Discard constructors and fields temporarily to get valid code compiling

Change-Id: If3e15a1f3164ee23a5e54e3a04b777de8e0189c9
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/108380
Reviewed-by: Konstantin Shcheglov <[email protected]>
Reviewed-by: Phil Quitslund <[email protected]>
Commit-Queue: Brian Wilkerson <[email protected]>

Author: bwilkerson

pkg/analyzer/lib/error/error.dart

@@ -135,6 +135,8 @@ const List<ErrorCode> errorCodeValues = const [
   CompileTimeErrorCode.EXTENDS_DEFERRED_CLASS,
   CompileTimeErrorCode.EXTENDS_DISALLOWED_CLASS,
   CompileTimeErrorCode.EXTENDS_NON_CLASS,
+  CompileTimeErrorCode.EXTENSION_DECLARES_CONSTRUCTOR,
+  CompileTimeErrorCode.EXTENSION_DECLARES_FIELD,
   CompileTimeErrorCode.EXTRA_POSITIONAL_ARGUMENTS,
   CompileTimeErrorCode.EXTRA_POSITIONAL_ARGUMENTS_COULD_BE_NAMED,
   CompileTimeErrorCode.FIELD_INITIALIZED_BY_MULTIPLE_INITIALIZERS,

pkg/analyzer/lib/src/error/codes.dart

@@ -1174,6 +1174,22 @@ class CompileTimeErrorCode extends ErrorCode {
           correction: "Try specifying a different superclass, or "
               "removing the extends clause.");
 
+  /**
+   * No parameters.
+   */
+  static const CompileTimeErrorCode EXTENSION_DECLARES_CONSTRUCTOR =
+      const CompileTimeErrorCode('EXTENSION_DECLARES_CONSTRUCTOR',
+          "Extensions can't declare constructors.",
+          correction: "Try removing the constructor declaration.");
+
+  /**
+   * No parameters.
+   */
+  static const CompileTimeErrorCode EXTENSION_DECLARES_FIELD =
+      const CompileTimeErrorCode(
+          'EXTENSION_DECLARES_FIELD', "Extensions can't declare fields.",
+          correction: "Try removing the field declaration.");
+
   /**
    * 12.14.2 Binding Actuals to Formals: It is a static warning if <i>m &lt;
    * h</i> or if <i>m &gt; n</i>.

pkg/analyzer/lib/src/fasta/ast_builder.dart

@@ -15,6 +15,7 @@ import 'package:analyzer/src/dart/ast/ast.dart'
         CompilationUnitImpl,
         ExtensionDeclarationImpl,
         MixinDeclarationImpl;
+import 'package:analyzer/src/error/codes.dart';
 import 'package:analyzer/src/fasta/error_converter.dart';
 import 'package:analyzer/src/generated/utilities_dart.dart';
 import 'package:front_end/src/fasta/messages.dart'
@@ -563,12 +564,6 @@ class AstBuilder extends StackListener {
     push(ast.awaitExpression(awaitKeyword, pop()));
   }
 
-  void endInvalidAwaitExpression(
-      Token awaitKeyword, Token endToken, MessageCode errorCode) {
-    debugEvent("InvalidAwaitExpression");
-    endAwaitExpression(awaitKeyword, endToken);
-  }
-
   @override
   void endBinaryExpression(Token operatorToken) {
     assert(operatorToken.isOperator ||
@@ -875,6 +870,15 @@ class AstBuilder extends StackListener {
           ast.simpleIdentifier(typeName.identifier.token, isDeclaration: true);
     }
 
+    if (extensionDeclaration != null) {
+      // TODO(brianwilkerson) Decide how to handle constructor and field
+      //  declarations within extensions. They are invalid, but we might want to
+      //  resolve them in order to get navigation, search, etc.
+      errorReporter.errorReporter.reportErrorForNode(
+          CompileTimeErrorCode.EXTENSION_DECLARES_CONSTRUCTOR,
+          name ?? returnType);
+      return;
+    }
     currentDeclarationMembers.add(ast.constructorDeclaration(
         comment,
         metadata,
@@ -917,6 +921,16 @@ class AstBuilder extends StackListener {
     Token covariantKeyword = covariantToken;
     List<Annotation> metadata = pop();
     Comment comment = _findComment(metadata, beginToken);
+    if (extensionDeclaration != null) {
+      // TODO(brianwilkerson) Decide how to handle constructor and field
+      //  declarations within extensions. They are invalid, but we might want to
+      //  resolve them in order to get navigation, search, etc.
+      for (VariableDeclaration variable in variables) {
+        errorReporter.errorReporter.reportErrorForNode(
+            CompileTimeErrorCode.EXTENSION_DECLARES_FIELD, variable.name);
+      }
+      return;
+    }
     currentDeclarationMembers.add(ast.fieldDeclaration2(
         comment: comment,
         metadata: metadata,
@@ -1338,6 +1352,12 @@ class AstBuilder extends StackListener {
     push(initializers);
   }
 
