Issue 51567. Implement constant equality as primitive equality

Bug: https://github.com/dart-lang/sdk/issues/51567
Change-Id: I7821598a761573519205b0ea06b13f433639282b
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/286241
Commit-Queue: Konstantin Shcheglov <scheglov@google.com>
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>

pkg/analyzer/lib/src/dart/constant/evaluation.dart

@@ -544,6 +544,7 @@ class ConstantVisitor extends UnifyingAstVisitor<DartObjectImpl> {
         _substitution = substitution {
     _dartObjectComputer = DartObjectComputer(
       typeSystem,
+      _library.featureSet,
       _errorReporter,
     );
   }
@@ -1566,11 +1567,12 @@ class ConstantVisitor extends UnifyingAstVisitor<DartObjectImpl> {
 /// class and for collecting errors during evaluation.
 class DartObjectComputer {
   final TypeSystemImpl _typeSystem;
+  final FeatureSet _featureSet;
 
   /// The error reporter that we are using to collect errors.
   final ErrorReporter _errorReporter;
 
-  DartObjectComputer(this._typeSystem, this._errorReporter);
+  DartObjectComputer(this._typeSystem, this._featureSet, this._errorReporter);
 
   DartObjectImpl? add(BinaryExpression node, DartObjectImpl? leftOperand,
       DartObjectImpl? rightOperand) {
@@ -1698,7 +1700,7 @@ class DartObjectComputer {
       DartObjectImpl? rightOperand) {
     if (leftOperand != null && rightOperand != null) {
       try {
-        return leftOperand.equalEqual(_typeSystem, rightOperand);
+        return leftOperand.equalEqual(_typeSystem, _featureSet, rightOperand);
       } on EvaluationException catch (exception) {
         _errorReporter.reportErrorForNode(exception.errorCode, node);
       }
@@ -1770,7 +1772,8 @@ class DartObjectComputer {
       DartObjectImpl? rightOperand) {
     if (leftOperand != null && rightOperand != null) {
       try {
-        return leftOperand.lazyEqualEqual(_typeSystem, rightOperand);
+        return leftOperand.lazyEqualEqual(
+            _typeSystem, _featureSet, rightOperand);
       } on EvaluationException catch (exception) {
         _errorReporter.reportErrorForNode(exception.errorCode, node);
       }
@@ -1878,7 +1881,7 @@ class DartObjectComputer {
       DartObjectImpl? rightOperand) {
     if (leftOperand != null && rightOperand != null) {
       try {
-        return leftOperand.notEqual(_typeSystem, rightOperand);
+        return leftOperand.notEqual(_typeSystem, _featureSet, rightOperand);
       } on EvaluationException catch (exception) {
         _errorReporter.reportErrorForNode(exception.errorCode, node);
       }

