Reorganize equivalence test helpers

tests/compiler/dart2js/kernel/test_helpers.dart

+// Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+library dart2js.kernel.equivalence;
+
+import 'package:compiler/src/common/backend_api.dart';
+import 'package:compiler/src/common/resolution.dart';
+import 'package:compiler/src/common/work.dart';
+import 'package:compiler/src/constants/expressions.dart';
+import 'package:compiler/src/constants/values.dart';
+import 'package:compiler/src/compiler.dart';
+import 'package:compiler/src/elements/elements.dart';
+import 'package:compiler/src/elements/entities.dart';
+import 'package:compiler/src/elements/resolution_types.dart';
+import 'package:compiler/src/elements/types.dart';
+import 'package:compiler/src/enqueue.dart';
+import 'package:compiler/src/kernel/elements.dart';
+import 'package:compiler/src/kernel/element_map_impl.dart';
+import 'package:compiler/src/serialization/equivalence.dart';
+import 'package:compiler/src/ssa/kernel_impact.dart';
+import 'package:compiler/src/universe/world_impact.dart';
+import 'package:compiler/src/util/util.dart';
+
+class KernelEquivalence {
+  final WorldDeconstructionForTesting testing;
+
+  /// Set of mixin applications assumed to be equivalent.
+  ///
+  /// We need co-inductive reasoning because mixin applications are compared
+  /// structurally and therefore, in the case of generic mixin applications,
+  /// meet themselves through the equivalence check of their type variables.
+  Set<Pair<ClassEntity, ClassEntity>> assumedMixinApplications =
+      new Set<Pair<ClassEntity, ClassEntity>>();
+
+  KernelEquivalence(KernelToElementMapImpl builder)
+      : testing = new WorldDeconstructionForTesting(builder);
+
+  TestStrategy get defaultStrategy => new TestStrategy(
+      elementEquivalence: entityEquivalence,
+      typeEquivalence: typeEquivalence,
+      constantEquivalence: constantEquivalence,
+      constantValueEquivalence: constantValueEquivalence);
+
+  bool entityEquivalence(Element a, Entity b, {TestStrategy strategy}) {
+    if (identical(a, b)) return true;
+    if (a == null || b == null) return false;
+    strategy ??= defaultStrategy;
+    switch (a.kind) {
+      case ElementKind.GENERATIVE_CONSTRUCTOR:
+        if (b is KGenerativeConstructor) {
+          return strategy.test(a, b, 'name', a.name, b.name) &&
+              strategy.testElements(
+                  a, b, 'enclosingClass', a.enclosingClass, b.enclosingClass);
+        }
+        return false;
+      case ElementKind.FACTORY_CONSTRUCTOR:
+        if (b is KFactoryConstructor) {
+          return strategy.test(a, b, 'name', a.name, b.name) &&
+              strategy.testElements(
+                  a, b, 'enclosingClass', a.enclosingClass, b.enclosingClass);
+        }
+        return false;
+      case ElementKind.CLASS:
+        if (b is KClass) {
+          List<InterfaceType> aMixinTypes = [];
+          List<InterfaceType> bMixinTypes = [];
+          ClassElement aClass = a;
+          if (aClass.isUnnamedMixinApplication) {
+            if (!testing.isUnnamedMixinApplication(b)) {
+              return false;
+            }
+            while (aClass.isMixinApplication) {
+              MixinApplicationElement aMixinApplication = aClass;
+              aMixinTypes.add(aMixinApplication.mixinType);
+              aClass = aMixinApplication.superclass;
+            }
+            KClass bClass = b;
+            while (bClass != null) {
+              InterfaceType mixinType = testing.getMixinTypeForClass(bClass);
+              if (mixinType == null) break;
+              bMixinTypes.add(mixinType);
+              bClass = testing.getSuperclassForClass(bClass);
+            }
+            if (aMixinTypes.isNotEmpty || aMixinTypes.isNotEmpty) {
+              Pair<ClassEntity, ClassEntity> pair =
+                  new Pair<ClassEntity, ClassEntity>(aClass, bClass);
+              if (assumedMixinApplications.contains(pair)) {
+                return true;
+              } else {
