Merge pull request #1885 from asford/attrs_support

Extend dataclass constructor hinting to attrs next-gen apis.

CHANGELOG.rst

@@ -6,6 +6,8 @@ Changelog
 Unreleased
 ++++++++++
 
+- Added dataclass-equivalent for attrs.define
+
 0.18.1 (2021-11-17)
 +++++++++++++++++++
 

jedi/plugins/stdlib.py

@@ -803,6 +803,15 @@ _implemented = {
         # For now this works at least better than Jedi trying to understand it.
         'dataclass': _dataclass
     },
+    # attrs exposes declaration interface roughly compatible with dataclasses
+    # via attrs.define, attrs.frozen and attrs.mutable
+    # https://www.attrs.org/en/stable/names.html
+    'attr': {
+        'define': _dataclass,
+    },
+    'attrs': {
+        'define': _dataclass,
+    },
     'os.path': {
         'dirname': _create_string_input_function(os.path.dirname),
         'abspath': _create_string_input_function(os.path.abspath),

setup.py

@@ -41,6 +41,7 @@ setup(name='jedi',
               # coloroma for colored debug output
               'colorama',
               'Django<3.1',  # For now pin this.
+              'attrs',
           ],
           'qa': [
               'flake8==3.8.3',

test/test_inference/test_signature.py

@@ -355,6 +355,48 @@ def test_dataclass_signature(Script, skip_pre_python37, start, start_params):
     price, = sig.params[-2].infer()
     assert price.name == 'float'
 
+@pytest.mark.parametrize(
+    'start, start_params', [
+        ['@define\nclass X:', []],
+        ['@frozen\nclass X:', []],
+        ['@define(eq=True)\nclass X:', []],
+        [dedent('''
+         class Y():
+             y: int
+         @define
+         class X(Y):'''), []],
+        [dedent('''
+         @define
+         class Y():
+             y: int
+             z = 5
+         @define
+         class X(Y):'''), ['y']],
+    ]
+)
+def test_attrs_signature(Script, skip_pre_python37, start, start_params):
+    has_attrs = bool(Script('import attrs').infer())
+    if not has_attrs:
+        raise pytest.skip("attrs needed in target environment to run this test")
+
+    code = dedent('''
+            name: str
+            foo = 3
+            price: float
+            quantity: int = 0.0
+
+        X(''')
+
+    # attrs exposes two namespaces
+    code = 'from attrs import define, frozen\n' + start + code
+
+    sig, = Script(code).get_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'
+
 
 @pytest.mark.parametrize(
     'stmt, expected', [