kw_only_names.append(ParamNameFixedKind(p, Parameter.KEYWORD_ONLY))
+            else:
+                used_names.add(p.string_name)
+                yield p
+
+    longest_param_names = ()
+    found_arg_signature = False
+    found_kwarg_signature = False
+    for func_and_argument in arg_callables:
+        func, arguments = func_and_argument
+        new_star_count = star_count
+        if func_and_argument in kwarg_callables:
+            kwarg_callables.remove(func_and_argument)
+        else:
+            new_star_count = 1
+
+        for signature in func.get_signatures():
+            found_arg_signature = True
+            if new_star_count == 3:
+                found_kwarg_signature = True
+            args_for_this_func = []
+            for p in process_params(
+                    list(_remove_given_params(
+                        arguments,
+                        signature.get_param_names(resolve_stars=False)
+                    )), new_star_count):
+                if p.get_kind() == Parameter.VAR_KEYWORD:
+                    kwarg_names.append(p)
+                elif p.get_kind() == Parameter.VAR_POSITIONAL:
+                    arg_names.append(p)
+                elif p.get_kind() == Parameter.KEYWORD_ONLY:
+                    kw_only_names.append(p)
+                else:
+                    args_for_this_func.append(p)
+            if len(args_for_this_func) > len(longest_param_names):
+                longest_param_names = args_for_this_func
+
+    for p in longest_param_names:
+        if star_count == 1 and p.get_kind() != Parameter.VAR_POSITIONAL:
+            yield ParamNameFixedKind(p, Parameter.POSITIONAL_ONLY)
+        else:
+            if p.get_kind() == Parameter.POSITIONAL_OR_KEYWORD:
+                used_names.add(p.string_name)
+            yield p
+
+    if not found_arg_signature and original_arg_name is not None:
+        yield original_arg_name
+    elif arg_names:
+        yield arg_names[0]
+
+    for p in kw_only_names:
+        if p.string_name in used_names:
+            continue
+        yield p
+        used_names.add(p.string_name)
+
+    for func, arguments in kwarg_callables:
+        for signature in func.get_signatures():
+            found_kwarg_signature = True
+            for p in process_params(
+                    list(_remove_given_params(
+                        arguments,
+                        signature.get_param_names(resolve_stars=False)
+                    )), star_count=2):
+                if p.get_kind() != Parameter.KEYWORD_ONLY or not kwarg_names:
+                    yield p
+
+    if not found_kwarg_signature and original_kwarg_name is not None:
+        yield original_kwarg_name
+    elif kwarg_names:
+        yield kwarg_names[0]
+
+
+class ParamNameFixedKind(ParamNameWrapper):
+    def __init__(self, param_name, new_kind):
+        super(ParamNameFixedKind, self).__init__(param_name)
+        self._new_kind = new_kind
+
+    def get_kind(self):
+        return self._new_kind

jedi/evaluate/syntax_tree.py

@@ -26,6 +26,8 @@ from jedi.evaluate.compiled.access import COMPARISON_OPERATORS
 from jedi.evaluate.cache import evaluator_method_cache
 from jedi.evaluate.gradual.stub_context import VersionInfo
 from jedi.evaluate.gradual import annotation
+from jedi.evaluate.context.decorator import Decoratee
+from jedi.plugins import plugin_manager
 
 
 def _limit_context_infers(func):
@@ -148,28 +150,28 @@ def eval_node(context, element):
         return eval_or_test(context, element)
 
 
-def eval_trailer(context, base_contexts, trailer):
+def eval_trailer(context, atom_contexts, trailer):
     trailer_op, node = trailer.children[:2]
     if node == ')':  # `arglist` is optional.
         node = None
 
     if trailer_op == '[':
         trailer_op, node, _ = trailer.children
-        return base_contexts.get_item(
+        return atom_contexts.get_item(
             eval_subscript_list(context.evaluator, context, node),
             ContextualizedNode(context, trailer)
         )
     else:
-        debug.dbg('eval_trailer: %s in %s', trailer, base_contexts)
+        debug.dbg('eval_trailer: %s in %s', trailer, atom_contexts)
         if trailer_op == '.':
-            return base_contexts.py__getattribute__(
+            return atom_contexts.py__getattribute__(
                 name_context=context,
                 name_or_str=node
             )
         else:
             assert trailer_op == '(', 'trailer_op is actually %s' % trailer_op
             args = arguments.TreeArguments(context.evaluator, context, node, trailer)
-            return base_contexts.execute(args)
+            return atom_contexts.execute(args)
 
 
 def eval_atom(context, atom):
@@ -544,6 +546,7 @@ def _remove_statements(evaluator, context, stmt, name):
     return eval_expr_stmt(context, stmt, seek_name=name)
 
 
+@plugin_manager.decorate()
 def tree_name_to_contexts(evaluator, context, tree_name):
     context_set = NO_CONTEXTS
     module_node = context.get_root_context().tree_node
@@ -666,6 +669,8 @@ def _apply_decorators(context, node):
                 return initial
 
         debug.dbg('decorator end %s', values, color="MAGENTA")
+    if values != initial:
+        return ContextSet([Decoratee(c, decoratee_context) for c in values])
     return values
 
 

jedi/parser_utils.py

@@ -5,6 +5,7 @@ from weakref import WeakKeyDictionary
 
 from parso.python import tree
 from parso.cache import parser_cache
+from parso import split_lines
 
 from jedi._compatibility import literal_eval, force_unicode
 
@@ -278,3 +279,19 @@ def get_cached_code_lines(grammar, path):
     to do this, but we avoid splitting all the lines again.
     """
     return parser_cache[grammar._hashed][path].lines
+
+
+def cut_value_at_position(leaf, position):
+    """
+    Cuts of the value of the leaf at position
+    """
+    lines = split_lines(leaf.value, keepends=True)[:position[0] - leaf.line + 1]
+    column = position[1]
+    if leaf.line == position[0]:
+        column -= leaf.column
+    lines[-1] = lines[-1][:column]
+    return ''.join(lines)
+
+
+def get_string_quote(leaf):
+    return re.match('\w*("""|\'{3}|"|\')', leaf.value).group(1)

jedi/plugins/__init__.py

@@ -1,37 +1,47 @@
-from jedi.plugins.stdlib import StdlibPlugin
-from jedi.plugins.flask import FlaskPlugin
+from functools import wraps
 
 
 class _PluginManager(object):
-    def __init__(self, registered_plugin_classes=()):
-        self._registered_plugin_classes = list(registered_plugin_classes)
+    def __init__(self):
+        self._registered_plugins = []
+        self._cached_base_callbacks = {}
+        self._built_functions = {}
 
-    def register(self, plugin_class):
+    def register(self, *plugins):
         """
         Makes it possible to register your plugin.
         """
-        self._registered_plugins.append(plugin_class)
+        self._registered_plugins.extend(plugins)
+        self._build_functions()
 
-    def _build_chain(self, evaluator):
-        for plugin_class in self._registered_plugin_classes:
-            yield plugin_class(evaluator)
+    def decorate(self):
+        def decorator(callback):
+            @wraps(callback)
+            def wrapper(*args, **kwargs):
+                return built_functions[name](*args, **kwargs)
 
-    def get_callbacks(self, evaluator):
-        return _PluginCallbacks(self._build_chain(evaluator))
+            name = callback.__name__
+
+            assert name not in self._built_functions
+            built_functions = self._built_functions
+            built_functions[name] = callback
+            self._cached_base_callbacks[name] = callback
+
+            return wrapper
+
+        return decorator
+
+    def _build_functions(self):
+        for name, callback in self._cached_base_callbacks.items():
+            for plugin in reversed(self._registered_plugins):
+                # Need to reverse so the first plugin is run first.
+                try:
+                    func = getattr(plugin, name)
+                except AttributeError:
+                    pass
+                else:
+                    callback = func(callback)
+            self._built_functions[name] = callback
 
