Reorganize equivalence test helpers

tests/compiler/dart2js/serialization/test_helper.dart

Index: tests/compiler/dart2js/serialization/test_helper.dart
diff --git a/tests/compiler/dart2js/serialization/test_helper.dart b/tests/compiler/dart2js/serialization/test_helper.dart
index 0e5c36668f463980d23ff3823ea754f9c9680a47..e73f8c09c13f5d23d1ff0c3c4e32506a06c950c3 100644
--- a/tests/compiler/dart2js/serialization/test_helper.dart
+++ b/tests/compiler/dart2js/serialization/test_helper.dart
@@ -20,591 +20,6 @@ import 'package:compiler/src/util/util.dart';
 import 'package:expect/expect.dart';
 import 'test_data.dart';
 
-Check currentCheck;
-
-class Check {
-  final Check parent;
-  final Object object1;
-  final Object object2;
-  final String property;
-  final Object value1;
-  final Object value2;
-
-  Check(this.parent, this.object1, this.object2, this.property, this.value1,
-      this.value2);
-
-  String printOn(StringBuffer sb, String indent) {
-    if (parent != null) {
-      indent = parent.printOn(sb, indent);
-      sb.write('\n$indent|\n');
-    }
-    sb.write("${indent}property='$property'\n ");
-    sb.write("${indent}object1=$object1 (${object1.runtimeType})\n ");
-    sb.write("${indent}value=${value1 == null ? "null" : "'$value1'"} ");
-    sb.write("(${value1.runtimeType}) vs\n ");
-    sb.write("${indent}object2=$object2 (${object2.runtimeType})\n ");
-    sb.write("${indent}value=${value2 == null ? "null" : "'$value2'"} ");
-    sb.write("(${value2.runtimeType})");
-    return ' $indent';
-  }
-
-  String toString() {
-    StringBuffer sb = new StringBuffer();
-    printOn(sb, '');
-    return sb.toString();
-  }
-}
-
-/// Strategy for checking equivalence.
-///
-/// Use this strategy to fail early with contextual information in the event of
-/// inequivalence.
-class CheckStrategy extends TestStrategy {
-  const CheckStrategy(
-      {Equivalence<Entity> elementEquivalence: areElementsEquivalent,
-      Equivalence<DartType> typeEquivalence: areTypesEquivalent,
-      Equivalence<ConstantExpression> constantEquivalence:
-          areConstantsEquivalent,
-      Equivalence<ConstantValue> constantValueEquivalence:
-          areConstantValuesEquivalent})
-      : super(
-            elementEquivalence: elementEquivalence,
-            typeEquivalence: typeEquivalence,
-            constantEquivalence: constantEquivalence,
-            constantValueEquivalence: constantValueEquivalence);
-
-  TestStrategy get testOnly => new TestStrategy(
-      elementEquivalence: elementEquivalence,
-      typeEquivalence: typeEquivalence,
-      constantEquivalence: constantEquivalence,
-      constantValueEquivalence: constantValueEquivalence);
-
-  @override
-  bool test(var object1, var object2, String property, var value1, var value2,
-      [bool equivalence(a, b) = equality]) {
-    return check(object1, object2, property, value1, value2, equivalence);
-  }
-
-  @override
-  bool testLists(
-      Object object1, Object object2, String property, List list1, List list2,
-      [bool elementEquivalence(a, b) = equality]) {
-    return checkListEquivalence(object1, object2, property, list1, list2,
-        (o1, o2, p, v1, v2) {
-      if (!elementEquivalence(v1, v2)) {
-        throw "$o1.$p = '${v1}' <> "
-            "$o2.$p = '${v2}'";
-      }
-      return true;
-    });
-  }
-
-  @override
-  bool testSets(
-      var object1, var object2, String property, Iterable set1, Iterable set2,
-      [bool elementEquivalence(a, b) = equality]) {
-    return checkSetEquivalence(
-        object1, object2, property, set1, set2, elementEquivalence);
-  }
-
-  @override
-  bool testMaps(var object1, var object2, String property, Map map1, Map map2,
-      [bool keyEquivalence(a, b) = equality,
-      bool valueEquivalence(a, b) = equality]) {
-    return checkMapEquivalence(object1, object2, property, map1, map2,
-        keyEquivalence, valueEquivalence);
-  }
-}
-
-/// Check that the values [property] of [object1] and [object2], [value1] and
-/// [value2] respectively, are equal and throw otherwise.