pkg/analyzer/lib/src/dart/constant/value.dart

@@ -429,7 +429,10 @@ class DartObjectImpl implements DartObject {
   /// Throws an [EvaluationException] if the operator is not appropriate for an
   /// object of this kind.
   DartObjectImpl equalEqual(
-      TypeSystemImpl typeSystem, DartObjectImpl rightOperand) {
+    TypeSystemImpl typeSystem,
+    FeatureSet featureSet,
+    DartObjectImpl rightOperand,
+  ) {
     if (isNull || rightOperand.isNull) {
       return DartObjectImpl(
         typeSystem,
@@ -439,12 +442,22 @@ class DartObjectImpl implements DartObject {
             : BoolState.FALSE_STATE,
       );
     }
-    if (isBoolNumStringOrNull) {
-      return DartObjectImpl(
-        typeSystem,
-        typeSystem.typeProvider.boolType,
-        state.equalEqual(typeSystem, rightOperand.state),
-      );
+    if (featureSet.isEnabled(Feature.patterns)) {
+      if (state is DoubleState || hasPrimitiveEquality(featureSet)) {
+        return DartObjectImpl(
+          typeSystem,
+          typeSystem.typeProvider.boolType,
+          state.equalEqual(typeSystem, rightOperand.state),
+        );
+      }
+    } else {
+      if (isBoolNumStringOrNull) {
+        return DartObjectImpl(
+          typeSystem,
+          typeSystem.typeProvider.boolType,
+          state.equalEqual(typeSystem, rightOperand.state),
+        );
+      }
     }
     throw EvaluationException(
         CompileTimeErrorCode.CONST_EVAL_TYPE_BOOL_NUM_STRING);
@@ -598,7 +611,10 @@ class DartObjectImpl implements DartObject {
   /// Throws an [EvaluationException] if the operator is not appropriate for an
   /// object of this kind.
   DartObjectImpl lazyEqualEqual(
-      TypeSystemImpl typeSystem, DartObjectImpl rightOperand) {
+    TypeSystemImpl typeSystem,
+    FeatureSet featureSet,
+    DartObjectImpl rightOperand,
+  ) {
     if (isNull || rightOperand.isNull) {
       return DartObjectImpl(
         typeSystem,
@@ -608,12 +624,22 @@ class DartObjectImpl implements DartObject {
             : BoolState.FALSE_STATE,
       );
     }
-    if (isBoolNumStringOrNull) {
-      return DartObjectImpl(
-        typeSystem,
-        typeSystem.typeProvider.boolType,
-        state.lazyEqualEqual(typeSystem, rightOperand.state),
-      );
+    if (featureSet.isEnabled(Feature.patterns)) {
+      if (state is DoubleState || hasPrimitiveEquality(featureSet)) {
+        return DartObjectImpl(
+          typeSystem,
+          typeSystem.typeProvider.boolType,
+          state.equalEqual(typeSystem, rightOperand.state),
+        );
+      }
+    } else {
+      if (isBoolNumStringOrNull) {
+        return DartObjectImpl(
+          typeSystem,
+          typeSystem.typeProvider.boolType,
+          state.equalEqual(typeSystem, rightOperand.state),
+        );
+      }
     }
     throw EvaluationException(
         CompileTimeErrorCode.CONST_EVAL_TYPE_BOOL_NUM_STRING);
@@ -739,8 +765,12 @@ class DartObjectImpl implements DartObject {
   /// Throws an [EvaluationException] if the operator is not appropriate for an
   /// object of this kind.
   DartObjectImpl notEqual(
-      TypeSystemImpl typeSystem, DartObjectImpl rightOperand) {
-    return equalEqual(typeSystem, rightOperand).logicalNot(typeSystem);
+    TypeSystemImpl typeSystem,
+    FeatureSet featureSet,
+    DartObjectImpl rightOperand,
+  ) {
+    return equalEqual(typeSystem, featureSet, rightOperand)
+        .logicalNot(typeSystem);
   }
 
   /// Return the result of converting this object to a 'String'.