 
-class _PluginCallbacks(object):
-    def __init__(self, plugins):
-        self._plugins = list(plugins)
-
-    def decorate(self, name, callback):
-        for plugin in reversed(self._plugins):
-            # Need to reverse so the first plugin is run first.
-            callback = getattr(plugin, name)(callback)
-        return callback
-
-
-plugin_manager = _PluginManager([
-    StdlibPlugin,
-    FlaskPlugin,
-])
+plugin_manager = _PluginManager()

jedi/plugins/base.py

@@ -1,21 +0,0 @@
-class BasePlugin(object):
-    """
-    Plugins are created each time an evaluator is created.
-    """
-    def __init__(self, evaluator):
-        # In __init__ you can do some caching.
-        self._evaluator = evaluator
-
-    def execute(self, callback):
-        """
-        Decorates the execute(context, arguments) function.
-        """
-        return callback
-
-    def import_module(self, callback):
-        """
-        Decorates the
-        import_module(evaluator, import_path, sys_path, add_error_callback)
-        function.
-        """
-        return callback

jedi/plugins/flask.py

@@ -1,25 +1,21 @@
-from jedi.plugins.base import BasePlugin
-
-
-class FlaskPlugin(BasePlugin):
-    def import_module(self, callback):
-        """
-        Handle "magic" Flask extension imports:
-        ``flask.ext.foo`` is really ``flask_foo`` or ``flaskext.foo``.
-        """
-        def wrapper(evaluator, import_names, module_context, *args, **kwargs):
-            if len(import_names) == 3 and import_names[:2] == ('flask', 'ext'):
-                # New style.
-                ipath = (u'flask_' + import_names[2]),
-                context_set = callback(evaluator, ipath, None, *args, **kwargs)
-                if context_set:
-                    return context_set
-                context_set = callback(evaluator, (u'flaskext',), None, *args, **kwargs)
-                return callback(
-                    evaluator,
-                    (u'flaskext', import_names[2]),
-                    next(iter(context_set)),
-                    *args, **kwargs
-                )
-            return callback(evaluator, import_names, module_context, *args, **kwargs)
-        return wrapper
+def import_module(callback):
+    """
+    Handle "magic" Flask extension imports:
+    ``flask.ext.foo`` is really ``flask_foo`` or ``flaskext.foo``.
+    """
+    def wrapper(evaluator, import_names, module_context, *args, **kwargs):
+        if len(import_names) == 3 and import_names[:2] == ('flask', 'ext'):
+            # New style.
+            ipath = (u'flask_' + import_names[2]),
+            context_set = callback(evaluator, ipath, None, *args, **kwargs)
+            if context_set:
+                return context_set
+            context_set = callback(evaluator, (u'flaskext',), None, *args, **kwargs)
+            return callback(
+                evaluator,
+                (u'flaskext', import_names[2]),
+                next(iter(context_set)),
+                *args, **kwargs
+            )
+        return callback(evaluator, import_names, module_context, *args, **kwargs)
+    return wrapper

jedi/plugins/registry.py

@@ -0,0 +1,10 @@
+"""
+This is not a plugin, this is just the place were plugins are registered.
+"""
+
+from jedi.plugins import stdlib
+from jedi.plugins import flask
+from jedi.plugins import plugin_manager
+
+
+plugin_manager.register(stdlib, flask)

jedi/plugins/stdlib.py

@@ -10,10 +10,11 @@ the standard library. The usual way to understand the standard library is the
 compiled module that returns the types for C-builtins.
 """
 import parso
+import os
 
-from jedi._compatibility import force_unicode
-from jedi.plugins.base import BasePlugin
+from jedi._compatibility import force_unicode, Parameter
 from jedi import debug
+from jedi.evaluate.utils import safe_property
 from jedi.evaluate.helpers import get_str_or_none
 from jedi.evaluate.arguments import ValuesArguments, \
     repack_with_argument_clinic, AbstractArguments, TreeArgumentsWrapper
@@ -24,11 +25,16 @@ from jedi.evaluate.base_context import ContextualizedNode, \
     NO_CONTEXTS, ContextSet, ContextWrapper, LazyContextWrapper
 from jedi.evaluate.context import ClassContext, ModuleContext, \
     FunctionExecutionContext
+from jedi.evaluate.context.klass import ClassMixin
+from jedi.evaluate.context.function import FunctionMixin
 from jedi.evaluate.context import iterable
 from jedi.evaluate.lazy_context import LazyTreeContext, LazyKnownContext, \
     LazyKnownContexts
+from jedi.evaluate.names import ContextName, BaseTreeParamName
 from jedi.evaluate.syntax_tree import is_string
-from jedi.evaluate.filters import AttributeOverwrite, publish_method
+from jedi.evaluate.filters import AttributeOverwrite, publish_method, \
+    ParserTreeFilter, DictFilter
+from jedi.evaluate.signature import AbstractSignature, SignatureWrapper
 
 
 # Copied from Python 3.6's stdlib.
@@ -98,45 +104,48 @@ _NAMEDTUPLE_FIELD_TEMPLATE = '''\
 '''
 
 
-class StdlibPlugin(BasePlugin):
-    def execute(self, callback):
-        def wrapper(context, arguments):
-            try:
-                obj_name = context.name.string_name
-            except AttributeError:
-                pass
-            else:
-                if context.parent_context == self._evaluator.builtins_module:
-                    module_name = 'builtins'
-                elif context.parent_context is not None and context.parent_context.is_module():
-                    module_name = context.parent_context.py__name__()
-                else:
-                    return callback(context, arguments=arguments)
-
-                if isinstance(context, BoundMethod):
-                    if module_name == 'builtins':
-                        if context.py__name__() == '__get__':
-                            if context.class_context.py__name__() == 'property':
-                                return builtins_property(
-                                    context,
-                                    arguments=arguments
-                                )
-                        elif context.py__name__() in ('deleter', 'getter', 'setter'):
-                            if context.class_context.py__name__() == 'property':
-                                return ContextSet([context.instance])
-
-                    return callback(context, arguments=arguments)
-
-                # for now we just support builtin functions.
-                try:
-                    func = _implemented[module_name][obj_name]
-                except KeyError:
-                    pass
-                else:
-                    return func(context, arguments=arguments)
+def execute(callback):
+    def wrapper(context, arguments):
+        def call():
             return callback(context, arguments=arguments)
 
