Allow dot and comma to be overused string literals

CHANGELOG.md

@@ -24,6 +24,7 @@ Semantic versioning in our case means:
 - Now `InconsistentYieldViolation` and `InconsistentReturnViolation` are raised
   when `yield` or `return` is used with `None`
   where plain version should be used
+- Dot `'.'` and comma `','` do not count against string literal overuse limit anymore
 
 ### Bugfixes
 

tests/test_visitors/test_ast/test_complexity/test_overuses/test_overused_string.py

@@ -200,20 +200,22 @@ def test_string_type_annotations(
     r'"\t"',
     r'"\n"',
     '""',
+    '","',
+    '"."',
 ])
 @pytest.mark.parametrize('prefix', [
     'b',
     'u',
     '',
 ])
-def test_string_overuse_exceptions(
+def test_common_strings_allowed(
     assert_errors,
     parse_ast_tree,
     default_options,
     prefix,
     string_value,
 ):
-    """Ensures that over-used strings raise violations."""
+    """Ensures that common strings do not count against the overuse limit."""
     snippet = string_actions.format(prefix + string_value)
     tree = parse_ast_tree(snippet)
 

wemake_python_styleguide/violations/complexity.py

@@ -851,12 +851,16 @@ class TooManyExceptCasesViolation(ASTViolation):
 
 @final
 class OverusedStringViolation(MaybeASTViolation):
-    """
-    Forbid the overuse of string constants.
+    r"""
+    Forbid the overuse of string literals.
 
     We allow to use strings without any restrictions as annotations for
     variables, arguments, return values, and class attributes.
 
+    Some common string literals like dot `'.'`, comma `','`, empty string `''`,
+    single space `' '`, new line `'\n'`, `'\r\n'` and tabulator `'\t'`
+    do not count against string literal overuse limit.
+
     Reasoning:
         When some string is used more than several time in your code,
         it probably means that this string is a meaningful constant
@@ -875,7 +879,7 @@ class OverusedStringViolation(MaybeASTViolation):
 
     """
 
-    error_template = 'Found string constant over-use: {0}'
+    error_template = "Found string literal over-use: '{0}'"
     code = 226
 
 

wemake_python_styleguide/visitors/ast/complexity/overuses.py

@@ -36,16 +36,21 @@ class StringOveruseVisitor(base.BaseNodeVisitor):
     Restricts repeated usage of the same string constant.
 
     NB: Some short strings are ignored, as their use is very common and
-    forcing assignment would not make much sense (i.e. newlines or "").
+    forcing assignment would not make much sense (i.e. newlines, "",
+    comma, dot).
     """
 
     _ignored_string_constants: ClassVar[_StringConstants] = frozenset((
         ' ',
+        '.',
+        ',',
         '',
         '\n',
         '\r\n',
         '\t',
         b' ',
+        b'.',
+        b',',
         b'',
         b'\n',
         b'\r\n',