pkg/analyzer/test/src/dart/constant/evaluation_test.dart

@@ -29,6 +29,166 @@ main() {
 @reflectiveTest
 class ConstantVisitorTest extends ConstantVisitorTestSupport
     with ConstantVisitorTestCases {
+  test_equalEqual_double_object() async {
+    await assertNoErrorsInCode('''
+const v = 1.2 == Object();
+''');
+    final value = _evaluateConstant('v');
+    assertDartObjectText(value, r'''
+bool false
+''');
+  }
+
+  test_equalEqual_int_int_false() async {
+    await assertNoErrorsInCode('''
+const v = 1 == 2;
+''');
+    final value = _evaluateConstant('v');
+    assertDartObjectText(value, r'''
+bool false
+''');
+  }
+
+  test_equalEqual_int_int_true() async {
+    await assertNoErrorsInCode('''
+const v = 1 == 1;
+''');
+    final value = _evaluateConstant('v');
+    assertDartObjectText(value, r'''
+bool true
+''');
+  }
+
+  test_equalEqual_int_null() async {
+    await assertNoErrorsInCode('''
+const int? a = 1;
+const v = a == null;
+''');
+    final value = _evaluateConstant('v');
+    assertDartObjectText(value, r'''
+bool false
+''');
+  }
+
+  test_equalEqual_int_object() async {
+    await assertNoErrorsInCode('''
+const v = 1 == Object();
+''');
+    final value = _evaluateConstant('v');
+    assertDartObjectText(value, r'''
+bool false
+''');
+  }
+
+  test_equalEqual_int_userClass() async {
+    await assertNoErrorsInCode('''
+class A {
+  const A();
+}
+
+const v = 1 == A();
+''');
+    final value = _evaluateConstant('v');
+    assertDartObjectText(value, r'''
+bool false
+''');
+  }
+
+  test_equalEqual_null_object() async {
+    await assertNoErrorsInCode('''
+const Object? a = null;
+const v = a == Object();
+''');
+    final value = _evaluateConstant('v');
+    assertDartObjectText(value, r'''
+bool false
+''');
+  }
+
+  test_equalEqual_string_object() async {
+    await assertNoErrorsInCode('''
+const v = 'foo' == Object();
+''');
+    final value = _evaluateConstant('v');
+    assertDartObjectText(value, r'''
+bool false
+''');
+  }
+
+  test_equalEqual_userClass_hasEqEq() async {
+    await assertErrorsInCode('''
+class A {
+  const A();
+  bool operator ==(other) => false;
+}
+
+const v = A() == 0;
+''', [
+      error(CompileTimeErrorCode.CONST_EVAL_TYPE_BOOL_NUM_STRING, 72, 8),
+    ]);
+    // TODO(scheglov) check the invalid value
+  }
+
+  test_equalEqual_userClass_hasHashCode() async {
+    await assertErrorsInCode('''
+class A {
+  const A();
+  int get hashCode => 0;
+}
+
+const v = A() == 0;
+''', [
+      error(CompileTimeErrorCode.CONST_EVAL_TYPE_BOOL_NUM_STRING, 61, 8),
+    ]);
+    // TODO(scheglov) check the invalid value
+  }
+
+  test_equalEqual_userClass_hasPrimitiveEquality_false() async {
+    await assertNoErrorsInCode('''
+class A {
+  final int f;
+  const A(this.f);
+}
+
+const v = A(0) == 0;
+''');
+    final value = _evaluateConstant('v');
+    assertDartObjectText(value, r'''
+bool false
+''');
+  }
+
+  test_equalEqual_userClass_hasPrimitiveEquality_language219() async {
+    await assertErrorsInCode('''
+// @dart = 2.19
+class A {
+  const A();
+}
+
+const v = A() == 0;
+''', [
+      error(CompileTimeErrorCode.CONST_EVAL_TYPE_BOOL_NUM_STRING, 52, 8),
+    ]);
+    _evaluateConstantOrNull('v', errorCodes: [
+      CompileTimeErrorCode.CONST_EVAL_TYPE_BOOL_NUM_STRING,
+    ]);
+  }
+
+  test_equalEqual_userClass_hasPrimitiveEquality_true() async {
+    await assertNoErrorsInCode('''
+class A {
+  final int f;
+  const A(this.f);
+}
+
+const v = A(0) == A(0);
+''');
+    final value = _evaluateConstant('v');
+    assertDartObjectText(value, r'''
+bool true
+''');
+  }
+
   test_hasPrimitiveEquality_bool() async {
     await assertNoErrorsInCode('''
 const v = true;
@@ -2314,6 +2474,19 @@ const a = const A<int?>();
     );
   }
 
+  test_assertInitializer_intInDoubleContext_true() async {
+    await assertNoErrorsInCode('''
+class A {
+  const A(double x): assert((x + 3) / 2 == 1.5);
+}
+const v = const A(0);
+''');
+    final value = _evaluateConstant('v');
+    assertDartObjectText(value, r'''
+A
+''');
+  }
+
   test_fieldInitializer_functionReference_withTypeParameter() async {
     await resolveTestCode('''
 void g<U>(U a) {}
@@ -2519,16 +2692,6 @@ const a = const A(1);
     );
   }
 
-  test_assertInitializer_intInDoubleContext_true() async {
-    await resolveTestCode('''
-class A {
-  const A(double x): assert((x + 3) / 2 == 1.5);
-}
-const a = const A(0);
-''');
-    _assertValidConstant('a');
-  }
-
   test_assertInitializer_simple_false() async {
     await resolveTestCode('''
 class A {

pkg/analyzer/test/src/dart/constant/value_test.dart

@@ -2,6 +2,7 @@
 // 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.
 