-        return wrapper
+        try:
+            obj_name = context.name.string_name
+        except AttributeError:
+            pass
+        else:
+            if context.parent_context == context.evaluator.builtins_module:
+                module_name = 'builtins'
+            elif context.parent_context is not None and context.parent_context.is_module():
+                module_name = context.parent_context.py__name__()
+            else:
+                return call()
+
+            if isinstance(context, BoundMethod):
+                if module_name == 'builtins':
+                    if context.py__name__() == '__get__':
+                        if context.class_context.py__name__() == 'property':
+                            return builtins_property(
+                                context,
+                                arguments=arguments,
+                                callback=call,
+                            )
+                    elif context.py__name__() in ('deleter', 'getter', 'setter'):
+                        if context.class_context.py__name__() == 'property':
+                            return ContextSet([context.instance])
+
+                return call()
+
+            # for now we just support builtin functions.
+            try:
+                func = _implemented[module_name][obj_name]
+            except KeyError:
+                pass
+            else:
+                return func(context, arguments=arguments, callback=call)
+        return call()
+
+    return wrapper
 
 
 def _follow_param(evaluator, arguments, index):
@@ -149,15 +158,18 @@ def _follow_param(evaluator, arguments, index):
 
 
 def argument_clinic(string, want_obj=False, want_context=False,
-                    want_arguments=False, want_evaluator=False):
+                    want_arguments=False, want_evaluator=False,
+                    want_callback=False):
     """
     Works like Argument Clinic (PEP 436), to validate function params.
     """
 
     def f(func):
-        @repack_with_argument_clinic(string, keep_arguments_param=True)
+        @repack_with_argument_clinic(string, keep_arguments_param=True,
+                                     keep_callback_param=True)
         def wrapper(obj, *args, **kwargs):
             arguments = kwargs.pop('arguments')
+            callback = kwargs.pop('callback')
             assert not kwargs  # Python 2...
             debug.dbg('builtin start %s' % obj, color='MAGENTA')
             result = NO_CONTEXTS
@@ -169,6 +181,8 @@ def argument_clinic(string, want_obj=False, want_context=False,
                 kwargs['evaluator'] = obj.evaluator
             if want_arguments:
                 kwargs['arguments'] = arguments
+            if want_callback:
+                kwargs['callback'] = callback
             result = func(*args, **kwargs)
             debug.dbg('builtin end: %s', result, color='MAGENTA')
             return result
@@ -378,6 +392,9 @@ class ClassMethodGet(AttributeOverwrite, ContextWrapper):
         self._class = klass
         self._function = function
 
+    def get_signatures(self):
+        return self._function.get_signatures()
+
     def get_object(self):
         return self._wrapped_context
 
@@ -405,7 +422,7 @@ def builtins_classmethod(functions, obj, arguments):
     )
 
 
-def collections_namedtuple(obj, arguments):
+def collections_namedtuple(obj, arguments, callback):
     """
     Implementation of the namedtuple function.
 
@@ -428,14 +445,16 @@ def collections_namedtuple(obj, arguments):
     if not param_contexts:
         return NO_CONTEXTS
     _fields = list(param_contexts)[0]
-    if isinstance(_fields, compiled.CompiledValue):
-        fields = force_unicode(_fields.get_safe_value()).replace(',', ' ').split()
+    string = get_str_or_none(_fields)
+    if string is not None:
+        fields = force_unicode(string).replace(',', ' ').split()
     elif isinstance(_fields, iterable.Sequence):
         fields = [
-            force_unicode(v.get_safe_value())
+            force_unicode(get_str_or_none(v))
             for lazy_context in _fields.py__iter__()
-            for v in lazy_context.infer() if is_string(v)
+            for v in lazy_context.infer()
         ]
+        fields = [f for f in fields if f is not None]
     else:
         return NO_CONTEXTS
 
@@ -471,17 +490,49 @@ class PartialObject(object):
     def __getattr__(self, name):
         return getattr(self._actual_context, name)
 
-    def py__call__(self, arguments):
-        key, lazy_context = next(self._arguments.unpack(), (None, None))
+    def _get_function(self, unpacked_arguments):
+        key, lazy_context = next(unpacked_arguments, (None, None))
         if key is not None or lazy_context is None:
             debug.warning("Partial should have a proper function %s", self._arguments)
+            return None
+        return lazy_context.infer()
+
+    def get_signatures(self):
+        unpacked_arguments = self._arguments.unpack()
+        func = self._get_function(unpacked_arguments)
+        if func is None:
+            return []
+
+        arg_count = 0
+        keys = set()
+        for key, _ in unpacked_arguments:
+            if key is None:
+                arg_count += 1
+            else:
+                keys.add(key)
+        return [PartialSignature(s, arg_count, keys) for s in func.get_signatures()]
+
+    def py__call__(self, arguments):
+        func = self._get_function(self._arguments.unpack())
+        if func is None:
             return NO_CONTEXTS
 
-        return lazy_context.infer().execute(
+        return func.execute(
             MergedPartialArguments(self._arguments, arguments)
         )
 
 
+class PartialSignature(SignatureWrapper):
+    def __init__(self, wrapped_signature, skipped_arg_count, skipped_arg_set):
+        super(PartialSignature, self).__init__(wrapped_signature)
+        self._skipped_arg_count = skipped_arg_count
+        self._skipped_arg_set = skipped_arg_set
+
+    def get_param_names(self, resolve_stars=False):
+        names = self._wrapped_signature.get_param_names()[self._skipped_arg_count:]
+        return [n for n in names if n.string_name not in self._skipped_arg_set]
+
+
 class MergedPartialArguments(AbstractArguments):
     def __init__(self, partial_arguments, call_arguments):
         self._partial_arguments = partial_arguments
@@ -498,7 +549,7 @@ class MergedPartialArguments(AbstractArguments):
             yield key_lazy_context
 
 
-def functools_partial(obj, arguments):
+def functools_partial(obj, arguments, callback):
     return ContextSet(
         PartialObject(instance, arguments)
         for instance in obj.py__call__(arguments)
@@ -519,6 +570,66 @@ def _random_choice(sequences):
     )
 
 
+def _dataclass(obj, arguments, callback):
+    for c in _follow_param(obj.evaluator, arguments, 0):
+        if c.is_class():
+            return ContextSet([DataclassWrapper(c)])
+        else:
+            return ContextSet([obj])
+    return NO_CONTEXTS
+
+
+class DataclassWrapper(ContextWrapper, ClassMixin):
+    def get_signatures(self):
+        param_names = []
+        for cls in reversed(list(self.py__mro__())):
+            if isinstance(cls, DataclassWrapper):
+                filter_ = cls.get_global_filter()
+                # .values ordering is not guaranteed, at least not in
+                # Python < 3.6, when dicts where not ordered, which is an
+                # implementation detail anyway.
+                for name in sorted(filter_.values(), key=lambda name: name.start_pos):
+                    d = name.tree_name.get_definition()
+                    annassign = d.children[1]
+                    if d.type == 'expr_stmt' and annassign.type == 'annassign':
+                        if len(annassign.children) < 4:
+                            default = None
+                        else:
+                            default = annassign.children[3]
+                        param_names.append(DataclassParamName(
+                            parent_context=cls.parent_context,
+                            tree_name=name.tree_name,
+                            annotation_node=annassign.children[1],
+                            default_node=default,
+                        ))
+        return [DataclassSignature(cls, param_names)]
+
+
+class DataclassSignature(AbstractSignature):
+    def __init__(self, context, param_names):
+        super(DataclassSignature, self).__init__(context)
+        self._param_names = param_names
+
+    def get_param_names(self, resolve_stars=False):
+        return self._param_names
+
+
+class DataclassParamName(BaseTreeParamName):
+    def __init__(self, parent_context, tree_name, annotation_node, default_node):
+        super(DataclassParamName, self).__init__(parent_context, tree_name)
+        self.annotation_node = annotation_node
+        self.default_node = default_node
+
+    def get_kind(self):
+        return Parameter.POSITIONAL_OR_KEYWORD
+
+    def infer(self):
+        if self.annotation_node is None:
+            return NO_CONTEXTS
+        else:
+            return self.parent_context.eval_node(self.annotation_node)
+
+
 class ItemGetterCallable(ContextWrapper):
     def __init__(self, instance, args_context_set):
         super(ItemGetterCallable, self).__init__(instance)
@@ -544,6 +655,33 @@ class ItemGetterCallable(ContextWrapper):
         return context_set
 
