fix: make check-unused-l10n also cover supertype member calls (#658)

* fix: make  also cover supertype member calls

* chore: review fixes

* chore: analyzer fix

Author: incendial

CHANGELOG.md

@@ -3,6 +3,7 @@
 ## Unreleased
 
 * chore: restrict `analyzer` version to `>=2.4.0 <3.3.0`.
+* fix: make `check-unused-l10n` also cover supertype member calls.
 
 ## 4.10.0-dev.2
 

lib/src/analyzers/unused_l10n_analyzer/unused_l10n_analyzer.dart

@@ -3,6 +3,7 @@ import 'dart:io';
 import 'package:analyzer/dart/analysis/results.dart';
 import 'package:analyzer/dart/analysis/utilities.dart';
 import 'package:analyzer/dart/element/element.dart';
+import 'package:analyzer/dart/element/type.dart';
 // ignore: implementation_imports
 import 'package:analyzer/src/dart/element/element.dart';
 import 'package:path/path.dart';
@@ -128,32 +129,27 @@ class UnusedL10nAnalyzer {
     final unusedLocalizationIssues = <UnusedL10nFileReport>[];
 
     localizationUsages.forEach((classElement, usages) {
-      final unit = classElement.thisOrAncestorOfType<CompilationUnitElement>();
-      if (unit != null) {
-        final lineInfo = unit.lineInfo;
-        if (lineInfo != null) {
-          final accessorSourceSpans =
-              _getUnusedAccessors(classElement, usages, unit);
-          final methodSourceSpans =
-              _getUnusedMethods(classElement, usages, unit);
-
-          final filePath = unit.source.toString();
-          final relativePath = relative(filePath, from: rootFolder);
-
-          final issues = [
-            ...accessorSourceSpans,
-            ...methodSourceSpans,
-          ];
-
-          if (issues.isNotEmpty) {
-            unusedLocalizationIssues.add(
-              UnusedL10nFileReport(
-                path: filePath,
-                relativePath: relativePath,
-                className: classElement.name,
-                issues: issues,
-              ),
-            );
+      final report = _getUnusedReports(
+        classElement,
+        usages,
+        rootFolder,
+      );
+      if (report != null) {
+        unusedLocalizationIssues.add(report);
+      }
+
+      final hasCustomSupertype = classElement.allSupertypes.length > 1;
+      if (hasCustomSupertype) {
+        final supertype = classElement.supertype;
+        if (supertype is InterfaceType) {
+          final report = _getUnusedReports(
+            supertype.element,
+            usages,
+            rootFolder,
+            overriddenClassName: classElement.name,
+          );
+          if (report != null) {
+            unusedLocalizationIssues.add(report);
           }
         }
       }
@@ -162,6 +158,45 @@ class UnusedL10nAnalyzer {
     return unusedLocalizationIssues;
   }
 
+  UnusedL10nFileReport? _getUnusedReports(
+    ClassElement classElement,
+    Iterable<String> usages,
+    String rootFolder, {
+    String? overriddenClassName,
+  }) {
+    final unit = classElement.thisOrAncestorOfType<CompilationUnitElement>();
+    if (unit == null) {
+      return null;
+    }
+
+    final lineInfo = unit.lineInfo;
+    if (lineInfo == null) {
+      return null;
+    }
+
+    final accessorSourceSpans = _getUnusedAccessors(classElement, usages, unit);
+    final methodSourceSpans = _getUnusedMethods(classElement, usages, unit);
+
+    final filePath = unit.source.toString();
+    final relativePath = relative(filePath, from: rootFolder);
+
+    final issues = [
+      ...accessorSourceSpans,
+      ...methodSourceSpans,
+    ];
+
+    if (issues.isNotEmpty) {
+      return UnusedL10nFileReport(
+        path: filePath,
+        relativePath: relativePath,
+        className: overriddenClassName ?? classElement.name,
+        issues: issues,
+      );
+    }
+
+    return null;
+  }
+
   Iterable<UnusedL10nIssue> _getUnusedAccessors(
     ClassElement classElement,
     Iterable<String> usages,

test/resources/unused_l10n_analyzer/base_localization.dart

@@ -0,0 +1,5 @@
+class BaseLocalization {
+  String get baseGetter => 'getter';
+
+  String get anotherBaseGetter => 'getter'; // LINT
+}

test/resources/unused_l10n_analyzer/test_i18n.dart

@@ -1,4 +1,6 @@
-class TestI18n {
+import 'base_localization.dart';
+
+class TestI18n extends BaseLocalization {
   static const String field = 'field';
 
   static String get getter => 'getter'; // LINT

test/resources/unused_l10n_analyzer/unused_l10n_analyzer_example.dart

@@ -11,6 +11,8 @@ void main() {
 
   TestI18n.of('').anotherRegularGetter;
 
+  TestI18n.of('').baseGetter;
+
   final wrapper = L10nWrapper();
 
   wrapper.l10n.regularField.trim();

test/src/analyzers/unused_l10n_analyzer/unused_l10n_analyzer_test.dart

@@ -31,28 +31,35 @@ void main() {
           config,
         );
 
-        final report = result.single;
+        final report = result.firstWhere((report) => report.issues.length == 3);
         expect(report.className, 'TestI18n');
 
-        expect(report.issues.length, 3);
-
         final firstIssue = report.issues.first;
         expect(firstIssue.memberName, 'getter');
-        expect(firstIssue.location.line, 4);
+        expect(firstIssue.location.line, 6);
         expect(firstIssue.location.column, 3);
 
         final secondIssue = report.issues.elementAt(1);
         expect(secondIssue.memberName, 'regularGetter');
-        expect(secondIssue.location.line, 13);
+        expect(secondIssue.location.line, 15);
         expect(secondIssue.location.column, 3);
 
         final thirdIssue = report.issues.elementAt(2);
         expect(
           thirdIssue.memberName,
           'secondMethod(String value, num number)',
         );
-        expect(thirdIssue.location.line, 8);
+        expect(thirdIssue.location.line, 10);
         expect(thirdIssue.location.column, 3);
+
+        final parentReport =
+            result.firstWhere((report) => report.issues.length == 1);
+        expect(parentReport.className, 'TestI18n');
+
+        final firstParentIssue = parentReport.issues.first;
+        expect(firstParentIssue.memberName, 'anotherBaseGetter');
+        expect(firstParentIssue.location.line, 4);
+        expect(firstParentIssue.location.column, 3);
       });
 
       test('should analyze files with custom class pattern', () async {
@@ -74,25 +81,25 @@ void main() {
 
         final firstIssue = report.issues.first;
         expect(firstIssue.memberName, 'field');
-        expect(firstIssue.location.line, 25);
+        expect(firstIssue.location.line, 27);
         expect(firstIssue.location.column, 3);
 
         final secondIssue = report.issues.elementAt(1);
         expect(secondIssue.memberName, 'regularField');
-        expect(secondIssue.location.line, 42);
+        expect(secondIssue.location.line, 44);
         expect(secondIssue.location.column, 3);
 
         final thirdIssue = report.issues.elementAt(2);
         expect(thirdIssue.memberName, 'method(String value)');
-        expect(thirdIssue.location.line, 29);
+        expect(thirdIssue.location.line, 31);
         expect(thirdIssue.location.column, 3);
 
         final forthIssue = report.issues.elementAt(3);
         expect(
           forthIssue.memberName,
           'secondMethod(String value, num number)',
         );
-        expect(forthIssue.location.line, 31);
+        expect(forthIssue.location.line, 33);
         expect(forthIssue.location.column, 3);
       });