-bool check(var object1, var object2, String property, var value1, var value2,
-    [bool equivalence(a, b) = equality]) {
-  currentCheck =
-      new Check(currentCheck, object1, object2, property, value1, value2);
-  if (!equivalence(value1, value2)) {
-    throw currentCheck;
-  }
-  currentCheck = currentCheck.parent;
-  return true;
-}
-
-/// Check equivalence of the two lists, [list1] and [list2], using
-/// [checkEquivalence] to check the pair-wise equivalence.
-///
-/// Uses [object1], [object2] and [property] to provide context for failures.
-bool checkListEquivalence(
-    Object object1,
-    Object object2,
-    String property,
-    Iterable list1,
-    Iterable list2,
-    void checkEquivalence(o1, o2, property, a, b)) {
-  currentCheck =
-      new Check(currentCheck, object1, object2, property, list1, list2);
-  for (int i = 0; i < list1.length && i < list2.length; i++) {
-    checkEquivalence(
-        object1, object2, property, list1.elementAt(i), list2.elementAt(i));
-  }
-  for (int i = list1.length; i < list2.length; i++) {
-    throw 'Missing equivalent for element '
-        '#$i ${list2.elementAt(i)} in `${property}` on $object2.\n'
-        '`${property}` on $object1:\n ${list1.join('\n ')}\n'
-        '`${property}` on $object2:\n ${list2.join('\n ')}';
-  }
-  for (int i = list2.length; i < list1.length; i++) {
-    throw 'Missing equivalent for element '
-        '#$i ${list1.elementAt(i)} in `${property}` on $object1.\n'
-        '`${property}` on $object1:\n ${list1.join('\n ')}\n'
-        '`${property}` on $object2:\n ${list2.join('\n ')}';
-  }
-  currentCheck = currentCheck.parent;
-  return true;
-}
-
-/// Computes the set difference between [set1] and [set2] using
-/// [elementEquivalence] to determine element equivalence.
-///
-/// Elements both in [set1] and [set2] are added to [common], elements in [set1]
-/// but not in [set2] are added to [unfound], and the set of elements in [set2]
-/// but not in [set1] are returned.
-Set computeSetDifference(
-    Iterable set1, Iterable set2, List<List> common, List unfound,
-    {bool sameElement(a, b): equality, void checkElements(a, b)}) {
-  // TODO(johnniwinther): Avoid the quadratic cost here. Some ideas:
-  // - convert each set to a list and sort it first, then compare by walking
-  // both lists in parallel
-  // - map each element to a canonical object, create a map containing those
-  // mappings, use the mapped sets to compare (then operations like
-  // set.difference would work)
-  Set remaining = set2.toSet();
-  for (var element1 in set1) {
-    bool found = false;
-    var correspondingElement;
-    for (var element2 in remaining) {
-      if (sameElement(element1, element2)) {
-        if (checkElements != null) {
-          checkElements(element1, element2);
-        }
-        found = true;
-        correspondingElement = element2;
-        remaining.remove(element2);
-        break;
-      }
-    }
-    if (found) {
-      common.add([element1, correspondingElement]);
-    } else {
-      unfound.add(element1);
-    }
-  }
-  return remaining;
-}
-
-/// Check equivalence of the two iterables, [set1] and [set1], as sets using
-/// [elementEquivalence] to compute the pair-wise equivalence.
-///
-/// Uses [object1], [object2] and [property] to provide context for failures.