 
+@argument_clinic('func, /')
+def _functools_wraps(funcs):
+    return ContextSet(WrapsCallable(func) for func in funcs)
+
+
+class WrapsCallable(ContextWrapper):
+    # XXX this is not the correct wrapped context, it should be a weird
+    #     partials object, but it doesn't matter, because it's always used as a
+    #     decorator anyway.
+    @repack_with_argument_clinic('func, /')
+    def py__call__(self, funcs):
+        return ContextSet({Wrapped(func, self._wrapped_context) for func in funcs})
+
+
+class Wrapped(ContextWrapper, FunctionMixin):
+    def __init__(self, func, original_function):
+        super(Wrapped, self).__init__(func)
+        self._original_function = original_function
+
+    @property
+    def name(self):
+        return self._original_function.name
+
+    def get_signature_functions(self):
+        return [self]
+
+
 @argument_clinic('*args, /', want_obj=True, want_arguments=True)
 def _operator_itemgetter(args_context_set, obj, arguments):
     return ContextSet([
@@ -552,6 +690,44 @@ def _operator_itemgetter(args_context_set, obj, arguments):
     ])
 
 
+def _create_string_input_function(func):
+    @argument_clinic('string, /', want_obj=True, want_arguments=True)
+    def wrapper(strings, obj, arguments):
+        def iterate():
+            for context in strings:
+                s = get_str_or_none(context)
+                if s is not None:
+                    s = func(s)
+                    yield compiled.create_simple_object(context.evaluator, s)
+        contexts = ContextSet(iterate())
+        if contexts:
+            return contexts
+        return obj.py__call__(arguments)
+    return wrapper
+
+
+@argument_clinic('*args, /', want_callback=True)
+def _os_path_join(args_set, callback):
+    if len(args_set) == 1:
+        string = u''
+        sequence, = args_set
+        is_first = True
+        for lazy_context in sequence.py__iter__():
+            string_contexts = lazy_context.infer()
+            if len(string_contexts) != 1:
+                break
+            s = get_str_or_none(next(iter(string_contexts)))
+            if s is None:
+                break
+            if not is_first:
+                string += os.path.sep
+            string += force_unicode(s)
+            is_first = False
+        else:
+            return ContextSet([compiled.create_simple_object(sequence.evaluator, string)])
+    return callback()
+
+
 _implemented = {
     'builtins': {
         'getattr': builtins_getattr,
@@ -569,15 +745,15 @@ _implemented = {
         'deepcopy': _return_first_param,
     },
     'json': {
-        'load': lambda obj, arguments: NO_CONTEXTS,
-        'loads': lambda obj, arguments: NO_CONTEXTS,
+        'load': lambda obj, arguments, callback: NO_CONTEXTS,
+        'loads': lambda obj, arguments, callback: NO_CONTEXTS,
     },
     'collections': {
         'namedtuple': collections_namedtuple,
     },
     'functools': {
         'partial': functools_partial,
-        'wraps': _return_first_param,
+        'wraps': _functools_wraps,
     },
     '_weakref': {
         'proxy': _return_first_param,
@@ -597,10 +773,63 @@ _implemented = {
         # The _alias function just leads to some annoying type inference.
         # Therefore, just make it return nothing, which leads to the stubs
         # being used instead. This only matters for 3.7+.
-        '_alias': lambda obj, arguments: NO_CONTEXTS,
+        '_alias': lambda obj, arguments, callback: NO_CONTEXTS,
     },
     'dataclasses': {
         # For now this works at least better than Jedi trying to understand it.
-        'dataclass': lambda obj, arguments: NO_CONTEXTS,
+        'dataclass': _dataclass
     },
+    'os.path': {
+        'dirname': _create_string_input_function(os.path.dirname),
+        'abspath': _create_string_input_function(os.path.abspath),
+        'relpath': _create_string_input_function(os.path.relpath),
+        'join': _os_path_join,
+    }
 }
+
+
+def get_metaclass_filters(func):
+    def wrapper(cls, metaclasses):
+        for metaclass in metaclasses:
+            if metaclass.py__name__() == 'EnumMeta' \
+                    and metaclass.get_root_context().py__name__() == 'enum':
+                filter_ = ParserTreeFilter(cls.evaluator, context=cls)
+                return [DictFilter({
+                    name.string_name: EnumInstance(cls, name).name for name in filter_.values()
+                })]
+        return func(cls, metaclasses)
+    return wrapper
+
+
+class EnumInstance(LazyContextWrapper):
+    def __init__(self, cls, name):
+        self.evaluator = cls.evaluator
+        self._cls = cls  # Corresponds to super().__self__
+        self._name = name
+        self.tree_node = self._name.tree_name
+
+    @safe_property
+    def name(self):
+        return ContextName(self, self._name.tree_name)
+
+    def _get_wrapped_context(self):
+        obj, = self._cls.execute_evaluated()
+        return obj
+
+    def get_filters(self, search_global=False, position=None, origin_scope=None):
+        yield DictFilter(dict(
+            name=compiled.create_simple_object(self.evaluator, self._name.string_name).name,
+            value=self._name,
+        ))
+        for f in self._get_wrapped_context().get_filters():
+            yield f
+
+
+def tree_name_to_contexts(func):
+    def wrapper(evaluator, context, tree_name):
+        if tree_name.value == 'sep' and context.is_module() and context.py__name__() == 'os.path':
+            return ContextSet({
+                compiled.create_simple_object(evaluator, os.path.sep),
+            })
+        return func(evaluator, context, tree_name)
+    return wrapper

jedi/utils.py

@@ -11,10 +11,7 @@ import re
 import os
 import sys
 
-from parso import split_lines
-
 from jedi import Interpreter
-from jedi.api.helpers import get_on_completion_name
 
 
 READLINE_DEBUG = False
@@ -86,23 +83,18 @@ def setup_readline(namespace_module=__main__):
                     logging.debug("Start REPL completion: " + repr(text))
                     interpreter = Interpreter(text, [namespace_module.__dict__])
 
-                    lines = split_lines(text)
-                    position = (len(lines), len(lines[-1]))
-                    name = get_on_completion_name(
-                        interpreter._module_node,
-                        lines,
-                        position
-                    )
-                    before = text[:len(text) - len(name)]
                     completions = interpreter.completions()
                     logging.debug("REPL completions: %s", completions)
+
+                    self.matches = [
+                        text[:len(text) - c._like_name_length] + c.name_with_symbols
+                        for c in completions
+                    ]
                 except:
                     logging.error("REPL Completion error:\n" + traceback.format_exc())
                     raise
                 finally:
                     sys.path.pop(0)
-
-                self.matches = [before + c.name_with_symbols for c in completions]
             try:
                 return self.matches[state]
             except IndexError:

test/completion/import_tree/recurse_class1.py

@@ -1,4 +1,4 @@
-import recurse_class2
+from . import recurse_class2
 
 class C(recurse_class2.C):
     def a(self):

test/completion/import_tree/recurse_class2.py

@@ -1,4 +1,4 @@
-import recurse_class1
+from . import recurse_class1
 
 class C(recurse_class1.C):
     pass

test/completion/pep0484_basic.py

@@ -165,3 +165,19 @@ def keyword_only(a: str, *, b: str):
     a.startswi
     #? ['startswith']
     b.startswi
+
+
+def argskwargs(*args: int, **kwargs: float):
+    """
+    This might be a bit confusing, but is part of the standard.
+    args is changed to Tuple[int] in this case and kwargs to Dict[str, float],
+    which makes sense if you think about it a bit.
+    """
+    #? tuple()
+    args
+    #? int()
+    args[0]
+    #? str()
+    next(iter(kwargs.keys()))
+    #? float()
+    kwargs['']

test/completion/stdlib.py

@@ -67,6 +67,18 @@ class X(): pass
 #? type
 type(X)
 
