Version 0.6.3, closes #450

CHANGELOG.md

@@ -11,6 +11,13 @@ We used to have incremental versioning before `0.1.0`.
 - Adds `safety` and other dependency checks to CI process
 
 
+## Version 0.6.3
+
+### Bugfixes
+
+- Fixes a [crash](https://github.com/wemake-services/wemake-python-styleguide/issues/450) with `dict`s with just values and no keys
+
+
 ## Version 0.6.2
 
 ### Bugfixes

pyproject.toml

@@ -5,7 +5,7 @@ build-backend = "poetry.masonry.api"
 
 [tool.poetry]
 name = "wemake-python-styleguide"
-version = "0.6.2"
+version = "0.6.3"
 description = "The strictest and most opinionated python linter ever"
 
 license = "MIT"

tests/test_visitors/test_ast/test_statements/test_parameters_indentation/test_collection_indentation.py

@@ -99,6 +99,18 @@
 }
 """
 
+correct_simple_regression450 = """
+was_crashing = {**some_other_dict}
+"""
+
+correct_multiline_regression450 = """
+was_crashing = {
+    **some_other_dict,
+    **some_very_other_dict,
+    **third_dict,
+}
+"""
+
 
 # Wrong:
 
@@ -198,6 +210,13 @@
 }
 """
 
+wrong_regression450 = """
+some_dict = {
+    **one,
+    **two, **three,
+}
+"""
+
 
 @pytest.mark.parametrize('code', [
     correct_multiline_string,
@@ -214,6 +233,10 @@
     correct_next_line_set,
     correct_next_line_tuple,
     correct_nested_collections,
+
+    # Regressions:
+    correct_simple_regression450,
+    correct_multiline_regression450,
 ])
 def test_correct_collection_indentation(
     assert_errors,
@@ -247,6 +270,9 @@ def test_correct_collection_indentation(
     wrong_dict_indentation2,
     wrong_dict_indentation3,
     wrong_dict_indentation4,
+
+    # Regressions:
+    wrong_regression450,
 ])
 def test_wrong_collection_indentation(
     assert_errors,

wemake_python_styleguide/logics/collections.py

@@ -0,0 +1,31 @@
+# -*- coding: utf-8 -*-
+
+import ast
+from typing import List, Sequence
+
+
+def normalize_dict_elements(node: ast.Dict) -> Sequence[ast.AST]:
+    """
+    Normalizes ``dict`` elements and enforces consistent order.
+
+    We had a problem that some ``dict`` objects might not have some keys.
+
+    Example::
+
+        some_dict = {**one, **two}
+
+    This ``dict`` contains two values and zero keys.
+    This function will normalize this structure to use
+    values instead of missing keys.
+
+    See also:
+        https://github.com/wemake-services/wemake-python-styleguide/issues/450
+
+    """
+    elements: List[ast.AST] = []
+    for dict_key, dict_value in zip(node.keys, node.values):
+        if dict_key is None:
+            elements.append(dict_value)
+        else:
+            elements.append(dict_key)
+    return elements

wemake_python_styleguide/visitors/ast/statements.py

@@ -3,6 +3,7 @@
 import ast
 from typing import ClassVar, List, Optional, Sequence, Union
 
+from wemake_python_styleguide.logics.collections import normalize_dict_elements
 from wemake_python_styleguide.logics.functions import get_all_arguments
 from wemake_python_styleguide.logics.nodes import is_doc_string
 from wemake_python_styleguide.types import AnyFunctionDef, AnyNodes, final
@@ -215,7 +216,10 @@ def _check_indentation(
 
     def visit_collection(self, node: AnyCollection) -> None:
         """Checks how collection items indentation."""
-        elements = node.keys if isinstance(node, ast.Dict) else node.elts
+        if isinstance(node, ast.Dict):
+            elements = normalize_dict_elements(node)
+        else:
+            elements = node.elts
         self._check_indentation(node, elements, extra_lines=1)
         self.generic_visit(node)