Remove union type support from analyzer.

pkg/analyzer/test/generated/element_test.dart

Index: pkg/analyzer/test/generated/element_test.dart
diff --git a/pkg/analyzer/test/generated/element_test.dart b/pkg/analyzer/test/generated/element_test.dart
index 70509b37ccca629c54ee628cfadc83a8a2ee39d4..7dfddd7ff9a3203ddca818b167e4bbf3f73f6cb2 100644
--- a/pkg/analyzer/test/generated/element_test.dart
+++ b/pkg/analyzer/test/generated/element_test.dart
@@ -29,7 +29,6 @@ main() {
   runReflectiveTests(FunctionTypeImplTest);
   runReflectiveTests(InterfaceTypeImplTest);
   runReflectiveTests(TypeParameterTypeImplTest);
-  runReflectiveTests(UnionTypeImplTest);
   runReflectiveTests(VoidTypeImplTest);
   runReflectiveTests(ClassElementImplTest);
   runReflectiveTests(CompilationUnitElementImplTest);
@@ -3750,203 +3749,6 @@ class TypeParameterTypeImplTest extends EngineTestCase {
 }
 
 @reflectiveTest
-class UnionTypeImplTest extends EngineTestCase {
-  ClassElement _classA;
-
-  InterfaceType _typeA;
-
-  ClassElement _classB;
-
-  InterfaceType _typeB;
-
-  DartType _uA;
-
-  DartType _uB;
-
-  DartType _uAB;
-
-  DartType _uBA;
-
-  List<DartType> _us;
-
-  @override
-  void setUp() {
-    super.setUp();
-    _classA = ElementFactory.classElement2("A");
-    _typeA = _classA.type;
-    _classB = ElementFactory.classElement("B", _typeA);
-    _typeB = _classB.type;
-    _uA = UnionTypeImpl.union([_typeA]);
-    _uB = UnionTypeImpl.union([_typeB]);
-    _uAB = UnionTypeImpl.union([_typeA, _typeB]);
-    _uBA = UnionTypeImpl.union([_typeB, _typeA]);
-    _us = <DartType>[_uA, _uB, _uAB, _uBA];
-  }
-
-  void test_emptyUnionsNotAllowed() {
-    try {
-      UnionTypeImpl.union([]);
-    } on IllegalArgumentException {
-      return;
-    }
-    fail("Expected illegal argument exception.");
-  }
-
-  void test_equality_beingASubtypeOfAnElementIsNotSufficient() {
-    // Non-equal if some elements are different
-    expect(_uAB == _uA, isFalse);
-  }
-
-  void test_equality_insertionOrderDoesntMatter() {
-    // Insertion order doesn't matter, only sets of elements
-    expect(_uAB == _uBA, isTrue);
-    expect(_uBA == _uAB, isTrue);
-  }
-
-  void test_equality_reflexivity() {
-    for (DartType u in _us) {
-      expect(u == u, isTrue);
-    }
-  }
-
-  void test_equality_singletonsCollapse() {
-    expect(_typeA == _uA, isTrue);
-    expect(_uA == _typeA, isTrue);
-  }
-
-  void test_isMoreSpecificThan_allElementsOnLHSAreSubtypesOfSomeElementOnRHS() {
-    // Unions are subtypes when all elements are subtypes
-    expect(_uAB.isMoreSpecificThan(_uA), isTrue);
-    expect(_uAB.isMoreSpecificThan(_typeA), isTrue);
-  }
-
-  void test_isMoreSpecificThan_element() {
-    // Elements of union are sub types
-    expect(_typeA.isMoreSpecificThan(_uAB), isTrue);
-    expect(_typeB.isMoreSpecificThan(_uAB), isTrue);
-  }
-
-  void test_isMoreSpecificThan_notSubtypeOfAnyElement() {
-    // Types that are not subtypes of elements are not subtypes
-    expect(_typeA.isMoreSpecificThan(_uB), isFalse);
-  }
-
-  void test_isMoreSpecificThan_reflexivity() {
-    for (DartType u in _us) {
-      expect(u.isMoreSpecificThan(u), isTrue);
-    }
-  }
-
-  void test_isMoreSpecificThan_someElementOnLHSIsNotASubtypeOfAnyElementOnRHS() {
-    // Unions are subtypes when some element is a subtype
-    expect(_uAB.isMoreSpecificThan(_uB), isTrue);
-    expect(_uAB.isMoreSpecificThan(_typeB), isTrue);
-  }
-
-  void test_isMoreSpecificThan_subtypeOfSomeElement() {
-    // Subtypes of elements are sub types
-    expect(_typeB.isMoreSpecificThan(_uA), isTrue);