+# -----------------
+# type() calls with multiple parameters
+# -----------------
+
+X = type('X', (object,), dict(a=1))
+
+# Doesn't work yet.
+#?
+X.a
+#?
+X
+
 if os.path.isfile():
     #? ['abspath']
     fails = os.path.abspath
@@ -290,3 +302,31 @@ class Test(metaclass=Meta):
         result = super(Test, self).test_function()
         #? []
         result.
+
+# -----------------
+# Enum
+# -----------------
+
+# python >= 3.4
+import enum
+
+class X(enum.Enum):
+    attr_x = 3
+    attr_y = 2.0
+
+#? ['mro']
+X.mro
+#? ['attr_x', 'attr_y']
+X.attr_
+#? str()
+X.attr_x.name
+#? int()
+X.attr_x.value
+#? str()
+X.attr_y.name
+#? float()
+X.attr_y.value
+#? str()
+X().name
+#? float()
+X().attr_x.attr_y.value

test/test_api/test_call_signatures.py

@@ -315,7 +315,8 @@ def test_signature_is_definition(Script):
 
     # Now compare all the attributes that a CallSignature must also have.
     for attr_name in dir(definition):
-        dont_scan = ['defined_names', 'parent', 'goto_assignments', 'infer', 'params']
+        dont_scan = ['defined_names', 'parent', 'goto_assignments', 'infer',
+                     'params', 'get_signatures', 'execute']
         if attr_name.startswith('_') or attr_name in dont_scan:
             continue
 

test/test_api/test_classes.py

@@ -442,3 +442,20 @@ def test_builtin_module_with_path(Script):
     assert semlock.name == 'SemLock'
     assert semlock.line is None
     assert semlock.column is None
+
+
+@pytest.mark.parametrize(
+    'code, description', [
+        ('int', 'instance int'),
+        ('str.index', 'instance int'),
+        ('1', None),
+    ]
+)
+def test_execute(Script, code, description):
+    definition, = Script(code).goto_assignments()
+    definitions = definition.execute()
+    if description is None:
+        assert not definitions
+    else:
+        d, = definitions
+        assert d.description == description

test/test_api/test_completion.py

@@ -1,8 +1,9 @@
-import os
+from os.path import join, sep as s
 import sys
 from textwrap import dedent
 
 import pytest
+from ..helpers import root_dir
 
 
 def test_in_whitespace(Script):
@@ -69,8 +70,8 @@ def test_points_in_completion(Script):
 
 def test_loading_unicode_files_with_bad_global_charset(Script, monkeypatch, tmpdir):
     dirname = str(tmpdir.mkdir('jedi-test'))
-    filename1 = os.path.join(dirname, 'test1.py')
-    filename2 = os.path.join(dirname, 'test2.py')
+    filename1 = join(dirname, 'test1.py')
+    filename2 = join(dirname, 'test2.py')
     if sys.version_info < (3, 0):
         data = "# coding: latin-1\nfoo = 'm\xf6p'\n"
     else:
@@ -156,3 +157,111 @@ def test_with_stmt_error_recovery(Script):
 )
 def test_keyword_completion(Script, code, has_keywords):
     assert has_keywords == any(x.is_keyword for x in Script(code).completions())
+
+
+f1 = join(root_dir, 'example.py')
+f2 = join(root_dir, 'test', 'example.py')
+os_path = 'from os.path import *\n'
+# os.path.sep escaped
+se = s * 2 if s == '\\' else s
+
+
+@pytest.mark.parametrize(
+    'file, code, column, expected', [
+        # General tests / relative paths
+        (None, '"comp', None, ['ile', 'lex']),  # No files like comp
+        (None, '"test', None, [s]),
+        (None, '"test', 4, ['t' + s]),
+        ('example.py', '"test%scomp' % s, None, ['letion' + s]),
+        ('example.py', 'r"comp"', None, "A LOT"),
+        ('example.py', 'r"tes"', None, "A LOT"),
+        ('example.py', 'r"tes"', 5, ['t' + s]),
+        ('example.py', 'r" tes"', 6, []),
+        ('test%sexample.py' % se, 'r"tes"', 5, ['t' + s]),
+        ('test%sexample.py' % se, 'r"test%scomp"' % s, 5, ['t' + s]),
+        ('test%sexample.py' % se, 'r"test%scomp"' % s, 11, ['letion' + s]),
+        ('test%sexample.py' % se, '"%s"' % join('test', 'completion', 'basi'), 21, ['c.py']),
+        ('example.py', 'rb"' + join('..', 'jedi', 'tes'), None, ['t' + s]),
+
+        # Absolute paths
+        (None, '"' + join(root_dir, 'test', 'test_ca'), None, ['che.py"']),
+        (None, '"%s"' % join(root_dir, 'test', 'test_ca'), len(root_dir) + 14, ['che.py']),
+
+        # Longer quotes
+        ('example.py', 'r"""test', None, [s]),
+        ('example.py', 'r"""\ntest', None, []),
+        ('example.py', 'u"""tes\n', (1, 7), ['t' + s]),
+        ('example.py', '"""test%stest_cache.p"""' % s, 20, ['y']),
+        ('example.py', '"""test%stest_cache.p"""' % s, 19, ['py"""']),
+
+        # Adding
+        ('example.py', '"test" + "%stest_cac' % se, None, ['he.py"']),
+        ('example.py', '"test" + "%s" + "test_cac' % se, None, ['he.py"']),
+        ('example.py', 'x = 1 + "test', None, []),
+        ('example.py', 'x = f("te" + "st)', 16, [s]),
+        ('example.py', 'x = f("te" + "st', 16, [s]),
+        ('example.py', 'x = f("te" + "st"', 16, [s]),
+        ('example.py', 'x = f("te" + "st")', 16, [s]),
+        ('example.py', 'x = f("t" + "est")', 16, [s]),
+        # This is actually not correct, but for now leave it here, because of
+        # Python 2.
+        ('example.py', 'x = f(b"t" + "est")', 17, [s]),
+        ('example.py', '"test" + "', None, [s]),
+
+        # __file__
+        (f1, os_path + 'dirname(__file__) + "%stest' % s, None, [s]),
+        (f2, os_path + 'dirname(__file__) + "%stest_ca' % se, None, ['che.py"']),
+        (f2, os_path + 'dirname(abspath(__file__)) + sep + "test_ca', None, ['che.py"']),
+        (f2, os_path + 'join(dirname(__file__), "completion") + sep + "basi', None, ['c.py"']),
+        (f2, os_path + 'join("test", "completion") + sep + "basi', None, ['c.py"']),
+
+        # inside join
+        (f2, os_path + 'join(dirname(__file__), "completion", "basi', None, ['c.py"']),
+        (f2, os_path + 'join(dirname(__file__), "completion", "basi)', 43, ['c.py"']),
+        (f2, os_path + 'join(dirname(__file__), "completion", "basi")', 43, ['c.py']),
+        (f2, os_path + 'join(dirname(__file__), "completion", "basi)', 35, ['']),
+        (f2, os_path + 'join(dirname(__file__), "completion", "basi)', 33, ['on"']),
+        (f2, os_path + 'join(dirname(__file__), "completion", "basi")', 33, ['on"']),
+
+        # join with one argument. join will not get evaluated and the result is
+        # that directories and in a slash. This is unfortunate, but doesn't
+        # really matter.
+        (f2, os_path + 'join("tes', 9, ['t"']),
+        (f2, os_path + 'join(\'tes)', 9, ["t'"]),
+        (f2, os_path + 'join(r"tes"', 10, ['t']),
+        (f2, os_path + 'join("""tes""")', 11, ['t']),
+
+        # Almost like join but not really
+        (f2, os_path + 'join["tes', 9, ['t' + s]),
+        (f2, os_path + 'join["tes"', 9, ['t' + s]),
+        (f2, os_path + 'join["tes"]', 9, ['t' + s]),
+        (f2, os_path + 'join[dirname(__file__), "completi', 33, []),
+        (f2, os_path + 'join[dirname(__file__), "completi"', 33, []),
+        (f2, os_path + 'join[dirname(__file__), "completi"]', 33, []),
+
+        # With full paths
+        (f2, 'import os\nos.path.join(os.path.dirname(__file__), "completi', 49, ['on"']),
+        (f2, 'import os\nos.path.join(os.path.dirname(__file__), "completi"', 49, ['on']),
+        (f2, 'import os\nos.path.join(os.path.dirname(__file__), "completi")', 49, ['on']),
+
+        # With alias
+        (f2, 'import os.path as p as p\np.join(p.dirname(__file__), "completi', None, ['on"']),
+        (f2, 'from os.path import dirname, join as j\nj(dirname(__file__), "completi',
+         None, ['on"']),
+
+        # Trying to break it
+        (f2, os_path + 'join(["tes', 10, ['t' + s]),
+        (f2, os_path + 'join(["tes"]', 10, ['t' + s]),
+        (f2, os_path + 'join(["tes"])', 10, ['t' + s]),
+        (f2, os_path + 'join("test", "test_cac" + x,', 22, ['he.py']),
+    ]
+)
+def test_file_path_completions(Script, file, code, column, expected):
+    line = None
+    if isinstance(column, tuple):
+        line, column = column
+    comps = Script(code, path=file, line=line, column=column).completions()
+    if expected == "A LOT":
+        assert len(comps) > 100  # This is basically global completions.
+    else:
+        assert [c.complete for c in comps] == expected

