Feat: Implement TooManyRaisesViolation rule and config. Issue #14

adrwes · Feb 24, 2020 · 6524c7d · 6524c7d
1 parent 2c634e1
commit 6524c7d
Show file tree

Hide file tree

Showing 6 changed files with 31 additions and 3 deletions.
diff --git a/wemake_python_styleguide/options/config.py b/wemake_python_styleguide/options/config.py
@@ -121,6 +121,9 @@
 - ``max-attributes`` - maximum number of public instance attributes,
     defaults to
     :str:`wemake_python_styleguide.options.defaults.MAX_ATTRIBUTES`
+- ``max-raises`` - maximum number of raises in a function,
+    defaults to
+    :str:`wemake_python_styleguide.options.defaults.MAX_RAISES`
 - ``max-cognitive-score`` - maximum amount of cognitive complexity
     per function, defaults to
     :str:`wemake_python_styleguide.options.defaults.MAX_COGNITIVE_SCORE`
@@ -360,6 +363,12 @@ class Configuration(object):
             'Maximum number of public instance attributes.',
         ),
 
+        _Option(
+            '--max-raises',
+            defaults.MAX_RAISES,
+            'Maximum number of raises in a function.',
+        ),
+
         _Option(
             '--max-cognitive-score',
             defaults.MAX_COGNITIVE_SCORE,

diff --git a/wemake_python_styleguide/options/defaults.py b/wemake_python_styleguide/options/defaults.py
@@ -109,6 +109,9 @@
 #: Maximum number of public attributes in a single class.
 MAX_ATTRIBUTES: Final = 6  # guessed
 
+#: Maximum number of raises in a function.
+MAX_RAISES: Final = 3  # guessed
+
 #: Maximum amount of cognitive complexity per function.
 MAX_COGNITIVE_SCORE: Final = 12  # based on this code statistics
 

diff --git a/wemake_python_styleguide/options/validation.py b/wemake_python_styleguide/options/validation.py
@@ -89,6 +89,7 @@ class _ValidatedOptions(object):
     max_asserts: int = attr.ib(validator=[_min_max(min=1)])
     max_access_level: int = attr.ib(validator=[_min_max(min=1)])
     max_attributes: int = attr.ib(validator=[_min_max(min=1)])
+    max_raises: int = attr.ib(validator=[_min_max(min=1)])
     max_cognitive_score: int = attr.ib(validator=[_min_max(min=1)])
     max_cognitive_average: int = attr.ib(validator=[_min_max(min=1)])
     max_call_level: int = attr.ib(validator=[_min_max(min=1)])

diff --git a/wemake_python_styleguide/types.py b/wemake_python_styleguide/types.py
@@ -210,6 +210,10 @@ def max_access_level(self) -> int:
     def max_attributes(self) -> int:
         ...
 
+    @property
+    def max_raises(self) -> int:
+        ...
+
     @property
     def max_cognitive_score(self) -> int:
         ...

diff --git a/wemake_python_styleguide/violations/complexity.py b/wemake_python_styleguide/violations/complexity.py
@@ -1110,14 +1110,16 @@ class TooManyRaisesViolation(ASTViolation):
         Solution here.
 
     Configuration:
-        Configuration here.
+        This rule is configurable with ``--max-raises``.
+        Default:
+        :str:`wemake_python_styleguide.options.defaults.MAX_RAISES`
 
     See also:
         Links here.
 
-    .. versionadded:: 0.14.0
+    .. versionadded:: 0.15.0
 
     """
 
-    error_template = 'Error template here'
+    error_template = 'Found too many raises in a function: {0}'
     code = 235
diff --git a/wemake_python_styleguide/visitors/ast/complexity/function.py b/wemake_python_styleguide/visitors/ast/complexity/function.py
@@ -25,6 +25,7 @@
     TooManyExpressionsViolation,
     TooManyLocalsViolation,
     TooManyReturnsViolation,
+    TooManyRaisesViolation,
 )
 from wemake_python_styleguide.visitors.base import BaseNodeVisitor
 from wemake_python_styleguide.visitors.decorators import alias
@@ -53,6 +54,7 @@ def __init__(self) -> None:
         self.asserts: _FunctionCounter = defaultdict(int)
         self.returns: _FunctionCounter = defaultdict(int)
         self.expressions: _FunctionCounter = defaultdict(int)
+        self.raises: _FunctionCounter = defaultdict(int)
         self.variables: DefaultDict[AnyFunctionDef, List[str]] = defaultdict(
             list,
         )
@@ -106,6 +108,7 @@ def _check_sub_node(
             ast.Expr: self.expressions,
             ast.Await: self.awaits,
             ast.Assert: self.asserts,
+            ast.Raise: self.raises,
         }
 
         for types, counter in error_counters.items():
@@ -146,6 +149,7 @@ def visit_any_function(self, node: AnyFunctionDef) -> None:
             TooManyLocalsViolation
             TooManyArgumentsViolation
             TooManyAwaitsViolation
+            TooManyRaisesViolation
 
         """
         self._counter.check_arguments_count(node)
@@ -214,6 +218,11 @@ def _function_checks(self) -> List[_CheckRule]:
                 self.options.max_asserts,
                 TooManyAssertsViolation,
             ),
+            (
+                self._counter.raises,
+                self.options.max_raises,
+                TooManyRaisesViolation,
+            ),
         ]
 
     def _post_visit(self) -> None: