Align strong-mode error codes with analyzer conv.

pkg/analyzer/lib/src/task/strong/info.dart

 // Copyright (c) 2015, 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.
 
 /// Defines static information collected by the type checker and used later by
 /// emitters to generate code.
 // TODO(jmesserly): this was ported from package:dev_compiler, and needs to be
 // refactored to fit into analyzer.
 library analyzer.src.task.strong.info;
 
 import 'package:analyzer/src/generated/ast.dart';
 import 'package:analyzer/src/generated/element.dart';
 import 'package:analyzer/src/generated/error.dart';
 
 import 'rules.dart';
 
+// A down cast due to a variable declaration to a ground type.  E.g.,
+//   T x = expr;
+// where T is ground.  We exclude non-ground types as these behave differently
+// compared to standard Dart.
+class AssignmentCast extends DownCast {
+  AssignmentCast(TypeRules rules, Expression expression, Cast cast)
+      : super._internal(rules, expression, cast);
+
+  @override
+  String get name => 'STRONG_MODE_ASSIGNMENT_CAST';
+
+  toErrorCode() => new HintCode(name, message);
+}
+
+// Coercion which casts one type to another
+class Cast extends Coercion {
+  Cast(DartType fromType, DartType toType) : super(fromType, toType);
+}
+
 // The abstract type of coercions mapping one type to another.
 // This class also exposes static builder functions which
 // check for errors and reduce redundant coercions to the identity.
 abstract class Coercion {
   final DartType fromType;
   final DartType toType;
   Coercion(this.fromType, this.toType);
   static Coercion cast(DartType fromT, DartType toT) => new Cast(fromT, toT);
+  static Coercion error() => new CoercionError();
   static Coercion identity(DartType type) => new Identity(type);
-  static Coercion error() => new CoercionError();
-}
-
-// Coercion which casts one type to another
-class Cast extends Coercion {
-  Cast(DartType fromType, DartType toType) : super(fromType, toType);
-}
-
-// The identity coercion
-class Identity extends Coercion {
-  Identity(DartType fromType) : super(fromType, fromType);
 }
 
 // The error coercion.  This coercion signals that a coercion
 // could not be generated.  The code generator should not see
 // these.
 class CoercionError extends Coercion {
   CoercionError() : super(null, null);
 }
 
-// TODO(jmesserly): this could use some refactoring. These are essentially
-// like ErrorCodes in analyzer, but we're including some details in our message.
-// Analyzer instead has template strings, and replaces '{0}' with the first
-// argument.
-abstract class StaticInfo {
-  /// AST Node this info is attached to.
-  AstNode get node;
-
-  // TODO(jmesserly): review the usage of error codes. We probably want our own,
-  // as well as some DDC specific [ErrorType]s.
-  ErrorCode toErrorCode();
-
-  // TODO(jmesserly): what convention to use here?
-  String get name => 'dev_compiler.$runtimeType';
-
-  List<Object> get arguments => [node];
-
-  AnalysisError toAnalysisError() {
-    int begin = node is AnnotatedNode
-        ? (node as AnnotatedNode).firstTokenAfterCommentAndMetadata.offset
-        : node.offset;
-    int length = node.end - begin;
-    var source = (node.root as CompilationUnit).element.source;
-    return new AnalysisError(source, begin, length, toErrorCode(), arguments);
-  }
-}
-
 /// Implicitly injected expression conversion.
 abstract class CoercionInfo extends StaticInfo {
+  static const String _propertyName = 'dev_compiler.src.info.CoercionInfo';
+
   final TypeRules rules;
 
   final Expression node;
 
-  DartType get convertedType;
-
   CoercionInfo(this.rules, this.node);
 
   DartType get baseType => rules.getStaticType(node);
+  DartType get convertedType;
+
+  String get message;
   DartType get staticType => convertedType;
 
-  String get message;
   toErrorCode() => new HintCode(name, message);
 
-  static const String _propertyName = 'dev_compiler.src.info.CoercionInfo';
-
   /// Gets the coercion info associated with this node.
   static CoercionInfo get(AstNode node) => node.getProperty(_propertyName);
 
   /// Sets the coercion info associated with this node.
   static CoercionInfo set(AstNode node, CoercionInfo info) {
     node.setProperty(_propertyName, info);
     return info;
   }
 }
 
 // Base class for all casts from base type to sub type.
 abstract class DownCast extends CoercionInfo {
   Cast _cast;
 
   DownCast._internal(TypeRules rules, Expression expression, this._cast)
       : super(rules, expression) {
     assert(_cast.toType != baseType &&
         _cast.fromType == baseType &&
         (baseType.isDynamic ||
             // Call methods make the following non-redundant
             _cast.toType.isSubtypeOf(baseType) ||
             baseType.isAssignableTo(_cast.toType)));
   }
 
+  @override List<Object> get arguments => [node, baseType, convertedType];
+
   Cast get cast => _cast;
 
   DartType get convertedType => _cast.toType;
-
-  @override List<Object> get arguments => [node, baseType, convertedType];
   @override String get message => '{0} ({1}) will need runtime check '
       'to cast to type {2}';
 
   // Factory to create correct DownCast variant.
   static StaticInfo create(TypeRules rules, Expression expression, Cast cast,
       {String reason}) {
     final fromT = cast.fromType;
     final toT = cast.toType;
 
     // toT <:_R fromT => to <: fromT
@@ skipping 58 matching lines @@
     if (parent is VariableDeclaration && (parent.initializer == expression)) {
       return new AssignmentCast(rules, expression, cast);
     }
 
     // Other casts
     return new DownCastImplicit(rules, expression, cast);
   }
 }
 
 //
-// Standard down casts.  These casts are implicitly injected by the compiler.
-//
-
-// A down cast from dynamic to T.
-class DynamicCast extends DownCast {
-  DynamicCast(TypeRules rules, Expression expression, Cast cast)
-      : super._internal(rules, expression, cast);
-
-  toErrorCode() => new HintCode(name, message);
-}
-
-// A down cast due to a variable declaration to a ground type.  E.g.,
-//   T x = expr;
-// where T is ground.  We exclude non-ground types as these behave differently
-// compared to standard Dart.
-class AssignmentCast extends DownCast {
-  AssignmentCast(TypeRules rules, Expression expression, Cast cast)
-      : super._internal(rules, expression, cast);
-
-  toErrorCode() => new HintCode(name, message);
-}
-
-//
-// Temporary "casts" of allocation sites - literals, constructor invocations,
-// and closures.  These should be handled by contextual inference.  In most
-// cases, inference will be sufficient, though in some it may unmask an actual
-// error: e.g.,
-//   List<int> l = [1, 2, 3]; // Inference succeeds
-//   List<String> l = [1, 2, 3]; // Inference reveals static type error
-// We're marking all as warnings for now.
-//
-// TODO(vsm,leafp): Remove this.
-class UninferredClosure extends DownCast {
-  UninferredClosure(TypeRules rules, FunctionExpression expression, Cast cast)
-      : super._internal(rules, expression, cast);
-
-  toErrorCode() => new StaticTypeWarningCode(name, message);
-}
-
-//
 // Implicit down casts.  These are only injected by the compiler by flag.
 //
-
 // A down cast to a non-ground type.  These behave differently from standard
 // Dart and may be more likely to fail at runtime.
 class DownCastComposite extends DownCast {
   DownCastComposite(TypeRules rules, Expression expression, Cast cast)
       : super._internal(rules, expression, cast);
 
+  @override
+  String get name => 'STRONG_MODE_DOWN_CAST_COMPOSITE';
+
   toErrorCode() => new StaticTypeWarningCode(name, message);
 }
 
 // A down cast to a non-ground type.  These behave differently from standard
 // Dart and may be more likely to fail at runtime.
 class DownCastImplicit extends DownCast {
   DownCastImplicit(TypeRules rules, Expression expression, Cast cast)
       : super._internal(rules, expression, cast);
 