-bool checkSetEquivalence(var object1, var object2, String property,
-    Iterable set1, Iterable set2, bool sameElement(a, b),
-    {void onSameElement(a, b)}) {
-  List<List> common = <List>[];
-  List unfound = [];
-  Set remaining = computeSetDifference(set1, set2, common, unfound,
-      sameElement: sameElement, checkElements: onSameElement);
-  if (unfound.isNotEmpty || remaining.isNotEmpty) {
-    String message = "Set mismatch for `$property` on\n"
-        "$object1\n vs\n$object2:\n"
-        "Common:\n ${common.join('\n ')}\n"
-        "Unfound:\n ${unfound.join('\n ')}\n"
-        "Extra: \n ${remaining.join('\n ')}";
-    throw message;
-  }
-  return true;
-}
-
-/// Check equivalence of the two iterables, [set1] and [set1], as sets using
-/// [elementEquivalence] to compute the pair-wise equivalence.
-///
-/// Uses [object1], [object2] and [property] to provide context for failures.
-bool checkMapEquivalence(var object1, var object2, String property, Map map1,
-    Map map2, bool sameKey(a, b), bool sameValue(a, b),
-    {bool allowExtra: false}) {
-  List<List> common = <List>[];
-  List unfound = [];
-  Set extra = computeSetDifference(map1.keys, map2.keys, common, unfound,
-      sameElement: sameKey);
-  if (unfound.isNotEmpty || (!allowExtra && extra.isNotEmpty)) {
-    String message =
-        "Map key mismatch for `$property` on $object1 vs $object2: \n"
-        "Common:\n ${common.join('\n ')}\n"
-        "Unfound:\n ${unfound.join('\n ')}\n"
-        "Extra: \n ${extra.join('\n ')}";
-    throw message;
-  }
-  for (List pair in common) {
-    check(pair[0], pair[1], 'Map value for `$property`', map1[pair[0]],
-        map2[pair[1]], sameValue);
-  }
-  return true;
-}
-
-/// Checks the equivalence of the identity (but not properties) of [element1]
-/// and [element2].
-///
-/// Uses [object1], [object2] and [property] to provide context for failures.
-bool checkElementIdentities(Object object1, Object object2, String property,
-    Element element1, Element element2) {
-  if (identical(element1, element2)) return true;
-  return check(
-      object1, object2, property, element1, element2, areElementsEquivalent);
-}
-
-/// Checks the pair-wise equivalence of the identity (but not properties) of the
-/// elements in [list] and [list2].
-///
-/// Uses [object1], [object2] and [property] to provide context for failures.
-bool checkElementListIdentities(Object object1, Object object2, String property,
-    Iterable<Element> list1, Iterable<Element> list2) {
-  return checkListEquivalence(
-      object1, object2, property, list1, list2, checkElementIdentities);
-}
-
-/// Checks the equivalence of [type1] and [type2].
-///
-/// Uses [object1], [object2] and [property] to provide context for failures.
-bool checkTypes(Object object1, Object object2, String property,
-    ResolutionDartType type1, ResolutionDartType type2) {
-  if (identical(type1, type2)) return true;
-  if (type1 == null || type2 == null) {
-    return check(object1, object2, property, type1, type2);
-  } else {
-    return check(object1, object2, property, type1, type2,
-        (a, b) => const TypeEquivalence(const CheckStrategy()).visit(a, b));
-  }
-}
-
-/// Checks the pair-wise equivalence of the types in [list1] and [list2].
-///
-/// Uses [object1], [object2] and [property] to provide context for failures.
-bool checkTypeLists(Object object1, Object object2, String property,
-    List<DartType> list1, List<DartType> list2) {
-  return checkListEquivalence(
-      object1, object2, property, list1, list2, checkTypes);
-}
-
-/// Checks the equivalence of [exp1] and [exp2].
-///
-/// Uses [object1], [object2] and [property] to provide context for failures.
