feat: avoid non null assertion ignored types (#313)

* feat: add ignored_types configuration to avoid_non_null_assertion lint rule

* refactor: extract analysis options configuration to a constant in avoid_non_null_assertion test

* refactor: update ignoredTypes to a Set and improve JSON parsing to support string or map inputs

* refactor: update avoid_non_null_assertion parameter parsing to correctly extract keys from maps

* refactor: improve type safety and readability of AvoidNonNullAssertionParameters JSON decoding using typed patterns

---------

Co-authored-by: Illia Aihistov <illia.aihistov-us@solid.software>

Author: solid-illiaaihistov

lib/analysis_options.yaml

@@ -43,7 +43,10 @@ solid_lints:
       allow_initialized: true
       ignored_types:
         - AnimationController
-    avoid_non_null_assertion: true
+    avoid_non_null_assertion:
+      ignored_types:
+        - IMap
+        - BuiltMap
     avoid_returning_widgets: true
     avoid_unnecessary_return_variable: true
     avoid_unnecessary_setstate: true

lib/main.dart

@@ -66,7 +66,7 @@ class SolidLintsPlugin extends Plugin {
     final lintRules = [
       AvoidFinalWithGetterRule(),
       AvoidGlobalStateRule(),
-      AvoidNonNullAssertionRule(),
+      AvoidNonNullAssertionRule(analysisOptionsLoader: analysisLoader),
       avoidUnnecessaryTypeAssertionsRule,
       AvoidDebugPrintInReleaseRule(),
       doubleLiteralFormatRule,

lib/src/lints/avoid_non_null_assertion/avoid_non_null_assertion_rule.dart

@@ -1,8 +1,9 @@
-import 'package:analyzer/analysis_rule/analysis_rule.dart';
 import 'package:analyzer/analysis_rule/rule_context.dart';
 import 'package:analyzer/analysis_rule/rule_visitor_registry.dart';
 import 'package:analyzer/error/error.dart';
+import 'package:solid_lints/src/lints/avoid_non_null_assertion/models/avoid_non_null_assertion_parameters.dart';
 import 'package:solid_lints/src/lints/avoid_non_null_assertion/visitors/avoid_non_null_assertion_visitor.dart';
+import 'package:solid_lints/src/models/solid_lint_rule.dart';
 
 /// Rule which warns about usages of bang operator ("!")
 /// as it may result in unexpected runtime exceptions.
@@ -35,7 +36,8 @@ import 'package:solid_lints/src/lints/avoid_non_null_assertion/visitors/avoid_no
 /// final map = {'key': 'value'};
 /// map['key']!;
 /// ```
-class AvoidNonNullAssertionRule extends AnalysisRule {
+class AvoidNonNullAssertionRule
+    extends SolidLintRule<AvoidNonNullAssertionParameters> {
   /// Name of the lint
   static const String lintName = 'avoid_non_null_assertion';
 
@@ -46,11 +48,12 @@ class AvoidNonNullAssertionRule extends AnalysisRule {
   );
 
   /// creates an instance of [AvoidNonNullAssertionRule]
-  AvoidNonNullAssertionRule()
-    : super(
+  AvoidNonNullAssertionRule({required super.analysisOptionsLoader})
+    : super.withParameters(
         name: lintName,
         description:
             'Warns about usages of bang operator (!) except valid Map access.',
+        parametersParser: AvoidNonNullAssertionParameters.fromJson,
       );
 
   @override
@@ -61,6 +64,13 @@ class AvoidNonNullAssertionRule extends AnalysisRule {
     RuleVisitorRegistry registry,
     RuleContext context,
   ) {
-    registry.addPostfixExpression(this, AvoidNonNullAssertionVisitor(this));
+    final parameters =
+        getParametersForContext(context) ??
+        AvoidNonNullAssertionParameters.empty();
+
+    registry.addPostfixExpression(
+      this,
+      AvoidNonNullAssertionVisitor(this, parameters),
+    );
   }
 }

lib/src/lints/avoid_non_null_assertion/models/avoid_non_null_assertion_parameters.dart

@@ -0,0 +1,49 @@
+/// A data model class that represents the "avoid non null assertion" input
+/// parameters.
+class AvoidNonNullAssertionParameters {
+  /// Types that would be ignored by avoid-non-null-assertion rule
+  ///
+  /// Example:
+  ///
+  /// ```yaml
+  /// plugins:
+  ///   solid_lints:
+  ///     diagnostics:
+  ///       avoid_non_null_assertion:
+  ///         ignored_types:
+  ///           - IMap
+  /// ```
+  ///
+  /// ```dart
+  /// IMap<String, String> map;
+  /// map['key']!; // OK
+  /// ```
+  final Set<String> ignoredTypes;
+
+  /// Constructor for [AvoidNonNullAssertionParameters] model
+  const AvoidNonNullAssertionParameters({
+    required this.ignoredTypes,
+  });
+
+  /// Empty [AvoidNonNullAssertionParameters] model, ignores nothing.
+  factory AvoidNonNullAssertionParameters.empty() =>
+      const AvoidNonNullAssertionParameters(
+        ignoredTypes: {},
+      );
+
+  /// Method for creating from json data
+  factory AvoidNonNullAssertionParameters.fromJson(Map<String, Object?> json) {
+    final raw = json['ignored_types'];
+    final excludeList = switch (raw) {
+      final Iterable<Object?> rawList => rawList.whereType<String>().toSet(),
+      final Map<Object?, Object?> rawMap =>
+        rawMap.keys.whereType<String>().toSet(),
+      final String rawString => {rawString},
+      _ => const <String>{},
+    };
+
+    return AvoidNonNullAssertionParameters(
+      ignoredTypes: excludeList,
+    );
+  }
+}

lib/src/lints/avoid_non_null_assertion/visitors/avoid_non_null_assertion_visitor.dart