+  @override
+  String get name => 'STRONG_MODE_DOWN_CAST_IMPLICIT';
+
   toErrorCode() => new HintCode(name, message);
 }
 
-// An inferred type for the wrapped expression, which may need to be
-// reified into the term
-abstract class InferredTypeBase extends CoercionInfo {
-  final DartType _type;
+//
+// Standard down casts.  These casts are implicitly injected by the compiler.
+//
 
-  InferredTypeBase._internal(TypeRules rules, Expression expression, this._type)
-      : super(rules, expression);
+// A down cast from dynamic to T.
+class DynamicCast extends DownCast {
+  DynamicCast(TypeRules rules, Expression expression, Cast cast)
+      : super._internal(rules, expression, cast);
 
-  DartType get type => _type;
-  DartType get convertedType => type;
-  @override String get message => '{0} has inferred type {1}';
-  @override List get arguments => [node, type];
+  @override
+  String get name => 'STRONG_MODE_DYNAMIC_CAST';
 
   toErrorCode() => new HintCode(name, message);
 }
 
+class DynamicInvoke extends CoercionInfo {
+  static const String _propertyName = 'dev_compiler.src.info.DynamicInvoke';
+
+  DynamicInvoke(TypeRules rules, Expression expression)
+      : super(rules, expression);
+  DartType get convertedType => rules.provider.dynamicType;
+  String get message => '{0} requires dynamic invoke';
+
+  @override
+  String get name => 'STRONG_MODE_DYNAMIC_INVOKE';
+
+  toErrorCode() => new HintCode(name, message);
+
+  /// Whether this [node] is the target of a dynamic operation.
+  static bool get(AstNode node) {
+    var value = node.getProperty(_propertyName);
+    return value != null ? value : false;
+  }
+
+  /// Sets whether this node is the target of a dynamic operation.
+  static bool set(AstNode node, bool value) {
+    // Free the storage for things that aren't dynamic.
+    if (value == false) value = null;
+    node.setProperty(_propertyName, value);
+    return value;
+  }
+}
+
+// The identity coercion
+class Identity extends Coercion {
+  Identity(DartType fromType) : super(fromType, fromType);
+}
+
 // Standard / unspecialized inferred type
 class InferredType extends InferredTypeBase {
   InferredType(TypeRules rules, Expression expression, DartType type)
       : super._internal(rules, expression, type);
 
+  @override
+  String get name => 'STRONG_MODE_INFERRED_TYPE';
+
   // Factory to create correct InferredType variant.
   static InferredTypeBase create(
       TypeRules rules, Expression expression, DartType type) {
     // Specialized inference:
     if (expression is Literal) {
       return new InferredTypeLiteral(rules, expression, type);
     }
     if (expression is InstanceCreationExpression) {
       return new InferredTypeAllocation(rules, expression, type);
     }
     if (expression is FunctionExpression) {
       return new InferredTypeClosure(rules, expression, type);
     }
     return new InferredType(rules, expression, type);
   }
 }
 
-// An infered type for a literal expression.
-class InferredTypeLiteral extends InferredTypeBase {
-  InferredTypeLiteral(TypeRules rules, Expression expression, DartType type)
-      : super._internal(rules, expression, type);
-}
-
 // An inferred type for a non-literal allocation site.
 class InferredTypeAllocation extends InferredTypeBase {
   InferredTypeAllocation(TypeRules rules, Expression expression, DartType type)
       : super._internal(rules, expression, type);
+
+  @override
+  String get name => 'STRONG_MODE_INFERRED_TYPE_ALLOCATION';
+}
+
+// An inferred type for the wrapped expression, which may need to be
+// reified into the term
+abstract class InferredTypeBase extends CoercionInfo {
+  final DartType _type;
+
+  InferredTypeBase._internal(TypeRules rules, Expression expression, this._type)
+      : super(rules, expression);
+
+  @override List get arguments => [node, type];
+  DartType get convertedType => type;
+  @override String get message => '{0} has inferred type {1}';
+  DartType get type => _type;
+
+  toErrorCode() => new HintCode(name, message);
 }
 
