[CFE] Fix crash in _computeOnClause

If a mixin refers to a non-existing class (or Function) it doesn't get
the otherwise expected number of implementedTypes and crashes.

Fixes #59870

Change-Id: I482e997751b36c5d62d2151b31bd58875d86ebf3
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/403602
Reviewed-by: Johnni Winther <[email protected]>
Commit-Queue: Jens Johansen <[email protected]>

Author: jensjoha

pkg/front_end/lib/src/base/crash.dart

@@ -65,7 +65,10 @@ Future<T> reportCrash<T>(error, StackTrace trace,
     await stderr.flush();
   }
 
-  if (hasCrashed) return new Future<T>.error(error, trace);
+  if (hasCrashed) {
+    // Coverage-ignore-block(suite): Not run.
+    return new Future<T>.error(error, trace);
+  }
   if (error is Crash) {
     // Coverage-ignore-block(suite): Not run.
     trace = error.trace ?? trace;
@@ -137,7 +140,9 @@ Future<T> withCrashReporting<T>(
   } on DebugAbort {
     rethrow;
   } catch (e, s) {
-    if (e is Crash && e._hasBeenReported) {
+    if (e is Crash &&
+        // Coverage-ignore(suite): Not run.
+        e._hasBeenReported) {
       rethrow;
     }
     UriOffset? uriOffset = currentUriOffset();

pkg/front_end/lib/src/kernel/forest.dart

@@ -671,8 +671,7 @@ class Forest {
 
   TypeParameterType createTypeParameterTypeWithDefaultNullabilityForLibrary(
       TypeParameter typeParameter, Library library) {
-    return new TypeParameterType.withDefaultNullability(
-        typeParameter);
+    return new TypeParameterType.withDefaultNullability(typeParameter);
   }
 
   Expression createExpressionInvocation(

pkg/front_end/lib/src/kernel/hierarchy/hierarchy_node.dart

@@ -89,7 +89,6 @@ abstract class HierarchyNodeBuilder {
         if (interfaces.length == 1) {
           return null;
         } else {
-          // Coverage-ignore-block(suite): Not run.
           interfaces = interfaces.toList();
           interfaces.removeAt(i);
           return _ignoreFunction(interfaces);

pkg/front_end/lib/src/type_inference/type_schema.dart

@@ -57,7 +57,6 @@ class UnknownType extends AuxiliaryType
   Nullability get declaredNullability => Nullability.undetermined;
 
   @override
-  // Coverage-ignore(suite): Not run.
   Nullability get nullability => Nullability.undetermined;
 
   @override

pkg/front_end/lib/src/type_inference/type_schema_environment.dart

@@ -481,7 +481,6 @@ class TypeSchemaEnvironment extends HierarchyBasedTypeEnvironment
     if (inferenceUsingBoundsIsEnabled &&
         constraint.lower is! SharedUnknownTypeSchemaView<DartType> &&
         !hasOmittedBound(typeParameterToInfer)) {
-      // Coverage-ignore-block(suite): Not run.
       MergedTypeConstraint constraintFromBound =
           operations.mergeInConstraintsFromBound(
               typeParameterToInfer: typeParameterToInfer,