+  void endInvalidAwaitExpression(
+      Token awaitKeyword, Token endToken, MessageCode errorCode) {
+    debugEvent("InvalidAwaitExpression");
+    endAwaitExpression(awaitKeyword, endToken);
+  }
+
   @override
   void endLabeledStatement(int labelCount) {
     debugEvent("LabeledStatement");
@@ -1522,6 +1542,15 @@ class AstBuilder extends StackListener {
           initializers,
           redirectedConstructor,
           body);
+      if (extensionDeclaration != null) {
+        // TODO(brianwilkerson) Decide how to handle constructor and field
+        //  declarations within extensions. They are invalid, but we might want
+        //  to resolve them in order to get navigation, search, etc.
+        errorReporter.errorReporter.reportErrorForNode(
+            CompileTimeErrorCode.EXTENSION_DECLARES_CONSTRUCTOR,
+            name ?? prefixOrName);
+        return;
+      }
       currentDeclarationMembers.add(constructor);
       if (mixinDeclaration != null) {
         // TODO (danrubel): Report an error if this is a mixin declaration.

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

@@ -0,0 +1,46 @@
+// Copyright (c) 2019, 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.
+
+import 'package:analyzer/dart/analysis/features.dart';
+import 'package:analyzer/src/error/codes.dart';
+import 'package:analyzer/src/generated/engine.dart';
+import 'package:test_reflective_loader/test_reflective_loader.dart';
+
+import '../dart/resolution/driver_resolution.dart';
+
+main() {
+  defineReflectiveSuite(() {
+    defineReflectiveTests(ExtensionDeclaresConstructorTest);
+  });
+}
+
+@reflectiveTest
+class ExtensionDeclaresConstructorTest extends DriverResolutionTest {
+  @override
+  AnalysisOptionsImpl get analysisOptions => AnalysisOptionsImpl()
+    ..contextFeatures = new FeatureSet.forTesting(
+        sdkVersion: '2.3.0', additionalFeatures: [Feature.extension_methods]);
+
+  test_named() {
+    assertErrorsInCode('''
+extension E on String {
+  E.named() : super();
+}
+''', [error(CompileTimeErrorCode.EXTENSION_DECLARES_CONSTRUCTOR, 28, 5)]);
+  }
+
+  test_none() {
+    assertNoErrorsInCode('''
+extension E on String {}
+''');
+  }
+
+  test_unnamed() {
+    assertErrorsInCode('''
+extension E on String {
+  E() : super();
+}
+''', [error(CompileTimeErrorCode.EXTENSION_DECLARES_CONSTRUCTOR, 26, 1)]);
+  }
+}

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

@@ -0,0 +1,50 @@
+// Copyright (c) 2019, 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.
+
+import 'package:analyzer/dart/analysis/features.dart';
+import 'package:analyzer/src/error/codes.dart';
+import 'package:analyzer/src/generated/engine.dart';
+import 'package:test_reflective_loader/test_reflective_loader.dart';
+
+import '../dart/resolution/driver_resolution.dart';
+
+main() {
+  defineReflectiveSuite(() {
+    defineReflectiveTests(ExtensionDeclaresFieldTest);
+  });
+}
+
+@reflectiveTest
+class ExtensionDeclaresFieldTest extends DriverResolutionTest {
+  @override
+  AnalysisOptionsImpl get analysisOptions => AnalysisOptionsImpl()
+    ..contextFeatures = new FeatureSet.forTesting(
+        sdkVersion: '2.3.0', additionalFeatures: [Feature.extension_methods]);
+
+  test_multiple() {
+    assertErrorsInCode('''
+extension E on String {
+  String one, two, three;
+}
+''', [
+      error(CompileTimeErrorCode.EXTENSION_DECLARES_FIELD, 33, 3),
+      error(CompileTimeErrorCode.EXTENSION_DECLARES_FIELD, 38, 3),
+      error(CompileTimeErrorCode.EXTENSION_DECLARES_FIELD, 43, 5)
+    ]);
+  }
+
+  test_none() {
+    assertNoErrorsInCode('''
+extension E on String {}
+''');
+  }
+
+  test_one() {
+    assertErrorsInCode('''
+extension E on String {
+  String s;
+}
+''', [error(CompileTimeErrorCode.EXTENSION_DECLARES_FIELD, 33, 1)]);
+  }
+}

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

@@ -33,6 +33,9 @@ import 'equal_elements_in_const_set_test.dart' as equal_elements_in_const_set;
 import 'equal_keys_in_const_map_test.dart' as equal_keys_in_const_map;
 import 'expression_in_map_test.dart' as expression_in_map;
 import 'extends_non_class_test.dart' as extends_non_class;
+import 'extension_declares_constructor_test.dart'
+    as extension_declares_constructor;
+import 'extension_declares_field_test.dart' as extension_declares_field;
 import 'final_not_initialized_test.dart' as final_not_initialized;
 import 'implements_non_class_test.dart' as implements_non_class;
 import 'implicit_this_reference_in_initializer_test.dart'
@@ -197,6 +200,8 @@ main() {
     equal_keys_in_const_map.main();
     expression_in_map.main();
     extends_non_class.main();
+    extension_declares_constructor.main();
+    extension_declares_field.main();
     final_not_initialized.main();
     implements_non_class.main();
     implicit_this_reference_in_initializer.main();