Extension type. Extension type is always exhaustive if the erasure is…

… always exhaustive. Bug: #54370 Bug: #54421 Change-Id: Iebd64c413f489ac12b1a8d56a987ad44df00534e Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/342729 Reviewed-by: Brian Wilkerson <brianwilkerson@google.com> Commit-Queue: Konstantin Shcheglov <scheglov@google.com>
dart-lang · Dec 20, 2023 · a1006f4 · a1006f4
1 parent 93c25ff
commit a1006f4
Show file tree

Hide file tree

Showing 4 changed files with 43 additions and 0 deletions.
diff --git a/pkg/analyzer/lib/src/dart/constant/constant_verifier.dart b/pkg/analyzer/lib/src/dart/constant/constant_verifier.dart
@@ -145,6 +145,7 @@ class ConstantVerifier extends RecursiveAstVisitor<void> {
         if (value.hasPrimitiveEquality(_currentLibrary.featureSet)) {
           var constantType = value.type;
           var matchedValueType = node.matchedValueType;
+          matchedValueType = matchedValueType?.extensionTypeErasure;
           if (matchedValueType != null) {
             if (!_canBeEqual(constantType, matchedValueType)) {
               _errorReporter.reportErrorForNode(

diff --git a/pkg/analyzer/lib/src/dart/element/type_system.dart b/pkg/analyzer/lib/src/dart/element/type_system.dart
@@ -879,6 +879,9 @@ class TypeSystemImpl implements TypeSystem {
       if (element is ClassElement && element.isSealed) {
         return true;
       }
+      if (element is ExtensionTypeElement) {
+        return isAlwaysExhaustive(type.extensionTypeErasure);
+      }
       if (type.isDartAsyncFutureOr) {
         return isAlwaysExhaustive(type.typeArguments[0]);
       }

diff --git a/pkg/analyzer/test/src/diagnostics/body_might_complete_normally_nullable_test.dart b/pkg/analyzer/test/src/diagnostics/body_might_complete_normally_nullable_test.dart
@@ -38,6 +38,23 @@ void f(Future f) async {}
 ''');
   }
 
+  test_function_switchStatement_exhaustive_extensionType() async {
+    await assertNoErrorsInCode(r'''
+enum E { a, b }
+
+extension type EE(E it) {}
+
+int f(EE e) {
+  switch (e) {
+    case E.a:
+      return 0;
+    case E.b:
+      return 1;
+  }
+}
+''');
+  }
+
   test_function_sync_block_dynamic() async {
     await assertNoErrorsInCode('''
 dynamic f() {}

diff --git a/pkg/analyzer/test/src/diagnostics/constant_pattern_never_matches_value_type_test.dart b/pkg/analyzer/test/src/diagnostics/constant_pattern_never_matches_value_type_test.dart
@@ -298,6 +298,28 @@ const zero = 0;
 ''');
   }
 
+  test_int_extensionTypeBool() async {
+    await assertErrorsInCode('''
+extension type E(bool it) {}
+
+void f(E x) {
+  if (x case (0)) {}
+}
+''', [
+      error(WarningCode.CONSTANT_PATTERN_NEVER_MATCHES_VALUE_TYPE, 58, 1),
+    ]);
+  }
+
+  test_int_extensionTypeInt() async {
+    await assertNoErrorsInCode('''
+extension type E(int it) {}
+
+void f(E x) {
+  if (x case (0)) {}
+}
+''');
+  }
+
   test_int_functionType() async {
     await assertErrorsInCode('''
 void f(void Function() x) {