pkg/front_end/test/coverage_suite_expected.dart

@@ -110,7 +110,7 @@ const Map<String, ({int hitCount, int missCount})> _expect = {
   ),
   // 100.0%.
   "package:front_end/src/base/crash.dart": (
-    hitCount: 52,
+    hitCount: 50,
     missCount: 0,
   ),
   // 100.0%.
@@ -530,7 +530,7 @@ const Map<String, ({int hitCount, int missCount})> _expect = {
   ),
   // 100.0%.
   "package:front_end/src/fragment/method.dart": (
-    hitCount: 758,
+    hitCount: 759,
     missCount: 0,
   ),
   // 100.0%.
@@ -575,7 +575,7 @@ const Map<String, ({int hitCount, int missCount})> _expect = {
   ),
   // 100.0%.
   "package:front_end/src/kernel/body_builder.dart": (
-    hitCount: 7182,
+    hitCount: 7181,
     missCount: 0,
   ),
   // 100.0%.
@@ -595,7 +595,7 @@ const Map<String, ({int hitCount, int missCount})> _expect = {
   ),
   // 100.0%.
   "package:front_end/src/kernel/combined_member_signature.dart": (
-    hitCount: 385,
+    hitCount: 380,
     missCount: 0,
   ),
   // 100.0%.
@@ -640,7 +640,7 @@ const Map<String, ({int hitCount, int missCount})> _expect = {
   ),
   // 100.0%.
   "package:front_end/src/kernel/expression_generator_helper.dart": (
-    hitCount: 36,
+    hitCount: 35,
     missCount: 0,
   ),
   // 100.0%.
@@ -650,7 +650,7 @@ const Map<String, ({int hitCount, int missCount})> _expect = {
   ),
   // 100.0%.
   "package:front_end/src/kernel/forwarding_node.dart": (
-    hitCount: 326,
+    hitCount: 323,
     missCount: 0,
   ),
   // 100.0%.
@@ -675,7 +675,7 @@ const Map<String, ({int hitCount, int missCount})> _expect = {
   ),
   // 100.0%.
   "package:front_end/src/kernel/hierarchy/hierarchy_node.dart": (
-    hitCount: 400,
+    hitCount: 403,
     missCount: 0,
   ),
   // 100.0%.
@@ -690,7 +690,7 @@ const Map<String, ({int hitCount, int missCount})> _expect = {
   ),
   // 100.0%.
   "package:front_end/src/kernel/hierarchy/mixin_inferrer.dart": (
-    hitCount: 248,
+    hitCount: 244,
     missCount: 0,
   ),
   // 100.0%.
@@ -725,7 +725,7 @@ const Map<String, ({int hitCount, int missCount})> _expect = {
   ),
   // 100.0%.
   "package:front_end/src/kernel/kernel_target.dart": (
-    hitCount: 1076,
+    hitCount: 1075,
     missCount: 0,
   ),
   // 100.0%.
@@ -905,7 +905,7 @@ const Map<String, ({int hitCount, int missCount})> _expect = {
   ),
   // 100.0%.
   "package:front_end/src/source/source_class_builder.dart": (
-    hitCount: 1276,
+    hitCount: 1274,
     missCount: 0,
   ),
   // 100.0%.
@@ -915,7 +915,7 @@ const Map<String, ({int hitCount, int missCount})> _expect = {
   ),
   // 100.0%.
   "package:front_end/src/source/source_constructor_builder.dart": (
-    hitCount: 898,
+    hitCount: 891,
     missCount: 0,
   ),
   // 100.0%.
@@ -936,7 +936,7 @@ const Map<String, ({int hitCount, int missCount})> _expect = {
   ),
   // 100.0%.
   "package:front_end/src/source/source_factory_builder.dart": (
-    hitCount: 597,
+    hitCount: 593,
     missCount: 0,
   ),
   // 100.0%.
@@ -946,7 +946,7 @@ const Map<String, ({int hitCount, int missCount})> _expect = {
   ),
   // 100.0%.
   "package:front_end/src/source/source_function_builder.dart": (
-    hitCount: 249,
+    hitCount: 243,
     missCount: 0,
   ),
   // 100.0%.
@@ -971,7 +971,7 @@ const Map<String, ({int hitCount, int missCount})> _expect = {
   ),
   // 100.0%.
   "package:front_end/src/source/source_property_builder.dart": (
-    hitCount: 769,
+    hitCount: 766,
     missCount: 0,
   ),
   // 100.0%.
@@ -1026,12 +1026,12 @@ const Map<String, ({int hitCount, int missCount})> _expect = {
   ),
   // 100.0%.
   "package:front_end/src/type_inference/inference_visitor.dart": (
-    hitCount: 8264,
+    hitCount: 8260,
     missCount: 0,
   ),
   // 100.0%.
   "package:front_end/src/type_inference/inference_visitor_base.dart": (
-    hitCount: 2444,
+    hitCount: 2439,
     missCount: 0,
   ),
   // 100.0%.
@@ -1061,7 +1061,7 @@ const Map<String, ({int hitCount, int missCount})> _expect = {
   ),
   // 100.0%.
   "package:front_end/src/type_inference/type_constraint_gatherer.dart": (
-    hitCount: 109,
+    hitCount: 103,
     missCount: 0,
   ),
   // 100.0%.
@@ -1071,7 +1071,7 @@ const Map<String, ({int hitCount, int missCount})> _expect = {
   ),
   // 100.0%.
   "package:front_end/src/type_inference/type_inference_engine.dart": (
-    hitCount: 530,
+    hitCount: 533,
     missCount: 0,
   ),
   // 100.0%.
@@ -1081,7 +1081,7 @@ const Map<String, ({int hitCount, int missCount})> _expect = {
   ),
   // 100.0%.
   "package:front_end/src/type_inference/type_schema.dart": (
-    hitCount: 11,
+    hitCount: 12,
     missCount: 0,
   ),
   // 100.0%.
@@ -1091,7 +1091,7 @@ const Map<String, ({int hitCount, int missCount})> _expect = {
   ),
   // 100.0%.
   "package:front_end/src/type_inference/type_schema_environment.dart": (
-    hitCount: 263,
+    hitCount: 255,
     missCount: 0,
   ),
   // 100.0%.