-bool checkConstants(Object object1, Object object2, String property,
-    ConstantExpression exp1, ConstantExpression exp2) {
-  if (identical(exp1, exp2)) return true;
-  if (exp1 == null || exp2 == null) {
-    return check(object1, object2, property, exp1, exp2);
-  } else {
-    return check(object1, object2, property, exp1, exp2,
-        (a, b) => const ConstantEquivalence(const CheckStrategy()).visit(a, b));
-  }
-}
-
-/// Checks the equivalence of [value1] and [value2].
-///
-/// Uses [object1], [object2] and [property] to provide context for failures.
-bool checkConstantValues(Object object1, Object object2, String property,
-    ConstantValue value1, ConstantValue value2) {
-  if (identical(value1, value2)) return true;
-  if (value1 == null || value2 == null) {
-    return check(object1, object2, property, value1, value2);
-  } else {
-    return check(
-        object1,
-        object2,
-        property,
-        value1,
-        value2,
-        (a, b) =>
-            const ConstantValueEquivalence(const CheckStrategy()).visit(a, b));
-  }
-}
-
-/// Checks the pair-wise equivalence of the constants in [list1] and [list2].
-///
-/// Uses [object1], [object2] and [property] to provide context for failures.
-bool checkConstantLists(Object object1, Object object2, String property,
-    List<ConstantExpression> list1, List<ConstantExpression> list2) {
-  return checkListEquivalence(
-      object1, object2, property, list1, list2, checkConstants);
-}
-
-/// Checks the pair-wise equivalence of the constants values in [list1] and
-/// [list2].
-///
-/// Uses [object1], [object2] and [property] to provide context for failures.
-bool checkConstantValueLists(Object object1, Object object2, String property,
-    List<ConstantValue> list1, List<ConstantValue> list2) {
-  return checkListEquivalence(
-      object1, object2, property, list1, list2, checkConstantValues);
-}
-
-/// Check member property equivalence between all members common to [compiler1]
-/// and [compiler2].
-void checkLoadedLibraryMembers(
-    Compiler compiler1,
-    Compiler compiler2,
-    bool hasProperty(Element member1),
-    void checkMemberProperties(Compiler compiler1, Element member1,
-        Compiler compiler2, Element member2,
-        {bool verbose}),
-    {bool verbose: false}) {
-  void checkMembers(Element member1, Element member2) {
-    if (member1.isClass && member2.isClass) {
-      ClassElement class1 = member1;
-      ClassElement class2 = member2;
-      if (!class1.isResolved) return;
-
-      if (hasProperty(member1)) {
-        if (areElementsEquivalent(member1, member2)) {
-          checkMemberProperties(compiler1, member1, compiler2, member2,
-              verbose: verbose);
-        }
-      }
-
-      class1.forEachLocalMember((m1) {
-        checkMembers(m1, class2.localLookup(m1.name));
-      });
-      ClassElement superclass1 = class1.superclass;
-      ClassElement superclass2 = class2.superclass;
-      while (superclass1 != null && superclass1.isUnnamedMixinApplication) {
-        for (ConstructorElement c1 in superclass1.constructors) {
-          checkMembers(c1, superclass2.lookupConstructor(c1.name));
-        }
-        superclass1 = superclass1.superclass;
-        superclass2 = superclass2.superclass;
-      }
-      return;
-    }
-
-    if (!hasProperty(member1)) {
-      return;
-    }
-
-    if (member2 == null) {
-      throw 'Missing member for ${member1}';
-    }
-
-    if (areElementsEquivalent(member1, member2)) {
-      checkMemberProperties(compiler1, member1, compiler2, member2,
-          verbose: verbose);
-    }
-  }
-
-  for (LibraryElement library1 in compiler1.libraryLoader.libraries) {
-    LibraryElement library2 =
-        compiler2.libraryLoader.lookupLibrary(library1.canonicalUri);
-    if (library2 != null) {
-      library1.forEachLocalMember((Element member1) {
-        checkMembers(member1, library2.localLookup(member1.name));
-      });
-    }
-  }
-}
-
-/// Check equivalence of all resolution impacts.