 // An inferred type for a closure expression
 class InferredTypeClosure extends InferredTypeBase {
   InferredTypeClosure(TypeRules rules, Expression expression, DartType type)
       : super._internal(rules, expression, type);
+
+  @override
+  String get name => 'STRONG_MODE_INFERRED_TYPE_CLOSURE';
 }
 
-class DynamicInvoke extends CoercionInfo {
-  DynamicInvoke(TypeRules rules, Expression expression)
-      : super(rules, expression);
+// An inferred type for a literal expression.
+class InferredTypeLiteral extends InferredTypeBase {
+  InferredTypeLiteral(TypeRules rules, Expression expression, DartType type)
+      : super._internal(rules, expression, type);
 
-  DartType get convertedType => rules.provider.dynamicType;
-  String get message => '{0} requires dynamic invoke';
-  toErrorCode() => new HintCode(name, message);
-
-  static const String _propertyName = 'dev_compiler.src.info.DynamicInvoke';
-
-  /// Whether this [node] is the target of a dynamic operation.
-  static bool get(AstNode node) {
-    var value = node.getProperty(_propertyName);
-    return value != null ? value : false;
-  }
-
-  /// Sets whether this node is the target of a dynamic operation.
-  static bool set(AstNode node, bool value) {
-    // Free the storage for things that aren't dynamic.
-    if (value == false) value = null;
-    node.setProperty(_propertyName, value);
-    return value;
-  }
+  @override
+  String get name => 'STRONG_MODE_INFERRED_TYPE_LITERAL';
 }
 
-abstract class StaticError extends StaticInfo {
-  final AstNode node;
+class InvalidFieldOverride extends InvalidOverride {
+  InvalidFieldOverride(AstNode node, ExecutableElement element,
+      InterfaceType base, DartType subType, DartType baseType)
+      : super(node, element, base, subType, baseType);
 
-  StaticError(this.node);
+  String get message => 'Field declaration {3}.{1} cannot be '
+      'overridden in {0}.';
 
-  String get message;
-
-  toErrorCode() => new CompileTimeErrorCode(name, message);
+  @override
+  String get name => 'STRONG_MODE_INVALID_FIELD_OVERRIDE';
 }
 
-class StaticTypeError extends StaticError {
-  final DartType baseType;
-  final DartType expectedType;
-  String reason = null;
+// Invalid override due to incompatible type.  I.e., the overridden signature
+// is not compatible with the original.
+class InvalidMethodOverride extends InvalidOverride {
+  InvalidMethodOverride(AstNode node, ExecutableElement element,
+      InterfaceType base, FunctionType subType, FunctionType baseType)
+      : super(node, element, base, subType, baseType);
 
-  StaticTypeError(TypeRules rules, Expression expression, this.expectedType,
-      {this.reason})
-      : baseType = rules.getStaticType(expression),
-        super(expression);
+  String get message => _messageHelper('Invalid override');
 
-  @override List<Object> get arguments => [node, baseType, expectedType];
-  @override String get message =>
-      'Type check failed: {0} ({1}) is not of type {2}' +
-          ((reason == null) ? '' : ' because $reason');
-}
-
-class InvalidVariableDeclaration extends StaticError {
-  final DartType expectedType;
-
-  InvalidVariableDeclaration(
-      TypeRules rules, AstNode declaration, this.expectedType)
-      : super(declaration);
-
-  @override List<Object> get arguments => [expectedType];
-  @override String get message => 'Type check failed: null is not of type {0}';
-}
-
-class InvalidParameterDeclaration extends StaticError {
-  final DartType expectedType;
-
-  InvalidParameterDeclaration(
-      TypeRules rules, FormalParameter declaration, this.expectedType)
-      : super(declaration);
-
-  @override List<Object> get arguments => [node, expectedType];
-  @override String get message => 'Type check failed: {0} is not of type {1}';
-}
-
-class NonGroundTypeCheckInfo extends StaticInfo {
-  final DartType type;
-  final AstNode node;
-
-  NonGroundTypeCheckInfo(this.node, this.type) {
-    assert(node is IsExpression || node is AsExpression);
-  }
-
-  @override List<Object> get arguments => [type];
-  String get message =>
-      "Runtime check on non-ground type {0} may throw StrongModeError";
-
-  toErrorCode() => new HintCode(name, message);
+  @override
+  String get name => 'STRONG_MODE_INVALID_METHOD_OVERRIDE';
 }
 