+import 'package:analyzer/dart/analysis/features.dart';
 import 'package:analyzer/dart/element/nullability_suffix.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/dart/element/type_provider.dart';
@@ -11,6 +12,7 @@ import 'package:test/test.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
 import '../../../generated/test_analysis_context.dart';
+import '../../../util/feature_sets.dart';
 
 main() {
   defineReflectiveSuite(() {
@@ -27,6 +29,7 @@ final Matcher throwsEvaluationException =
 class DartObjectImplTest {
   late final TypeProvider _typeProvider;
   late final TypeSystemImpl _typeSystem;
+  FeatureSet _featureSet = FeatureSets.latestWithExperiments;
 
   void setUp() {
     var analysisContext = TestAnalysisContext();
@@ -358,14 +361,29 @@ class DartObjectImplTest {
     _assertEqualEqual(_boolValue(false), _doubleValue(2.0), _doubleValue(4.0));
   }
 
+  void test_equalEqual_double_false_language219() {
+    _featureSet = FeatureSets.language_2_19;
+    _assertEqualEqual(_boolValue(false), _doubleValue(2.0), _doubleValue(4.0));
+  }
+
   void test_equalEqual_double_true() {
     _assertEqualEqual(_boolValue(true), _doubleValue(2.0), _doubleValue(2.0));
   }
 
+  void test_equalEqual_double_true_language219() {
+    _featureSet = FeatureSets.language_2_19;
+    _assertEqualEqual(_boolValue(true), _doubleValue(2.0), _doubleValue(2.0));
+  }
+
   void test_equalEqual_double_unknown() {
     _assertEqualEqual(_boolValue(null), _doubleValue(1.0), _doubleValue(null));
   }
 
+  void test_equalEqual_double_unknown_language219() {
+    _featureSet = FeatureSets.language_2_19;
+    _assertEqualEqual(_boolValue(null), _doubleValue(1.0), _doubleValue(null));
+  }
+
   void test_equalEqual_int_false() {
     _assertEqualEqual(_boolValue(false), _intValue(-5), _intValue(5));
   }
@@ -378,7 +396,8 @@ class DartObjectImplTest {
     _assertEqualEqual(_boolValue(null), _intValue(null), _intValue(3));
   }
 
-  void test_equalEqual_list_empty() {
+  void test_equalEqual_list_error_language219() {
+    _featureSet = FeatureSets.language_2_19;
     _assertEqualEqual(
       null,
       _listValue(_typeProvider.intType, []),
@@ -386,15 +405,16 @@ class DartObjectImplTest {
     );
   }
 
-  void test_equalEqual_list_false() {
+  void test_equalEqual_list_true() {
     _assertEqualEqual(
-      null,
+      _boolValue(true),
       _listValue(_typeProvider.intType, []),
       _listValue(_typeProvider.intType, []),
     );
   }
 
-  void test_equalEqual_map_empty() {
+  void test_equalEqual_map_error_language219() {
+    _featureSet = FeatureSets.language_2_19;
     _assertEqualEqual(
       null,
       _mapValue(_typeProvider.intType, _typeProvider.stringType, []),
@@ -402,9 +422,9 @@ class DartObjectImplTest {
     );
   }
 
-  void test_equalEqual_map_false() {
+  void test_equalEqual_map_true() {
     _assertEqualEqual(
-      null,
+      _boolValue(true),
       _mapValue(_typeProvider.intType, _typeProvider.stringType, []),
       _mapValue(_typeProvider.intType, _typeProvider.stringType, []),
     );
@@ -1582,11 +1602,21 @@ class DartObjectImplTest {
     _assertNotEqual(_boolValue(null), _boolValue(null), _boolValue(false));
   }
 