+                assumedMixinApplications.add(pair);
+                bool result = strategy.testTypeLists(
+                    a, b, 'mixinTypes', aMixinTypes, bMixinTypes);
+                assumedMixinApplications.remove(pair);
+                return result;
+              }
+            }
+          } else {
+            if (testing.isUnnamedMixinApplication(b)) {
+              return false;
+            }
+          }
+          return strategy.test(a, b, 'name', a.name, b.name) &&
+              strategy.testElements(a, b, 'library', a.library, b.library);
+        }
+        return false;
+      case ElementKind.LIBRARY:
+        if (b is KLibrary) {
+          LibraryElement libraryA = a;
+          return libraryA.canonicalUri == b.canonicalUri;
+        }
+        return false;
+      case ElementKind.FUNCTION:
+        if (b is KMethod) {
+          return strategy.test(a, b, 'name', a.name, b.name) &&
+              strategy.testElements(
+                  a, b, 'enclosingClass', a.enclosingClass, b.enclosingClass) &&
+              strategy.testElements(a, b, 'library', a.library, b.library);
+        } else if (b is KLocalFunction) {
+          LocalFunctionElement aLocalFunction = a;
+          return strategy.test(a, b, 'name', a.name, b.name ?? '') &&
+              strategy.testElements(a, b, 'executableContext',
+                  aLocalFunction.executableContext, b.executableContext) &&
+              strategy.testElements(a, b, 'memberContext',
+                  aLocalFunction.memberContext, b.memberContext);
+        }
+        return false;
+      case ElementKind.GETTER:
+        if (b is KGetter) {
+          return strategy.test(a, b, 'name', a.name, b.name) &&
+              strategy.testElements(
+                  a, b, 'enclosingClass', a.enclosingClass, b.enclosingClass) &&
+              strategy.testElements(a, b, 'library', a.library, b.library);
+        }
+        return false;
+      case ElementKind.SETTER:
+        if (b is KSetter) {
+          return strategy.test(a, b, 'name', a.name, b.name) &&
+              strategy.testElements(
+                  a, b, 'enclosingClass', a.enclosingClass, b.enclosingClass) &&
+              strategy.testElements(a, b, 'library', a.library, b.library);
+        }
+        return false;
+      case ElementKind.FIELD:
+        if (b is KField) {
+          return strategy.test(a, b, 'name', a.name, b.name) &&
+              strategy.testElements(
+                  a, b, 'enclosingClass', a.enclosingClass, b.enclosingClass) &&
+              strategy.testElements(a, b, 'library', a.library, b.library);
+        }
+        return false;
+      case ElementKind.TYPE_VARIABLE:
+        if (b is KTypeVariable) {
+          TypeVariableElement aElement = a;
+          return strategy.test(a, b, 'index', aElement.index, b.index) &&
+              strategy.testElements(a, b, 'typeDeclaration',
+                  aElement.typeDeclaration, b.typeDeclaration);
+        }
+        return false;
+      default:
+        throw new UnsupportedError('Unsupported equivalence: '
+            '$a (${a.runtimeType}) vs $b (${b.runtimeType})');
+    }
+  }
+
+  bool typeEquivalence(ResolutionDartType a, DartType b,
+      {TestStrategy strategy}) {
+    if (identical(a, b)) return true;
+    if (a == null || b == null) return false;
+    strategy ??= defaultStrategy;
+    switch (a.kind) {
+      case ResolutionTypeKind.DYNAMIC:
+        return b is DynamicType;
+      case ResolutionTypeKind.VOID:
+        return b is VoidType;
+      case ResolutionTypeKind.INTERFACE:
+        if (b is InterfaceType) {
+          ResolutionInterfaceType aType = a;
+          return strategy.testElements(a, b, 'element', a.element, b.element) &&
+              strategy.testTypeLists(
+                  a, b, 'typeArguments', aType.typeArguments, b.typeArguments);
+        }
+        return false;
+      case ResolutionTypeKind.TYPE_VARIABLE:
+        if (b is TypeVariableType) {
+          return strategy.testElements(a, b, 'element', a.element, b.element);