pkg/front_end/test/spell_checking_list_tests.txt

@@ -419,6 +419,7 @@ ia
 identification
 idle
 if's
+ij
 ikg
 illustrate
 image

pkg/front_end/testcases/general/crashes/crash_02/main.dart.strong.expect

@@ -0,0 +1,46 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/crashes/crash_02/main.dart:1:15: Error: Type 'E' not found.
+// mixin A on D, E {}
+//               ^
+//
+// pkg/front_end/testcases/general/crashes/crash_02/main.dart:3:7: Error: 'C' doesn't implement '_A&D&E' so it can't be used with 'A'.
+//  - 'C' is from 'pkg/front_end/testcases/general/crashes/crash_02/main.dart'.
+//  - 'D with E' is from 'pkg/front_end/testcases/general/crashes/crash_02/main.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/crashes/crash_02/main.dart'.
+// class B extends C with A {}
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class _A&D&E extends core::Object implements self::D /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A&D&E
+    : super core::Object::•()
+    ;
+}
+abstract class A extends self::_A&D&E /*isMixinDeclaration*/  {
+}
+abstract class _B&C&A = self::C with self::A /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_B&C&A
+    : super self::C::•()
+    ;
+}
+class B extends self::_B&C&A {
+  synthetic constructor •() → self::B
+    : super self::_B&C&A::•()
+    ;
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+}
+class D extends core::Object {
+  synthetic constructor •() → self::D
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {}

pkg/front_end/testcases/general/crashes/crash_02/main.dart.strong.modular.expect

@@ -0,0 +1,46 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/crashes/crash_02/main.dart:1:15: Error: Type 'E' not found.
+// mixin A on D, E {}
+//               ^
+//
+// pkg/front_end/testcases/general/crashes/crash_02/main.dart:3:7: Error: 'C' doesn't implement '_A&D&E' so it can't be used with 'A'.
+//  - 'C' is from 'pkg/front_end/testcases/general/crashes/crash_02/main.dart'.
+//  - 'D with E' is from 'pkg/front_end/testcases/general/crashes/crash_02/main.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/crashes/crash_02/main.dart'.
+// class B extends C with A {}
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class _A&D&E extends core::Object implements self::D /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A&D&E
+    : super core::Object::•()
+    ;
+}
+abstract class A extends self::_A&D&E /*isMixinDeclaration*/  {
+}
+abstract class _B&C&A = self::C with self::A /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_B&C&A
+    : super self::C::•()
+    ;
+}
+class B extends self::_B&C&A {
+  synthetic constructor •() → self::B
+    : super self::_B&C&A::•()
+    ;
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+}
+class D extends core::Object {
+  synthetic constructor •() → self::D
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {}

pkg/front_end/testcases/general/crashes/crash_02/main.dart.strong.outline.expect

@@ -0,0 +1,43 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/crashes/crash_02/main.dart:1:15: Error: Type 'E' not found.
+// mixin A on D, E {}
+//               ^
+//
+// pkg/front_end/testcases/general/crashes/crash_02/main.dart:3:7: Error: 'C' doesn't implement '_A&D&E' so it can't be used with 'A'.
+//  - 'C' is from 'pkg/front_end/testcases/general/crashes/crash_02/main.dart'.
+//  - 'D with E' is from 'pkg/front_end/testcases/general/crashes/crash_02/main.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/crashes/crash_02/main.dart'.
+// class B extends C with A {}
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class _A&D&E extends core::Object implements self::D /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A&D&E
+    ;
+}
+abstract class A extends self::_A&D&E /*isMixinDeclaration*/  {
+}
+abstract class _B&C&A = self::C with self::A /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_B&C&A
+    : super self::C::•()
+    ;
+}
+class B extends self::_B&C&A {
+  synthetic constructor •() → self::B
+    ;
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C
+    ;
+}
+class D extends core::Object {
+  synthetic constructor •() → self::D
+    ;
+}
+static method main() → dynamic
+  ;