Move load_module a bit around

jedi/evaluate/utils.py

@@ -2,10 +2,19 @@
 import sys
 import contextlib
 import functools
+import re
+import os
 
 from jedi._compatibility import reraise
 
 
+_sep = os.path.sep
+if os.path.altsep is not None:
+    _sep += os.path.altsep
+_path_re = re.compile('(?:\.[^{0}]+|[{0}]__init__\.py)$'.format(re.escape(_sep)))
+del _sep
+
+
 def to_list(func):
     def wrapper(*args, **kwargs):
         return list(func(*args, **kwargs))
@@ -108,3 +117,38 @@ def indent_block(text, indention='    '):
         text = text[:-1]
     lines = text.split('\n')
     return '\n'.join(map(lambda s: indention + s, lines)) + temp
+
+
+def dotted_from_fs_path(fs_path, sys_path):
+    """
+    Changes `/usr/lib/python3.4/email/utils.py` to `email.utils`.  I.e.
+    compares the path with sys.path and then returns the dotted_path. If the
+    path is not in the sys.path, just returns None.
+    """
+    if os.path.basename(fs_path).startswith('__init__.'):
+        # We are calculating the path. __init__ files are not interesting.
+        fs_path = os.path.dirname(fs_path)
+
+    # prefer
+    #   - UNIX
+    #     /path/to/pythonX.Y/lib-dynload
+    #     /path/to/pythonX.Y/site-packages
+    #   - Windows
+    #     C:\path\to\DLLs
+    #     C:\path\to\Lib\site-packages
+    # over
+    #   - UNIX
+    #     /path/to/pythonX.Y
+    #   - Windows
+    #     C:\path\to\Lib
+    path = ''
+    for s in sys_path:
+        if (fs_path.startswith(s) and len(path) < len(s)):
+            path = s
+
+    # - Window
+    # X:\path\to\lib-dynload/datetime.pyd => datetime
+    module_path = fs_path[len(path):].lstrip(os.path.sep).lstrip('/')
+    # - Window
+    # Replace like X:\path\to\something/foo/bar.py
+    return _path_re.sub('', module_path).replace(os.path.sep, '.').replace('/', '.')