-  void test_notEqual_double_false() {
+  void test_notEqual_double_double_false() {
     _assertNotEqual(_boolValue(false), _doubleValue(2.0), _doubleValue(2.0));
   }
 
-  void test_notEqual_double_true() {
+  void test_notEqual_double_double_false_language219() {
+    _featureSet = FeatureSets.language_2_19;
+    _assertNotEqual(_boolValue(false), _doubleValue(2.0), _doubleValue(2.0));
+  }
+
+  void test_notEqual_double_double_true() {
+    _assertNotEqual(_boolValue(true), _doubleValue(2.0), _doubleValue(4.0));
+  }
+
+  void test_notEqual_double_double_true_language219() {
+    _featureSet = FeatureSets.language_2_19;
     _assertNotEqual(_boolValue(true), _doubleValue(2.0), _doubleValue(4.0));
   }
 
@@ -1594,6 +1624,11 @@ class DartObjectImplTest {
     _assertNotEqual(_boolValue(null), _doubleValue(1.0), _doubleValue(null));
   }
 
+  void test_notEqual_double_unknown_language219() {
+    _featureSet = FeatureSets.language_2_19;
+    _assertNotEqual(_boolValue(null), _doubleValue(1.0), _doubleValue(null));
+  }
+
   void test_notEqual_int_false() {
     _assertNotEqual(_boolValue(false), _intValue(5), _intValue(5));
   }
@@ -1996,10 +2031,10 @@ class DartObjectImplTest {
       DartObjectImpl? expected, DartObjectImpl left, DartObjectImpl right) {
     if (expected == null) {
       expect(() {
-        left.equalEqual(_typeSystem, right);
+        return left.equalEqual(_typeSystem, _featureSet, right);
       }, throwsEvaluationException);
     } else {
-      DartObjectImpl result = left.equalEqual(_typeSystem, right);
+      DartObjectImpl result = left.equalEqual(_typeSystem, _featureSet, right);
       expect(result, isNotNull);
       expect(result, expected);
     }
@@ -2189,10 +2224,10 @@ class DartObjectImplTest {
       DartObjectImpl? expected, DartObjectImpl left, DartObjectImpl right) {
     if (expected == null) {
       expect(() {
-        left.notEqual(_typeSystem, right);
+        left.notEqual(_typeSystem, _featureSet, right);
       }, throwsEvaluationException);
     } else {
-      DartObjectImpl result = left.notEqual(_typeSystem, right);
+      DartObjectImpl result = left.notEqual(_typeSystem, _featureSet, right);
       expect(result, isNotNull);
       expect(result, expected);
     }

pkg/analyzer/test/src/diagnostics/const_eval_type_bool_num_string_test.dart

@@ -22,6 +22,14 @@ const b = a == Object();
 ''');
   }
 
+  test_equal_double_object_language219() async {
+    await assertNoErrorsInCode(r'''
+// @dart = 2.19
+const a = 0.1;
+const b = a == Object();
+''');
+  }
+
   test_equal_int_object() async {
     await assertNoErrorsInCode(r'''
 const a = 0;
@@ -54,8 +62,48 @@ const b = a == Object();
 ''');
   }
 
