Allow for hanging indent when documenting args in Google style (#564)

Co-authored-by: Ryan Morshead <[email protected]>
Co-authored-by: Sambhav Kothari <[email protected]>

docs/release_notes.rst

@@ -10,6 +10,7 @@ Current Development Version
 
 New Features
 
+* Allow for hanging indent when documenting args in Google style. (#449)
 * Add support for `property_decorators` config to ignore D401.
 * Add support for Python 3.10 (#554).
 * Replace D10X errors with D419 if docstring exists but is empty (#559).

src/pydocstyle/checker.py

@@ -6,6 +6,7 @@
 from collections import namedtuple
 from itertools import chain, takewhile
 from re import compile as re
+from textwrap import dedent
 
 from . import violations
 from .config import IllegalConfiguration
@@ -122,6 +123,8 @@ class ConventionChecker:
         r"\s*"
         # Followed by a colon
         r":"
+        # Might have a new line and leading whitespace
+        r"\n?\s*"
         # Followed by 1 or more characters - which is the docstring for the parameter
         ".+"
     )
@@ -843,10 +846,38 @@ def _check_args_section(docstring, definition, context):
             * The section documents all function arguments (D417)
                 except `self` or `cls` if it is a method.
 
+        Documentation for each arg should start at the same indentation
+        level. For example, in this case x and y are distinguishable::
+
+            Args:
+                x: Lorem ipsum dolor sit amet
+                y: Ut enim ad minim veniam
+
+        In the case below, we only recognize x as a documented parameter
+        because the rest of the content is indented as if it belongs
+        to the description for x::
+
+            Args:
+                x: Lorem ipsum dolor sit amet
+                    y: Ut enim ad minim veniam
         """
         docstring_args = set()
-        for line in context.following_lines:
-            match = ConventionChecker.GOOGLE_ARGS_REGEX.match(line)
+        # normalize leading whitespace
+        args_content = dedent("\n".join(context.following_lines)).strip()
+
+        args_sections = []
+        for line in args_content.splitlines(keepends=True):
+            if not line[:1].isspace():
+                # This line is the start of documentation for the next
+                # parameter because it doesn't start with any whitespace.
+                args_sections.append(line)
+            else:
+                # This is a continuation of documentation for the last
+                # parameter because it does start with whitespace.
+                args_sections[-1] += line
+
+        for section in args_sections:
+            match = ConventionChecker.GOOGLE_ARGS_REGEX.match(section)
             if match:
                 docstring_args.add(match.group(1))
         yield from ConventionChecker._check_missing_args(

src/tests/test_cases/sections.py

@@ -367,10 +367,7 @@ def test_missing_docstring(a, b):  # noqa: D213, D407
         """
 
     @staticmethod
-    @expect("D417: Missing argument descriptions in the docstring "
-            "(argument(s) skip, verbose are missing descriptions in "
-            "'test_missing_docstring_another' docstring)", arg_count=2)
-    def test_missing_docstring_another(skip, verbose):  # noqa: D213, D407
+    def test_hanging_indent(skip, verbose):  # noqa: D213, D407
         """Do stuff.
 
         Args: