fix: correctly handle variables declaration (#685)

incendial · web-flow · commit f81d54a867bc · 2022-02-07T21:53:36.000+03:00
* fix: correctly handle variables declaration

* fix: ignore a class usage inside State&lt;T&gt; for check-unused-code command

* chore: update test matcher
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -2,6 +2,8 @@
 
 ## Unreleased
 
+* fix: ignore a class usage inside `State<T>` for `check-unused-code` command.
+* fix: correctly handle variables declaration for `check-unused-code` command.
 * feat: add static code diagnostics `avoid-dynamic`, `prefer-async-await`.
 
 ## 4.10.1
diff --git a/lib/src/analyzers/lint_analyzer/anti_patterns/anti_patterns_list/long_method.dart b/lib/src/analyzers/lint_analyzer/anti_patterns/anti_patterns_list/long_method.dart
@@ -3,6 +3,7 @@
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/element/type.dart';
 
+import '../../../../utils/flutter_types_utils.dart';
 import '../../../../utils/node_utils.dart';
 import '../../lint_utils.dart';
 import '../../metrics/metric_utils.dart';
@@ -15,7 +16,6 @@ import '../../models/report.dart';
 import '../../models/scoped_class_declaration.dart';
 import '../../models/scoped_function_declaration.dart';
 import '../../models/severity.dart';
-import '../../rules/flutter_rule_utils.dart';
 import '../models/pattern.dart';
 import '../pattern_utils.dart';
 
diff --git a/lib/src/analyzers/lint_analyzer/rules/rules_list/always_remove_listener/always_remove_listener_rule.dart b/lib/src/analyzers/lint_analyzer/rules/rules_list/always_remove_listener/always_remove_listener_rule.dart
@@ -6,12 +6,12 @@ import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:collection/collection.dart';
 
+import '../../../../../utils/flutter_types_utils.dart';
 import '../../../../../utils/node_utils.dart';
 import '../../../lint_utils.dart';
 import '../../../models/internal_resolved_unit_result.dart';
 import '../../../models/issue.dart';
 import '../../../models/severity.dart';
-import '../../flutter_rule_utils.dart';
 import '../../models/flutter_rule.dart';
 import '../../rule_utils.dart';
 
diff --git a/lib/src/analyzers/lint_analyzer/rules/rules_list/avoid_returning_widgets/avoid_returning_widgets_rule.dart b/lib/src/analyzers/lint_analyzer/rules/rules_list/avoid_returning_widgets/avoid_returning_widgets_rule.dart
@@ -4,12 +4,12 @@ import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
 
+import '../../../../../utils/flutter_types_utils.dart';
 import '../../../../../utils/node_utils.dart';
 import '../../../lint_utils.dart';
 import '../../../models/internal_resolved_unit_result.dart';
 import '../../../models/issue.dart';
 import '../../../models/severity.dart';
-import '../../flutter_rule_utils.dart';
 import '../../models/flutter_rule.dart';
 import '../../rule_utils.dart';
 
diff --git a/lib/src/analyzers/lint_analyzer/rules/rules_list/avoid_unnecessary_setstate/avoid_unnecessary_setstate_rule.dart b/lib/src/analyzers/lint_analyzer/rules/rules_list/avoid_unnecessary_setstate/avoid_unnecessary_setstate_rule.dart
@@ -3,12 +3,12 @@
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
 
+import '../../../../../utils/flutter_types_utils.dart';
 import '../../../../../utils/node_utils.dart';
 import '../../../lint_utils.dart';
 import '../../../models/internal_resolved_unit_result.dart';
 import '../../../models/issue.dart';
 import '../../../models/severity.dart';
-import '../../flutter_rule_utils.dart';
 import '../../models/flutter_rule.dart';
 import '../../rule_utils.dart';
 
diff --git a/lib/src/analyzers/lint_analyzer/rules/rules_list/avoid_unnecessary_type_assertions/avoid_unnecessary_type_assertions_rule.dart b/lib/src/analyzers/lint_analyzer/rules/rules_list/avoid_unnecessary_type_assertions/avoid_unnecessary_type_assertions_rule.dart
@@ -4,12 +4,12 @@ import 'package:analyzer/dart/element/nullability_suffix.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:collection/collection.dart';
 
+import '../../../../../utils/dart_types_utils.dart';
 import '../../../../../utils/node_utils.dart';
 import '../../../lint_utils.dart';
 import '../../../models/internal_resolved_unit_result.dart';
 import '../../../models/issue.dart';
 import '../../../models/severity.dart';
-import '../../dart_rule_utils.dart';
 import '../../models/common_rule.dart';
 import '../../rule_utils.dart';
 
diff --git a/lib/src/analyzers/lint_analyzer/rules/rules_list/avoid_wrapping_in_padding/avoid_wrapping_in_padding_rule.dart b/lib/src/analyzers/lint_analyzer/rules/rules_list/avoid_wrapping_in_padding/avoid_wrapping_in_padding_rule.dart
@@ -5,12 +5,12 @@ import 'package:analyzer/dart/ast/visitor.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:collection/collection.dart';
 
+import '../../../../../utils/flutter_types_utils.dart';
 import '../../../../../utils/node_utils.dart';
 import '../../../lint_utils.dart';
 import '../../../models/internal_resolved_unit_result.dart';
 import '../../../models/issue.dart';
 import '../../../models/severity.dart';
-import '../../flutter_rule_utils.dart';
 import '../../models/flutter_rule.dart';
 import '../../rule_utils.dart';
 
diff --git a/lib/src/analyzers/lint_analyzer/rules/rules_list/prefer_extracting_callbacks/prefer_extracting_callbacks_rule.dart b/lib/src/analyzers/lint_analyzer/rules/rules_list/prefer_extracting_callbacks/prefer_extracting_callbacks_rule.dart
@@ -3,12 +3,12 @@
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
 
+import '../../../../../utils/flutter_types_utils.dart';
 import '../../../../../utils/node_utils.dart';
 import '../../../lint_utils.dart';
 import '../../../models/internal_resolved_unit_result.dart';
 import '../../../models/issue.dart';
 import '../../../models/severity.dart';
-import '../../flutter_rule_utils.dart';
 import '../../models/flutter_rule.dart';
 import '../../rule_utils.dart';
 
diff --git a/lib/src/analyzers/lint_analyzer/rules/rules_list/prefer_first/prefer_first_rule.dart b/lib/src/analyzers/lint_analyzer/rules/rules_list/prefer_first/prefer_first_rule.dart
@@ -3,13 +3,13 @@
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
 
+import '../../../../../utils/dart_types_utils.dart';
 import '../../../../../utils/node_utils.dart';
 import '../../../lint_utils.dart';
 import '../../../models/internal_resolved_unit_result.dart';
 import '../../../models/issue.dart';
 import '../../../models/replacement.dart';
 import '../../../models/severity.dart';
-import '../../dart_rule_utils.dart';
 import '../../models/common_rule.dart';
 import '../../rule_utils.dart';
 
diff --git a/lib/src/analyzers/lint_analyzer/rules/rules_list/prefer_last/prefer_last_rule.dart b/lib/src/analyzers/lint_analyzer/rules/rules_list/prefer_last/prefer_last_rule.dart
@@ -4,13 +4,13 @@ import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
 
+import '../../../../../utils/dart_types_utils.dart';
 import '../../../../../utils/node_utils.dart';
 import '../../../lint_utils.dart';
 import '../../../models/internal_resolved_unit_result.dart';
 import '../../../models/issue.dart';
 import '../../../models/replacement.dart';
 import '../../../models/severity.dart';
-import '../../dart_rule_utils.dart';
 import '../../models/common_rule.dart';
 import '../../rule_utils.dart';
 
diff --git a/lib/src/analyzers/lint_analyzer/rules/rules_list/prefer_single_widget_per_file/prefer_single_widget_per_file_rule.dart b/lib/src/analyzers/lint_analyzer/rules/rules_list/prefer_single_widget_per_file/prefer_single_widget_per_file_rule.dart
@@ -3,12 +3,12 @@
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
 
+import '../../../../../utils/flutter_types_utils.dart';
 import '../../../../../utils/node_utils.dart';
 import '../../../lint_utils.dart';
 import '../../../models/internal_resolved_unit_result.dart';
 import '../../../models/issue.dart';
 import '../../../models/severity.dart';
-import '../../flutter_rule_utils.dart';
 import '../../models/flutter_rule.dart';
 import '../../rule_utils.dart';
 
diff --git a/lib/src/analyzers/unused_code_analyzer/used_code_visitor.dart b/lib/src/analyzers/unused_code_analyzer/used_code_visitor.dart
@@ -4,6 +4,7 @@ import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
 import 'package:analyzer/dart/element/element.dart';
 
+import '../../utils/flutter_types_utils.dart';
 import 'models/file_elements_usage.dart';
 import 'models/prefix_element_usage.dart';
 
@@ -149,7 +150,13 @@ class UsedCodeVisitor extends RecursiveAstVisitor<void> {
     }
 
     // Declarations are not a sign of usage.
-    if (identifier.parent is Declaration) {
+    if (identifier.parent is Declaration &&
+        !_isVariableDeclarationInitializer(identifier.parent, identifier)) {
+      return;
+    }
+
+    // Usage in State<WidgetClassName> is not a sing of usage.
+    if (_isUsedAsNamedTypeForWidgetState(identifier)) {
       return;
     }
 
@@ -202,4 +209,17 @@ class UsedCodeVisitor extends RecursiveAstVisitor<void> {
       return previousValue;
     });
   }
+
+  bool _isVariableDeclarationInitializer(
+    AstNode? target,
+    SimpleIdentifier identifier,
+  ) =>
+      target is VariableDeclaration && target.initializer == identifier;
+
+  bool _isUsedAsNamedTypeForWidgetState(SimpleIdentifier identifier) {
+    final grandGrandParent = identifier.parent?.parent?.parent;
+
+    return grandGrandParent is NamedType &&
+        isWidgetStateOrSubclass(grandGrandParent.type);
+  }
 }
diff --git a/lib/src/utils/dart_types_utils.dart b/lib/src/utils/dart_types_utils.dart
diff --git a/lib/src/utils/flutter_types_utils.dart b/lib/src/utils/flutter_types_utils.dart
diff --git a/test/resources/unused_code_analyzer/public_members.dart b/test/resources/unused_code_analyzer/public_members.dart
@@ -160,3 +160,26 @@ typedef Hello = String;
 
 // LINT
 typedef World = int;
+
+const double _kMenuVerticalPadding = 1;
+
+void setPadding() {
+  const padding = _kMenuVerticalPadding;
+}
+
+// LINT
+class MyOtherWidget extends StatefulWidget {
+  MyOtherWidget();
+
+  @override
+  _MyOtherWidgetState createState() => _MyOtherWidgetState();
+}
+
+class _MyOtherWidgetState extends BaseState<MyOtherWidget> {
+  @override
+  Widget build(BuildContext context) => ElevatedButton(
+        onPressed: () {},
+        onLongPress: () {},
+        child: Text('PRESS'),
+      );
+}
diff --git a/test/resources/unused_code_analyzer/unused_code_example.dart b/test/resources/unused_code_analyzer/unused_code_example.dart
@@ -24,4 +24,6 @@ void main() {
   SomeEnum.hello;
 
   config.calculateResults();
+
+  setPadding();
 }
diff --git a/test/src/analyzers/unused_code_analyzer/unused_code_analyzer_test.dart b/test/src/analyzers/unused_code_analyzer/unused_code_analyzer_test.dart
@@ -89,7 +89,7 @@ void main() {
             (report) => report.path.endsWith('public_members.dart'),
           );
 
-          expect(report.issues.length, 7);
+          expect(report.issues, hasLength(8));
 
           final firstIssue = report.issues.first;
           expect(firstIssue.declarationName, 'printInteger');
@@ -132,6 +132,12 @@ void main() {
           expect(seventhIssue.declarationType, 'type alias');
           expect(seventhIssue.location.line, 162);
           expect(seventhIssue.location.column, 1);
+
+          final eightsIssue = report.issues.elementAt(7);
+          expect(eightsIssue.declarationName, 'MyOtherWidget');
+          expect(eightsIssue.declarationType, 'class');
+          expect(eightsIssue.location.line, 171);
+          expect(eightsIssue.location.column, 1);
         });
       });
 