-void checkAllImpacts(Compiler compiler1, Compiler compiler2,
-    {bool verbose: false}) {
-  checkLoadedLibraryMembers(compiler1, compiler2, (Element member1) {
-    return compiler1.resolution.hasResolutionImpact(member1);
-  }, checkImpacts, verbose: verbose);
-}
-
-/// Check equivalence of resolution impact for [member1] and [member2].
-void checkImpacts(
-    Compiler compiler1, Element member1, Compiler compiler2, Element member2,
-    {bool verbose: false}) {
-  ResolutionImpact impact1 = compiler1.resolution.getResolutionImpact(member1);
-  ResolutionImpact impact2 = compiler2.resolution.getResolutionImpact(member2);
-
-  if (impact1 == null && impact2 == null) return;
-
-  if (verbose) {
-    print('Checking impacts for $member1 vs $member2');
-  }
-
-  if (impact1 == null) {
-    throw 'Missing impact for $member1. $member2 has $impact2';
-  }
-  if (impact2 == null) {
-    throw 'Missing impact for $member2. $member1 has $impact1';
-  }
-
-  testResolutionImpactEquivalence(impact1, impact2,
-      strategy: const CheckStrategy());
-}
-
-void checkSets(
-    Iterable set1, Iterable set2, String messagePrefix, bool sameElement(a, b),
-    {bool failOnUnfound: true,
-    bool failOnExtra: true,
-    bool verbose: false,
-    void onSameElement(a, b),
-    void onUnfoundElement(a),
-    void onExtraElement(b),
-    bool elementFilter(element),
-    elementConverter(element),
-    String elementToString(key): defaultToString}) {
-  if (elementFilter != null) {
-    set1 = set1.where(elementFilter);
-    set2 = set2.where(elementFilter);
-  }
-  if (elementConverter != null) {
-    set1 = set1.map(elementConverter);
-    set2 = set2.map(elementConverter);
-  }
-  List<List> common = <List>[];
-  List unfound = [];
-  Set remaining = computeSetDifference(set1, set2, common, unfound,
-      sameElement: sameElement, checkElements: onSameElement);
-  if (onUnfoundElement != null) {
-    unfound.forEach(onUnfoundElement);
-  }
-  if (onExtraElement != null) {
-    remaining.forEach(onExtraElement);
-  }
-  StringBuffer sb = new StringBuffer();
-  sb.write("$messagePrefix:");
-  if (verbose) {
-    sb.write("\n Common: \n");
-    for (List pair in common) {
-      var element1 = pair[0];
-      var element2 = pair[1];
-      sb.write("  [${elementToString(element1)},"
-          "${elementToString(element2)}]\n");
-    }
-  }
-  if (unfound.isNotEmpty || verbose) {
-    sb.write("\n Unfound:\n  ${unfound.map(elementToString).join('\n  ')}");
-  }
-  if (remaining.isNotEmpty || verbose) {
-    sb.write("\n Extra: \n  ${remaining.map(elementToString).join('\n  ')}");
-  }
-  String message = sb.toString();
-  if (unfound.isNotEmpty || remaining.isNotEmpty) {
-    if ((failOnUnfound && unfound.isNotEmpty) ||
-        (failOnExtra && remaining.isNotEmpty)) {
-      Expect.fail(message);
-    } else {
-      print(message);
-    }
-  } else if (verbose) {
-    print(message);
-  }
-}
-
-String defaultToString(obj) => '$obj';
-
-void checkMaps(Map map1, Map map2, String messagePrefix, bool sameKey(a, b),
-    bool sameValue(a, b),
-    {bool failOnUnfound: true,
-    bool failOnMismatch: true,
-    bool verbose: false,
-    String keyToString(key): defaultToString,
-    String valueToString(key): defaultToString}) {
-  List<List> common = <List>[];
-  List unfound = [];
-  List<List> mismatch = <List>[];