test/test_api/test_interpreter.py

@@ -7,8 +7,8 @@ import pytest
 
 import jedi
 from jedi._compatibility import is_py3, py_version
-from jedi.evaluate.compiled import mixed
-
+from jedi.evaluate.compiled import mixed, context
+from importlib import import_module
 
 if py_version > 30:
     def exec_(source, global_map):
@@ -197,7 +197,13 @@ def test_getitem_side_effects():
     _assert_interpreter_complete('foo["asdf"].upper', locals(), ['upper'])
 
 
-def test_property_error_oldstyle():
+@pytest.fixture(params=[False, True])
+def allow_descriptor_access_or_not(request, monkeypatch):
+    monkeypatch.setattr(jedi.Interpreter, '_allow_descriptor_getattr_default', request.param)
+    return request.param
+
+
+def test_property_error_oldstyle(allow_descriptor_access_or_not):
     lst = []
     class Foo3:
         @property
@@ -209,11 +215,14 @@ def test_property_error_oldstyle():
     _assert_interpreter_complete('foo.bar', locals(), ['bar'])
     _assert_interpreter_complete('foo.bar.baz', locals(), [])
 
-    # There should not be side effects
-    assert lst == []
+    if allow_descriptor_access_or_not:
+        assert lst == [1, 1]
+    else:
+        # There should not be side effects
+        assert lst == []
 
 
-def test_property_error_newstyle():
+def test_property_error_newstyle(allow_descriptor_access_or_not):
     lst = []
     class Foo3(object):
         @property
@@ -225,10 +234,25 @@ def test_property_error_newstyle():
     _assert_interpreter_complete('foo.bar', locals(), ['bar'])
     _assert_interpreter_complete('foo.bar.baz', locals(), [])
 
-    # There should not be side effects
-    assert lst == []
+    if allow_descriptor_access_or_not:
+        assert lst == [1, 1]
+    else:
+        # There should not be side effects
+        assert lst == []
 
 
+def test_property_content():
+    class Foo3(object):
+        @property
+        def bar(self):
+            return 1
+
+    foo = Foo3()
+    def_, = jedi.Interpreter('foo.bar', [locals()]).goto_definitions()
+    assert def_.name == 'int'
+
+
+@pytest.mark.skipif(sys.version_info[0] == 2, reason="Ignore Python 2, because EOL")
 def test_param_completion():
     def foo(bar):
         pass
@@ -275,6 +299,7 @@ def test_completion_param_annotations():
     assert d.name == 'bytes'
 
 
+@pytest.mark.skipif(sys.version_info[0] == 2, reason="Ignore Python 2, because EOL")
 def test_keyword_argument():
     def f(some_keyword_argument):
         pass
@@ -439,3 +464,44 @@ def test__wrapped__():
     c, = jedi.Interpreter('syslogs_to_df', [locals()]).completions()
     # Apparently the function starts on the line where the decorator starts.
     assert c.line == syslogs_to_df.__wrapped__.__code__.co_firstlineno + 1
+
+
+@pytest.mark.parametrize('module_name', ['sys', 'time'])
+def test_core_module_completes(module_name):
+    module = import_module(module_name)
+    assert jedi.Interpreter(module_name + '.\n', [locals()]).completions()
+
+
+@pytest.mark.skipif(sys.version_info[0] == 2, reason="Ignore Python 2, because EOL")
+@pytest.mark.parametrize(
+    'code, expected, index', [
+        ('a(', ['a', 'b', 'c'], 0),
+        ('b(', ['b', 'c'], 0),
+        # Might or might not be correct, because c is given as a keyword
+        # argument as well, but that is just what inspect.signature returns.
+        ('c(', ['b', 'c'], 0),
+    ]
+)
+def test_partial_signatures(code, expected, index):
+    import functools
+
+    def func(a, b, c):
+        pass
+
+    a = functools.partial(func)
+    b = functools.partial(func, 1)
+    c = functools.partial(func, 1, c=2)
+
+    sig, = jedi.Interpreter(code, [locals()]).call_signatures()
+    assert sig.name == 'partial'
+    assert [p.name for p in sig.params] == expected
+    assert index == sig.index
+
+
+@pytest.mark.skipif(sys.version_info[0] == 2, reason="Ignore Python 2, because EOL")
+def test_type_var():
+    """This was an issue before, see Github #1369"""
+    import typing
+    x = typing.TypeVar('myvar')
+    def_, = jedi.Interpreter('x', [locals()]).goto_definitions()
+    assert def_.name == 'TypeVar'

test/test_api/test_project.py

@@ -1,6 +1,7 @@
 import os
 
-from ..helpers import get_example_dir
+from ..helpers import get_example_dir, set_cwd, root_dir
+from jedi import Interpreter
 
 
 def test_django_default_project(Script):
@@ -13,3 +14,11 @@ def test_django_default_project(Script):
     c, = script.completions()
     assert c.name == "SomeModel"
     assert script._evaluator.project._django is True
+
+
+def test_interpreter_project_path():
+    # Run from anywhere it should be the cwd.
+    dir = os.path.join(root_dir, 'test')
+    with set_cwd(dir):
+        project = Interpreter('', [locals()])._evaluator.project
+        assert project._path == dir