+        }
+        return false;
+      case ResolutionTypeKind.FUNCTION:
+        if (b is FunctionType) {
+          ResolutionFunctionType aType = a;
+          return strategy.testTypes(
+                  a, b, 'returnType', aType.returnType, b.returnType) &&
+              strategy.testTypeLists(a, b, 'parameterTypes',
+                  aType.parameterTypes, b.parameterTypes) &&
+              strategy.testTypeLists(a, b, 'optionalParameterTypes',
+                  aType.optionalParameterTypes, b.optionalParameterTypes) &&
+              strategy.testLists(a, b, 'namedParameters', aType.namedParameters,
+                  b.namedParameters) &&
+              strategy.testTypeLists(a, b, 'namedParameterTypes',
+                  aType.namedParameterTypes, b.namedParameterTypes);
+        }
+        return false;
+      default:
+        throw new UnsupportedError('Unsupported equivalence: '
+            '$a (${a.runtimeType}) vs $b (${b.runtimeType})');
+    }
+  }
+
+  bool constantEquivalence(ConstantExpression exp1, ConstantExpression exp2,
+      {TestStrategy strategy}) {
+    strategy ??= defaultStrategy;
+    return areConstantsEquivalent(exp1, exp2, strategy: strategy);
+  }
+
+  bool constantValueEquivalence(ConstantValue value1, ConstantValue value2,
+      {TestStrategy strategy}) {
+    strategy ??= defaultStrategy;
+    return areConstantValuesEquivalent(value1, value2, strategy: strategy);
+  }
+}
+
+class KernelTestWorkItemBuilder implements WorkItemBuilder {
+  final Compiler _compiler;
+
+  KernelTestWorkItemBuilder(this._compiler);
+
+  @override
+  WorkItem createWorkItem(MemberEntity entity) {
+    return new KernelTestWorkItem(
+        _compiler, _compiler.backend.impactTransformer, entity);
+  }
+}
+
+class KernelTestWorkItem implements ResolutionWorkItem {
+  final Compiler _compiler;
+  final ImpactTransformer _impactTransformer;
+  final MemberElement element;
+
+  KernelTestWorkItem(this._compiler, this._impactTransformer, this.element);
+
+  @override
+  WorldImpact run() {
+    ResolutionImpact resolutionImpact = build(_compiler, element.resolvedAst);
+    return _impactTransformer.transformResolutionImpact(resolutionImpact);
+  }
+}
+
+/// Visitor the performers unaliasing of all typedefs nested within a
+/// [ResolutionDartType].
+class Unaliaser
+    extends BaseResolutionDartTypeVisitor<dynamic, ResolutionDartType> {
+  const Unaliaser();
+
+  @override
+  ResolutionDartType visit(ResolutionDartType type, [_]) =>
+      type.accept(this, null);
+
+  @override
+  ResolutionDartType visitType(ResolutionDartType type, _) => type;
+
+  List<ResolutionDartType> visitList(List<ResolutionDartType> types) =>
+      types.map(visit).toList();
+
+  @override
+  ResolutionDartType visitInterfaceType(ResolutionInterfaceType type, _) {
+    return type.createInstantiation(visitList(type.typeArguments));
+  }
+
+  @override
+  ResolutionDartType visitTypedefType(ResolutionTypedefType type, _) {
+    return visit(type.unaliased);
+  }
+
+  @override
+  ResolutionDartType visitFunctionType(ResolutionFunctionType type, _) {
+    return new ResolutionFunctionType.synthesized(
+        visit(type.returnType),
+        visitList(type.parameterTypes),
+        visitList(type.optionalParameterTypes),
+        type.namedParameters,
+        visitList(type.namedParameterTypes));
+  }
+}
+
+/// Perform unaliasing of all typedefs nested within a [ResolutionDartType].
+ResolutionDartType unalias(ResolutionDartType type) {
+  return const Unaliaser().visit(type);
+}
+
+bool elementFilter(Entity element) {
+  if (element is ConstructorElement && element.isRedirectingFactory) {
+    // Redirecting factory constructors are skipped in kernel.
+    return false;
+  }
+  if (element is ClassElement) {
+    for (ConstructorElement constructor in element.constructors) {
+      if (!constructor.isRedirectingFactory) {
+        return true;
+      }
+    }
+    // The class cannot itself be instantiated.
+    return false;
+  }
+  return true;
+}