 // Invalid override of an instance member of a class.
 abstract class InvalidOverride extends StaticError {
   /// Member declaration with the invalid override.
   final ExecutableElement element;
 
   /// Type (class or interface) that provides the base declaration.
   final InterfaceType base;
 
   /// Actual type of the overridden member.
   final DartType subType;
 
   /// Actual type of the base member.
   final DartType baseType;
 
   /// Whether the error comes from combining a base class and an interface
   final bool fromBaseClass;
 
   /// Whether the error comes from a mixin (either overriding a base class or an
   /// interface declaration).
   final bool fromMixin;
 
   InvalidOverride(
       AstNode node, this.element, this.base, this.subType, this.baseType)
       : fromBaseClass = node is ExtendsClause,
         fromMixin = node.parent is WithClause,
         super(node);
 
-  ClassElement get parent => element.enclosingElement;
-
   @override List<Object> get arguments =>
       [parent.name, element.name, subType, base, baseType];
 
+  ClassElement get parent => element.enclosingElement;
+
   String _messageHelper(String errorName) {
     var lcErrorName = errorName.toLowerCase();
     var intro = fromBaseClass
         ? 'Base class introduces an $lcErrorName'
         : (fromMixin ? 'Mixin introduces an $lcErrorName' : errorName);
     return '$intro. The type of {0}.{1} ({2}) is not a '
         'subtype of {3}.{1} ({4}).';
   }
 }
 
-// Invalid override due to incompatible type.  I.e., the overridden signature
-// is not compatible with the original.
-class InvalidMethodOverride extends InvalidOverride {
-  InvalidMethodOverride(AstNode node, ExecutableElement element,
-      InterfaceType base, FunctionType subType, FunctionType baseType)
-      : super(node, element, base, subType, baseType);
+class InvalidParameterDeclaration extends StaticError {
+  final DartType expectedType;
 
-  String get message => _messageHelper('Invalid override');
-}
+  InvalidParameterDeclaration(
+      TypeRules rules, FormalParameter declaration, this.expectedType)
+      : super(declaration);
 
-class InvalidFieldOverride extends InvalidOverride {
-  InvalidFieldOverride(AstNode node, ExecutableElement element,
-      InterfaceType base, DartType subType, DartType baseType)
-      : super(node, element, base, subType, baseType);
-
-  String get message => 'Field declaration {3}.{1} cannot be '
-      'overridden in {0}.';
+  @override List<Object> get arguments => [node, expectedType];
+  @override String get message => 'Type check failed: {0} is not of type {1}';
+  @override
+  String get name => 'STRONG_MODE_INVALID_PARAMETER_DECLARATION';
 }
 
 /// Dart constructors have one weird quirk, illustrated with this example:
 ///
 ///     class Base {
 ///       var x;
 ///       Base() : x = print('Base.1') {
 ///         print('Base.2');
 ///       }
 ///     }
@@ skipping 16 matching lines @@
 ///
 /// Better to have `super` at the end, as required by the Dart style guide:
 /// <http://goo.gl/q1T4BB>
 ///
 /// For now this is the only pattern we support.
 class InvalidSuperInvocation extends StaticError {
   InvalidSuperInvocation(SuperConstructorInvocation node) : super(node);
 