test/test_api/test_signatures.py

@@ -0,0 +1,74 @@
+import sys
+
+import pytest
+
+_tuple_code = 'from typing import Tuple\ndef f(x: Tuple[int]): ...\nf'
+
+
+@pytest.mark.parametrize(
+    'code, expected_params, execute_annotation', [
+        ('def f(x: 1, y): ...\nf', [None, None], True),
+        ('def f(x: 1, y): ...\nf', ['instance int', None], False),
+        ('def f(x: int): ...\nf', ['instance int'], True),
+        ('from typing import List\ndef f(x: List[int]): ...\nf', ['instance list'], True),
+        ('from typing import List\ndef f(x: List[int]): ...\nf', ['class list'], False),
+        (_tuple_code, ['Tuple: _SpecialForm = ...'], True),
+        (_tuple_code, ['Tuple: _SpecialForm = ...'], False),
+        ('x=str\ndef f(p: x): ...\nx=int\nf', ['instance int'], True),
+
+        ('def f(*args, **kwargs): ...\nf', [None, None], False),
+        ('def f(*args: int, **kwargs: str): ...\nf', ['class int', 'class str'], False),
+    ]
+)
+def test_param_annotation(Script, code, expected_params, execute_annotation, skip_python2):
+    func, = Script(code).goto_assignments()
+    sig, = func.get_signatures()
+    for p, expected in zip(sig.params, expected_params):
+        annotations = p.infer_annotation(execute_annotation=execute_annotation)
+        if expected is None:
+            assert not annotations
+        else:
+            annotation, = annotations
+            assert annotation.description == expected
+
+
+@pytest.mark.parametrize(
+    'code, expected_params', [
+        ('def f(x=1, y=int, z): pass\nf', ['instance int', 'class int', None]),
+        ('def f(*args, **kwargs): pass\nf', [None, None]),
+        ('x=1\ndef f(p=x): pass\nx=""\nf', ['instance int']),
+    ]
+)
+def test_param_default(Script, code, expected_params):
+    func, = Script(code).goto_assignments()
+    sig, = func.get_signatures()
+    for p, expected in zip(sig.params, expected_params):
+        annotations = p.infer_default()
+        if expected is None:
+            assert not annotations
+        else:
+            annotation, = annotations
+            assert annotation.description == expected
+
+
+@pytest.mark.skipif(sys.version_info < (3, 5), reason="Python <3.5 doesn't support __signature__")
+@pytest.mark.parametrize(
+    'code, index, param_code, kind', [
+        ('def f(x=1): pass\nf', 0, 'x=1', 'POSITIONAL_OR_KEYWORD'),
+        ('def f(*args:int): pass\nf', 0, '*args: int', 'VAR_POSITIONAL'),
+        ('def f(**kwargs: List[x]): pass\nf', 0, '**kwargs: List[x]', 'VAR_KEYWORD'),
+        ('def f(*, x:int=5): pass\nf', 0, 'x: int=5', 'KEYWORD_ONLY'),
+        ('def f(*args, x): pass\nf', 1, 'x', 'KEYWORD_ONLY'),
+    ]
+)
+def test_param_kind_and_name(code, index, param_code, kind, Script, skip_python2):
+    func, = Script(code).goto_assignments()
+    sig, = func.get_signatures()
+    param = sig.params[index]
+    assert param.to_string() == param_code
+    assert param.kind.name == kind
+
+
+def test_staticmethod(Script):
+    s, = Script('staticmethod(').call_signatures()
+    assert s.to_string() == 'staticmethod(f: Callable)'

test/test_evaluate/test_context.py

@@ -1,3 +1,6 @@
+from jedi._compatibility import force_unicode
+
+
 def test_module_attributes(Script):
     def_, = Script('__name__').completions()
     assert def_.name == '__name__'
@@ -5,3 +8,14 @@ def test_module_attributes(Script):
     assert def_.column is None
     str_, = def_.infer()
     assert str_.name == 'str'
+
+
+def test_module__file__(Script, environment):
+    assert not Script('__file__').goto_definitions()
+    def_, = Script('__file__', path='example.py').goto_definitions()
+    value = force_unicode(def_._name._context.get_safe_value())
+    assert value.endswith('example.py')
+
+    def_, = Script('import antigravity; antigravity.__file__').goto_definitions()
+    value = force_unicode(def_._name._context.get_safe_value())
+    assert value.endswith('.py')

test/test_evaluate/test_docstring.py

@@ -6,6 +6,7 @@ from textwrap import dedent
 import jedi
 import pytest
 from ..helpers import unittest
+import sys
 
 try:
     import numpydoc  # NOQA
@@ -21,6 +22,11 @@ except ImportError:
 else:
     numpy_unavailable = False
 
+if sys.version_info.major == 2:
+    # In Python 2 there's an issue with tox/docutils that makes the tests fail,
+    # Python 2 is soon end-of-life, so just don't support numpydoc for it anymore.
+    numpydoc_unavailable = True
+
 
 def test_function_doc(Script):
     defs = Script("""
@@ -385,3 +391,26 @@ def test_numpy_comp_returns():
     )
     names = [c.name for c in jedi.Script(s).completions()]
     assert 'diagonal' in names
+
+
+def test_decorator(Script):
+    code = dedent('''
+        def decorator(name=None):
+            def _decorate(func):
+                @wraps(func)
+                def wrapper(*args, **kwargs):
+                    """wrapper docstring"""
+                    return func(*args, **kwargs)
+                return wrapper
+            return _decorate
+
+
+        @decorator('testing')
+        def check_user(f):
+            """Nice docstring"""
+            pass
+
+        check_user''')
+
+    d, = Script(code).goto_definitions()
+    assert d.docstring(raw=True) == 'Nice docstring'

test/test_evaluate/test_imports.py

@@ -472,6 +472,6 @@ def test_relative_import_star(Script):
     from . import *
     furl.c
     """
-    script = jedi.Script(source,3,len("furl.c"), 'export.py')
+    script = jedi.Script(source, 3, len("furl.c"), 'export.py')
 
     assert script.completions()

test/test_evaluate/test_signature.py

@@ -1,5 +1,8 @@
-import pytest
+from textwrap import dedent
 from operator import ge, lt
+import re
+
+import pytest
 
 from jedi.evaluate.gradual.conversion import _stub_to_python_context_set
 
@@ -34,6 +37,31 @@ def test_compiled_signature(Script, environment, code, sig, names, op, version):
     assert [n.string_name for n in signature.get_param_names()] == names
 
 
+classmethod_code = '''
+class X:
+    @classmethod
+    def x(cls, a, b):
+        pass
+
+    @staticmethod
+    def static(a, b):
+        pass
+'''
+
+
+partial_code = '''
+import functools
+
+def func(a, b, c):
+    pass
+
+a = functools.partial(func)
+b = functools.partial(func, 1)
+c = functools.partial(func, 1, c=2)
+d = functools.partial()
+'''
+
+
 @pytest.mark.parametrize(
     'code, expected', [
         ('def f(a, * args, x): pass\n f(', 'f(a, *args, x)'),
@@ -41,6 +69,16 @@ def test_compiled_signature(Script, environment, code, sig, names, op, version):
         ('def f(*, x= 3,**kwargs): pass\n f(', 'f(*, x=3, **kwargs)'),
         ('def f(x,/,y,* ,z): pass\n f(', 'f(x, /, y, *, z)'),
         ('def f(a, /, *, x=3, **kwargs): pass\n f(', 'f(a, /, *, x=3, **kwargs)'),
+
+        (classmethod_code + 'X.x(', 'x(cls, a, b)'),
+        (classmethod_code + 'X().x(', 'x(cls, a, b)'),
+        (classmethod_code + 'X.static(', 'static(a, b)'),
+        (classmethod_code + 'X().static(', 'static(a, b)'),
+
+        (partial_code + 'a(', 'func(a, b, c)'),
+        (partial_code + 'b(', 'func(b, c)'),
+        (partial_code + 'c(', 'func(b)'),
+        (partial_code + 'd(', None),
     ]
 )
 def test_tree_signature(Script, environment, code, expected):
@@ -48,15 +86,183 @@ def test_tree_signature(Script, environment, code, expected):
     if environment.version_info < (3, 8):
         pytest.skip()
 