-  test_equal_userClass_int() async {
+  test_equal_userClass_int_hasEqEq() async {
     await assertErrorsInCode(r'''
+class A {
+  const A();
+  bool operator ==(other) => false;
+}
+
+const a = A();
+const b = a == 0;
+''', [
+      error(CompileTimeErrorCode.CONST_EVAL_TYPE_BOOL_NUM_STRING, 87, 6),
+    ]);
+  }
+
+  test_equal_userClass_int_hasHashCode() async {
+    await assertErrorsInCode(r'''
+class A {
+  const A();
+  int get hashCode => 0;
+}
+
+const a = A();
+const b = a == 0;
+''', [
+      error(CompileTimeErrorCode.CONST_EVAL_TYPE_BOOL_NUM_STRING, 76, 6),
+    ]);
+  }
+
+  test_equal_userClass_int_hasPrimitiveEquality() async {
+    await assertNoErrorsInCode(r'''
+class A {
+  const A();
+}
+
+const a = A();
+const b = a == 0;
+''');
+  }
+
+  test_equal_userClass_int_language219() async {
+    await assertErrorsInCode(r'''
+// @dart = 2.19
 class A {
   const A();
 }
@@ -63,7 +111,7 @@ class A {
 const a = A();
 const b = a == 0;
 ''', [
-      error(CompileTimeErrorCode.CONST_EVAL_TYPE_BOOL_NUM_STRING, 51, 6),
+      error(CompileTimeErrorCode.CONST_EVAL_TYPE_BOOL_NUM_STRING, 67, 6),
     ]);
   }
 
@@ -74,6 +122,14 @@ const b = a != Object();
 ''');
   }
 
+  test_notEqual_double_object_language219() async {
+    await assertNoErrorsInCode(r'''
+// @dart = 2.19
+const a = 0.1;
+const b = a != Object();
+''');
+  }
+
   test_notEqual_int_object() async {
     await assertNoErrorsInCode(r'''
 const a = 0;
@@ -106,8 +162,48 @@ const b = a != Object();
 ''');
   }
 
-  test_notEqual_userClass_int() async {
+  test_notEqual_userClass_int_hasEqEq() async {
     await assertErrorsInCode(r'''
+class A {
+  const A();
+  bool operator ==(other) => false;
+}
+
+const a = A();
+const b = a != 0;
+''', [
+      error(CompileTimeErrorCode.CONST_EVAL_TYPE_BOOL_NUM_STRING, 87, 6),
+    ]);
+  }
+
+  test_notEqual_userClass_int_hasHashCode() async {
+    await assertErrorsInCode(r'''
+class A {
+  const A();
+  int get hashCode => 0;
+}
+
+const a = A();
+const b = a != 0;
+''', [
+      error(CompileTimeErrorCode.CONST_EVAL_TYPE_BOOL_NUM_STRING, 76, 6),
+    ]);
+  }
+
+  test_notEqual_userClass_int_hasPrimitiveEquality() async {
+    await assertNoErrorsInCode(r'''
+class A {
+  const A();
+}
+
+const a = A();
+const b = a != 0;
+''');
+  }
+
+  test_notEqual_userClass_int_language219() async {
+    await assertErrorsInCode(r'''
+// @dart = 2.19
 class A {
   const A();
 }
@@ -115,7 +211,7 @@ class A {
 const a = A();
 const b = a != 0;
 ''', [
-      error(CompileTimeErrorCode.CONST_EVAL_TYPE_BOOL_NUM_STRING, 51, 6),
+      error(CompileTimeErrorCode.CONST_EVAL_TYPE_BOOL_NUM_STRING, 67, 6),
     ]);
   }
 }

tests/language/patterns/invalid_const_pattern_binary_test.dart

@@ -177,8 +177,6 @@ method<T>(o) {
     // [analyzer] SYNTACTIC_ERROR.INVALID_CONSTANT_CONST_PREFIX
     // [cfe] The expression can't be prefixed by 'const' to form a constant pattern.
     case const Object() == 2: // Error
-    //         ^^^^^^^^^^^^^
-    // [analyzer] COMPILE_TIME_ERROR.CONST_EVAL_TYPE_BOOL_NUM_STRING
     //                ^
     // [analyzer] SYNTACTIC_ERROR.INVALID_CONSTANT_CONST_PREFIX
     // [cfe] The expression can't be prefixed by 'const' to form a constant pattern.
@@ -243,4 +241,4 @@ method<T>(o) {
     // [analyzer] COMPILE_TIME_ERROR.CONSTANT_PATTERN_WITH_NON_CONSTANT_EXPRESSION
     // [cfe] Not a constant expression.
   }
-}
+}