-  }
-
-  void test_isSubtypeOf_allElementsOnLHSAreSubtypesOfSomeElementOnRHS() {
-    // Unions are subtypes when all elements are subtypes
-    expect(_uAB.isSubtypeOf(_uA), isTrue);
-    expect(_uAB.isSubtypeOf(_typeA), isTrue);
-  }
-
-  void test_isSubtypeOf_element() {
-    // Elements of union are sub types
-    expect(_typeA.isSubtypeOf(_uAB), isTrue);
-    expect(_typeB.isSubtypeOf(_uAB), isTrue);
-  }
-
-  void test_isSubtypeOf_notSubtypeOfAnyElement() {
-    // Types that are not subtypes of elements are not subtypes
-    expect(_typeA.isSubtypeOf(_uB), isFalse);
-  }
-
-  void test_isSubtypeOf_reflexivity() {
-    for (DartType u in _us) {
-      expect(u.isSubtypeOf(u), isTrue);
-    }
-  }
-
-  void test_isSubtypeOf_someElementOnLHSIsNotASubtypeOfAnyElementOnRHS() {
-    // Unions are subtypes when some element is a subtype
-    expect(_uAB.isSubtypeOf(_uB), isTrue);
-    expect(_uAB.isSubtypeOf(_typeB), isTrue);
-  }
-
-  void test_isSubtypeOf_subtypeOfSomeElement() {
-    // Subtypes of elements are sub types
-    expect(_typeB.isSubtypeOf(_uA), isTrue);
-  }
-
-  void test_nestedUnionsCollapse() {
-    UnionType u = UnionTypeImpl.union([_uAB, _typeA]) as UnionType;
-    for (DartType t in u.elements) {
-      if (t is UnionType) {
-        fail("Expected only non-union types but found $t!");
-      }
-    }
-  }
-
-  void test_noLossage() {
-    UnionType u = UnionTypeImpl
-        .union([_typeA, _typeB, _typeB, _typeA, _typeB, _typeB]) as UnionType;
-    Set<DartType> elements = u.elements;
-    expect(elements.contains(_typeA), isTrue);
-    expect(elements.contains(_typeB), isTrue);
-    expect(elements.length == 2, isTrue);
-  }
-
-  void test_substitute() {
-    // Based on [InterfaceTypeImplTest.test_substitute_equal].
-    ClassElement classAE = ElementFactory.classElement2("A", ["E"]);
-    InterfaceType typeAE = classAE.type;
-    List<DartType> args = [_typeB];
-    List<DartType> params = [classAE.typeParameters[0].type];
-    DartType typeAESubbed = typeAE.substitute2(args, params);
-    expect(typeAE == typeAESubbed, isFalse);
-    expect(UnionTypeImpl.union([_typeA, typeAESubbed]),
-        UnionTypeImpl.union([_typeA, typeAE]).substitute2(args, params));
-  }
-
-  void test_toString_pair() {
-    String s = _uAB.toString();
-    expect(s == "{A,B}" || s == "{B,A}", isTrue);
-    expect(_uAB.displayName, s);
-  }
-
-  void test_toString_singleton() {
-    // Singleton unions collapse to the the single type.
-    expect(_uA.toString(), "A");
-  }
-
-  void test_unionTypeIsLessSpecificThan_function() {
-    // Based on
-    // [FunctionTypeImplTest.test_isAssignableTo_normalAndPositionalArgs].
-    ClassElement a = ElementFactory.classElement2("A");
-    FunctionType t =
-        ElementFactory.functionElement6("t", null, <ClassElement>[a]).type;
-    DartType uAT = UnionTypeImpl.union([_uA, t]);
-    expect(t.isMoreSpecificThan(uAT), isTrue);
-    expect(t.isMoreSpecificThan(_uAB), isFalse);
-  }
-
-  void test_unionTypeIsSuperTypeOf_function() {
-    // Based on
-    // [FunctionTypeImplTest.test_isAssignableTo_normalAndPositionalArgs].
-    ClassElement a = ElementFactory.classElement2("A");
-    FunctionType t =
-        ElementFactory.functionElement6("t", null, <ClassElement>[a]).type;
-    DartType uAT = UnionTypeImpl.union([_uA, t]);
-    expect(t.isSubtypeOf(uAT), isTrue);
-    expect(t.isSubtypeOf(_uAB), isFalse);
-  }
-}
-
-@reflectiveTest
 class VoidTypeImplTest extends EngineTestCase {
   /**
    * Reference {code VoidTypeImpl.getInstance()}.