Fix #4812: autodoc ignores type annotated variables

CHANGES

@@ -22,6 +22,7 @@ Bugs fixed
 * #4789: imgconverter: confused by convert.exe of Windows
 * #4783: On windows, Sphinx crashed when drives of srcdir and outdir are
   different
+* #4812: autodoc ignores type annotated variables
 
 Testing
 --------

sphinx/directives/other.py

@@ -23,7 +23,7 @@ from sphinx.util.nodes import explicit_title_re, set_source_info, \
 
 if False:
     # For type annotation
-    from typing import Any, Dict, List, Tuple  # NOQA
+    from typing import Any, Dict, Generator, List, Tuple  # NOQA
     from sphinx.application import Sphinx  # NOQA
 
 

sphinx/pycode/parser.py

@@ -12,6 +12,7 @@ import ast
 import inspect
 import itertools
 import re
+import sys
 import tokenize
 from token import NAME, NEWLINE, INDENT, DEDENT, NUMBER, OP, STRING
 from tokenize import COMMENT, NL
@@ -27,6 +28,21 @@ indent_re = re.compile(u'^\\s*$')
 emptyline_re = re.compile(u'^\\s*(#.*)?$')
 
 
+if sys.version_info >= (3, 6):
+    ASSIGN_NODES = (ast.Assign, ast.AnnAssign)
+else:
+    ASSIGN_NODES = (ast.Assign)
+
+
+def get_assign_targets(node):
+    # type: (ast.AST) -> List[ast.expr]
+    """Get list of targets from Assign and AnnAssign node."""
+    if isinstance(node, ast.Assign):
+        return node.targets
+    else:
+        return [node.target]  # type: ignore
+
+
 def get_lvar_names(node, self=None):
     # type: (ast.AST, ast.expr) -> List[unicode]
     """Convert assignment-AST to variable names.
@@ -284,7 +300,8 @@ class VariableCommentPicker(ast.NodeVisitor):
         # type: (ast.Assign) -> None
         """Handles Assign node and pick up a variable comment."""
         try:
-            varnames = sum([get_lvar_names(t, self=self.get_self()) for t in node.targets], [])
+            targets = get_assign_targets(node)
+            varnames = sum([get_lvar_names(t, self=self.get_self()) for t in targets], [])
             current_line = self.get_line(node.lineno)
         except TypeError:
             return  # this assignment is not new definition!
@@ -320,12 +337,18 @@ class VariableCommentPicker(ast.NodeVisitor):
         for varname in varnames:
             self.add_entry(varname)
 
+    def visit_AnnAssign(self, node):
+        # type: (ast.AST) -> None
+        """Handles AnnAssign node and pick up a variable comment."""
+        self.visit_Assign(node)  # type: ignore
+
     def visit_Expr(self, node):
         # type: (ast.Expr) -> None
         """Handles Expr node and pick up a comment if string."""
-        if (isinstance(self.previous, ast.Assign) and isinstance(node.value, ast.Str)):
+        if (isinstance(self.previous, ASSIGN_NODES) and isinstance(node.value, ast.Str)):
             try:
-                varnames = get_lvar_names(self.previous.targets[0], self.get_self())
+                targets = get_assign_targets(self.previous)
+                varnames = get_lvar_names(targets[0], self.get_self())
                 for varname in varnames:
                     if isinstance(node.value.s, text_type):
                         docstring = node.value.s

tests/test_pycode_parser.py

@@ -9,6 +9,8 @@
     :license: BSD, see LICENSE for details.
 """
 
+import sys
+
 import pytest
 from six import PY2
 
@@ -94,6 +96,18 @@ def test_comment_picker_location():
                                ('Foo', 'attr3'): 'comment for attr3(3)'}
 
 
+@pytest.mark.skipif(sys.version_info < (3, 6), reason='tests for py36+ syntax')
+def test_annotated_assignment_py36():
+    source = ('a: str = "Sphinx"  #: comment\n'
+              'b: int = 1\n'
+              '"""string on next line"""')
+    parser = Parser(source)
+    parser.parse()
+    assert parser.comments == {('', 'a'): 'comment',
+                               ('', 'b'): 'string on next line'}
+    assert parser.definitions == {}
+
+
 def test_complex_assignment():
     source = ('a = 1 + 1; b = a  #: compound statement\n'
               'c, d = (1, 1)  #: unpack assignment\n'