+    if expected is None:
+        assert not Script(code).call_signatures()
+    else:
+        sig, = Script(code).call_signatures()
+        assert expected == sig.to_string()
+
+
+@pytest.mark.parametrize(
+    'combination, expected', [
+        # Functions
+        ('full_redirect(simple)', 'b, *, c'),
+        ('full_redirect(simple4)', 'b, x: int'),
+        ('full_redirect(a)', 'b, *args'),
+        ('full_redirect(kw)', 'b, *, c, **kwargs'),
+        ('full_redirect(akw)', 'c, *args, **kwargs'),
+
+        # Non functions
+        ('full_redirect(lambda x, y: ...)', 'y'),
+        ('full_redirect()', '*args, **kwargs'),
+        ('full_redirect(1)', '*args, **kwargs'),
+
+        # Classes / inheritance
+        ('full_redirect(C)', 'z, *, c'),
+        ('full_redirect(C())', 'y'),
+        ('D', 'D(a, z, /)'),
+        ('D()', 'D(x, y)'),
+        ('D().foo', 'foo(a, *, bar, z, **kwargs)'),
+
+        # Merging
+        ('two_redirects(simple, simple)', 'a, b, *, c'),
+        ('two_redirects(simple2, simple2)', 'x'),
+        ('two_redirects(akw, kw)', 'a, c, *args, **kwargs'),
+        ('two_redirects(kw, akw)', 'a, b, *args, c, **kwargs'),
+
+        ('combined_redirect(simple, simple2)', 'a, b, /, *, x'),
+        ('combined_redirect(simple, simple3)', 'a, b, /, *, a, x: int'),
+        ('combined_redirect(simple2, simple)', 'x, /, *, a, b, c'),
+        ('combined_redirect(simple3, simple)', 'a, x: int, /, *, a, b, c'),
+
+        ('combined_redirect(simple, kw)', 'a, b, /, *, a, b, c, **kwargs'),
+        ('combined_redirect(kw, simple)', 'a, b, /, *, a, b, c'),
+
+        ('combined_lot_of_args(kw, simple4)', '*, b'),
+        ('combined_lot_of_args(simple4, kw)', '*, b, c, **kwargs'),
+
+        ('combined_redirect(combined_redirect(simple2, simple4), combined_redirect(kw, simple5))',
+         'x, /, *, y'),
+        ('combined_redirect(combined_redirect(simple4, simple2), combined_redirect(simple5, kw))',
+         'a, b, x: int, /, *, a, b, c, **kwargs'),
+        ('combined_redirect(combined_redirect(a, kw), combined_redirect(kw, simple5))',
+         'a, b, /, *args, y'),
+
+        ('no_redirect(kw)', '*args, **kwargs'),
+        ('no_redirect(akw)', '*args, **kwargs'),
+        ('no_redirect(simple)', '*args, **kwargs'),
+    ]
+)
+def test_nested_signatures(Script, environment, combination, expected, skip_pre_python35):
+    code = dedent('''
+        def simple(a, b, *, c): ...
+        def simple2(x): ...
+        def simple3(a, x: int): ...
+        def simple4(a, b, x: int): ...
+        def simple5(y): ...
+        def a(a, b, *args): ...
+        def kw(a, b, *, c, **kwargs): ...
+        def akw(a, c, *args, **kwargs): ...
+
+        def no_redirect(func):
+            return lambda *args, **kwargs: func(1)
+        def full_redirect(func):
+            return lambda *args, **kwargs: func(1, *args, **kwargs)
+        def two_redirects(func1, func2):
+            return lambda *args, **kwargs: func1(*args, **kwargs) + func2(1, *args, **kwargs)
+        def combined_redirect(func1, func2):
+            return lambda *args, **kwargs: func1(*args) + func2(**kwargs)
+        def combined_lot_of_args(func1, func2):
+            return lambda *args, **kwargs: func1(1, 2, 3, 4, *args) + func2(a=3, x=1, y=1, **kwargs)
+
+        class C:
+            def __init__(self, a, z, *, c): ...
+            def __call__(self, x, y): ...
+
+            def foo(self, bar, z, **kwargs): ...
+
+        class D(C):
+            def __init__(self, *args):
+                super().__init__(*args)
+
+            def foo(self, a, **kwargs):
+                super().foo(**kwargs)
+    ''')
+    code += 'z = ' + combination + '\nz('
     sig, = Script(code).call_signatures()
-    assert expected == sig._signature.to_string()
+    computed = sig.to_string()
+    if not re.match(r'\w+\(', expected):
+        expected = '<lambda>(' + expected + ')'
+    assert expected == computed
 
 
 def test_pow_signature(Script):
     # See github #1357
     sigs = Script('pow(').call_signatures()
-    strings = {sig._signature.to_string() for sig in sigs}
+    strings = {sig.to_string() for sig in sigs}
     assert strings == {'pow(x: float, y: float, z: float, /) -> float',
                        'pow(x: float, y: float, /) -> float',
                        'pow(x: int, y: int, z: int, /) -> Any',
                        'pow(x: int, y: int, /) -> Any'}
+
+
+@pytest.mark.parametrize(
+    'code, signature', [
+        [dedent('''
+            import functools
+            def f(x):
+                pass
+            def x(f):
+                @functools.wraps(f)
+                def wrapper(*args):
+                    # Have no arguments here, but because of wraps, the signature
+                    # should still be f's.
+                    return f(*args)
+                return wrapper
+
+            x(f)('''), 'f(x, /)'],
+        [dedent('''
+            import functools
+            def f(x):
+                pass
+            def x(f):
+                @functools.wraps(f)
+                def wrapper():
+                    # Have no arguments here, but because of wraps, the signature
+                    # should still be f's.
+                    return 1
+                return wrapper
+
+            x(f)('''), 'f()'],
+    ]
+)
+def test_wraps_signature(Script, code, signature, skip_pre_python35):
+    sigs = Script(code).call_signatures()
+    assert {sig.to_string() for sig in sigs} == {signature}
+
+
+@pytest.mark.parametrize(
+    'start, start_params', [
+        ['@dataclass\nclass X:', []],
+        ['@dataclass(eq=True)\nclass X:', []],
+        [dedent('''
+         class Y():
+             y: int
+         @dataclass
+         class X(Y):'''), []],
+        [dedent('''
+         @dataclass
+         class Y():
+             y: int
+             z = 5
+         @dataclass
+         class X(Y):'''), ['y']],
+    ]
+)
+def test_dataclass_signature(Script, skip_pre_python37, start, start_params):
+    code = dedent('''
+            name: str
+            foo = 3
+            price: float
+            quantity: int = 0.0
+
+        X(''')
+
+    code = 'from dataclasses import dataclass\n' + start + code
+
+    sig, = Script(code).call_signatures()
+    assert [p.name for p in sig.params] == start_params + ['name', 'price', 'quantity']
+    quantity, = sig.params[-1].infer()
+    assert quantity.name == 'int'
+    price, = sig.params[-2].infer()
+    assert price.name == 'float'