   @override String get message => "super call must be last in an initializer "
       "list (see http://goo.gl/q1T4BB): {0}";
+
+  @override
+  String get name => 'STRONG_MODE_INVALID_SUPER_INVOCATION';
 }
+
+class InvalidVariableDeclaration extends StaticError {
+  final DartType expectedType;
+
+  InvalidVariableDeclaration(
+      TypeRules rules, AstNode declaration, this.expectedType)
+      : super(declaration);
+
+  @override List<Object> get arguments => [expectedType];
+  @override String get message => 'Type check failed: null is not of type {0}';
+
+  @override
+  String get name => 'STRONG_MODE_INVALID_VARIABLE_DECLARATION';
+}
+
+class NonGroundTypeCheckInfo extends StaticInfo {
+  final DartType type;
+  final AstNode node;
+
+  NonGroundTypeCheckInfo(this.node, this.type) {
+    assert(node is IsExpression || node is AsExpression);
+  }
+
+  @override List<Object> get arguments => [type];
+  String get message =>
+      "Runtime check on non-ground type {0} may throw StrongModeError";
+
+  @override
+  String get name => 'STRONG_MODE_NON_GROUND_TYPE_CHECK_INFO';
+
+  toErrorCode() => new HintCode(name, message);
+}
+
+abstract class StaticError extends StaticInfo {
+  final AstNode node;
+
+  StaticError(this.node);
+
+  String get message;
+
+  toErrorCode() => new CompileTimeErrorCode(name, message);
+}
+
+// TODO(jmesserly): this could use some refactoring. These are essentially
+// like ErrorCodes in analyzer, but we're including some details in our message.
+// Analyzer instead has template strings, and replaces '{0}' with the first
+// argument.
+abstract class StaticInfo {
+  List<Object> get arguments => [node];
+
+  String get name;
+
+  /// AST Node this info is attached to.
+  AstNode get node;
+
+  AnalysisError toAnalysisError() {
+    int begin = node is AnnotatedNode
+        ? (node as AnnotatedNode).firstTokenAfterCommentAndMetadata.offset
+        : node.offset;
+    int length = node.end - begin;
+    var source = (node.root as CompilationUnit).element.source;
+    return new AnalysisError(source, begin, length, toErrorCode(), arguments);
+  }
+
+  // TODO(jmesserly): review the usage of error codes. We probably want our own,
+  // as well as some DDC specific [ErrorType]s.
+  ErrorCode toErrorCode();
+}
+
+class StaticTypeError extends StaticError {
+  final DartType baseType;
+  final DartType expectedType;
+  String reason = null;
+
+  StaticTypeError(TypeRules rules, Expression expression, this.expectedType,
+      {this.reason})
+      : baseType = rules.getStaticType(expression),
+        super(expression);
+
+  @override List<Object> get arguments => [node, baseType, expectedType];
+  @override String get message =>
+      'Type check failed: {0} ({1}) is not of type {2}' +
+          ((reason == null) ? '' : ' because $reason');
+
+  @override
+  String get name => 'STRONG_MODE_STATIC_TYPE_ERROR';
+}
+
+//
+// Temporary "casts" of allocation sites - literals, constructor invocations,
+// and closures.  These should be handled by contextual inference.  In most
+// cases, inference will be sufficient, though in some it may unmask an actual
+// error: e.g.,
+//   List<int> l = [1, 2, 3]; // Inference succeeds
+//   List<String> l = [1, 2, 3]; // Inference reveals static type error
+// We're marking all as warnings for now.
+//
+// TODO(vsm,leafp): Remove this.
+class UninferredClosure extends DownCast {
+  UninferredClosure(TypeRules rules, FunctionExpression expression, Cast cast)
+      : super._internal(rules, expression, cast);
+
+  @override
+  String get name => 'STRONG_MODE_UNINFERRED_CLOSURE';
+
+  toErrorCode() => new StaticTypeWarningCode(name, message);
+}