@@ -3,27 +3,31 @@ import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:solid_lints/src/lints/avoid_non_null_assertion/avoid_non_null_assertion_rule.dart';
+import 'package:solid_lints/src/lints/avoid_non_null_assertion/models/avoid_non_null_assertion_parameters.dart';
+import 'package:solid_lints/src/utils/types_utils.dart';
 
 /// visitor for [AvoidNonNullAssertionRule]
 class AvoidNonNullAssertionVisitor extends SimpleAstVisitor<void> {
   /// Rule associated with this visitor
   final AvoidNonNullAssertionRule rule;
 
+  final AvoidNonNullAssertionParameters _parameters;
+
   /// Creates an instance of [AvoidNonNullAssertionVisitor]
-  AvoidNonNullAssertionVisitor(this.rule);
+  AvoidNonNullAssertionVisitor(this.rule, this._parameters);
 
   @override
   void visitPostfixExpression(PostfixExpression node) {
     if (node.operator.type != TokenType.BANG) {
       return;
     }
 
-    final operand = node.operand;
+    final operand = node.operand.unParenthesized;
 
     if (operand is IndexExpression) {
       final type = operand.target?.staticType;
 
-      if (_isMap(type)) {
+      if (_isMap(type) || _hasIgnoredType(type)) {
         return;
       }
     }
@@ -38,4 +42,14 @@ class AvoidNonNullAssertionVisitor extends SimpleAstVisitor<void> {
 
     return type.isDartCoreMap || type.allSupertypes.any((v) => v.isDartCoreMap);
   }
+
+  bool _hasIgnoredType(DartType? type) {
+    if (type == null) {
+      return false;
+    }
+
+    return type.hasIgnoredType(
+      ignoredTypes: _parameters.ignoredTypes,
+    );
+  }
 }

test/lints/avoid_non_null_assertion/avoid_non_null_assertion_rule_test.dart

@@ -1,4 +1,6 @@
 import 'package:analyzer_testing/analysis_rule/analysis_rule.dart';
+import 'package:analyzer_testing/utilities/utilities.dart';
+import 'package:solid_lints/src/common/parameter_parser/analysis_options_loader.dart';
 import 'package:solid_lints/src/lints/avoid_non_null_assertion/avoid_non_null_assertion_rule.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
@@ -13,10 +15,30 @@ void main() {
 @reflectiveTest
 class AvoidNonNullAssertionRuleTest extends AnalysisRuleTest
     with AutoTestLintOffsets {
+  static const _mockAnalysisOptionsContent = '''
+plugins:
+  solid_lints:
+    diagnostics:
+      avoid_non_null_assertion:
+        ignored_types:
+          - IMap
+          - BuiltMap
+  ''';
+
   @override
   void setUp() {
-    rule = AvoidNonNullAssertionRule();
+    rule = AvoidNonNullAssertionRule(
+      analysisOptionsLoader: AnalysisOptionsLoader(
+        resourceProvider: resourceProvider,
+      ),
+    );
     super.setUp();
+
+    newAnalysisOptionsYamlFile(
+      testPackageRootPath,
+      '''${analysisOptionsContent(rules: [rule.name])}
+$_mockAnalysisOptionsContent''',
+    );
   }
 
   Future<void> test_reports_non_null_assertion_on_nullable_value() async {
@@ -51,6 +73,48 @@ void m(int? number) {
     final value = number;
   }
 }
+''');
+  }
+
+  Future<void> test_does_not_report_imap_access() async {
+    await assertNoDiagnostics(r'''
+class IMap<K, V> {
+  V? operator [](K key) => null;
+}
+
+void m(IMap<String, String> map) {
+  map['key']!;
+}
+''');
+  }
+
+  Future<void> test_does_not_report_parenthesized_map_access() async {
+    await assertNoDiagnostics(r'''
+void m() {
+  final map = {'key': 'value'};
+  (map['key'])!;
+}
+''');
+  }
+
+  Future<void> test_does_not_report_imap_access_with_single_string() async {
+    newAnalysisOptionsYamlFile(
+      testPackageRootPath,
+      '''${analysisOptionsContent(rules: [rule.name])}
+plugins:
+  solid_lints:
+    diagnostics:
+      avoid_non_null_assertion:
+        ignored_types: IMap''',
+    );
+    await assertNoDiagnostics(r'''
+class IMap<K, V> {
+  V? operator [](K key) => null;
+}
+
+void m(IMap<String, String> map) {
+  map['key']!;
+}
 ''');
   }
 }