-  Set remaining = computeSetDifference(map1.keys, map2.keys, common, unfound,
-      sameElement: sameKey, checkElements: (k1, k2) {
-    var v1 = map1[k1];
-    var v2 = map2[k2];
-    if (!sameValue(v1, v2)) {
-      mismatch.add([k1, k2]);
-    }
-  });
-  StringBuffer sb = new StringBuffer();
-  sb.write("$messagePrefix:");
-  if (verbose) {
-    sb.write("\n Common: \n");
-    for (List pair in common) {
-      var k1 = pair[0];
-      var k2 = pair[1];
-      var v1 = map1[k1];
-      var v2 = map2[k2];
-      sb.write(" key1   =${keyToString(k1)}\n");
-      sb.write(" key2   =${keyToString(k2)}\n");
-      sb.write("  value1=${valueToString(v1)}\n");
-      sb.write("  value2=${valueToString(v2)}\n");
-    }
-  }
-  if (unfound.isNotEmpty || verbose) {
-    sb.write("\n Unfound: \n");
-    for (var k1 in unfound) {
-      var v1 = map1[k1];
-      sb.write(" key1   =${keyToString(k1)}\n");
-      sb.write("  value1=${valueToString(v1)}\n");
-    }
-  }
-  if (remaining.isNotEmpty || verbose) {
-    sb.write("\n Extra: \n");
-    for (var k2 in remaining) {
-      var v2 = map2[k2];
-      sb.write(" key2   =${keyToString(k2)}\n");
-      sb.write("  value2=${valueToString(v2)}\n");
-    }
-  }
-  if (mismatch.isNotEmpty || verbose) {
-    sb.write("\n Mismatch: \n");
-    for (List pair in mismatch) {
-      var k1 = pair[0];
-      var k2 = pair[1];
-      var v1 = map1[k1];
-      var v2 = map2[k2];
-      sb.write(" key1   =${keyToString(k1)}\n");
-      sb.write(" key2   =${keyToString(k2)}\n");
-      sb.write("  value1=${valueToString(v1)}\n");
-      sb.write("  value2=${valueToString(v2)}\n");
-    }
-  }
-  String message = sb.toString();
-  if (unfound.isNotEmpty || mismatch.isNotEmpty || remaining.isNotEmpty) {
-    if ((unfound.isNotEmpty && failOnUnfound) ||
-        (mismatch.isNotEmpty && failOnMismatch) ||
-        remaining.isNotEmpty) {
-      Expect.fail(message);
-    } else {
-      print(message);
-    }
-  } else if (verbose) {
-    print(message);
-  }
-}
-
-void checkAllResolvedAsts(Compiler compiler1, Compiler compiler2,
-    {bool verbose: false}) {
-  checkLoadedLibraryMembers(compiler1, compiler2, (Element member1) {
-    return member1 is ExecutableElement &&
-        compiler1.resolution.hasResolvedAst(member1);
-  }, checkResolvedAsts, verbose: verbose);
-}
-
-/// Check equivalence of [impact1] and [impact2].
-void checkResolvedAsts(
-    Compiler compiler1, Element member1, Compiler compiler2, Element member2,
-    {bool verbose: false}) {
-  if (!compiler2.serialization.isDeserialized(member2)) {
-    return;
-  }
-  ResolvedAst resolvedAst1 = compiler1.resolution.getResolvedAst(member1);
-  ResolvedAst resolvedAst2 = compiler2.serialization.getResolvedAst(member2);
-
-  if (resolvedAst1 == null || resolvedAst2 == null) return;
-
-  if (verbose) {
-    print('Checking resolved asts for $member1 vs $member2');
-  }
-
-  testResolvedAstEquivalence(resolvedAst1, resolvedAst2, const CheckStrategy());
-}
-
 /// Returns the test arguments for testing the [index]th skipped test. The
 /// [skip] count is used to check that [index] is a valid index.
 List<String> testSkipped(int index, int skip) {
@@ -634,201 +49,3 @@ List<String> testSegment(int index, int count, int skip) {
     return [segmentNumber(index - 1), segmentNumber(index)];
   }
 }
-
-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);
-  }
-}