Refactor strong mode to use standard Analyzer errors

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

Index: pkg/analyzer/lib/src/task/strong/info.dart
diff --git a/pkg/analyzer/lib/src/task/strong/info.dart b/pkg/analyzer/lib/src/task/strong/info.dart
deleted file mode 100644
index 5b147e745c7401e30a9db0f1268a0064d4874b49..0000000000000000000000000000000000000000
--- a/pkg/analyzer/lib/src/task/strong/info.dart
+++ /dev/null
@@ -1,468 +0,0 @@
-// 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/dart/ast/ast.dart';
-import 'package:analyzer/dart/element/element.dart';
-import 'package:analyzer/dart/element/type.dart';
-import 'package:analyzer/src/dart/element/type.dart';
-import 'package:analyzer/src/generated/error.dart';
-import 'package:analyzer/src/generated/engine.dart' show AnalysisOptionsImpl;
-import 'package:analyzer/src/generated/type_system.dart';
-
-/// Implicitly injected expression conversion.
-abstract class CoercionInfo extends StaticInfo {
-  static const String _propertyName = 'dev_compiler.src.info.CoercionInfo';
-
-  final Expression node;
-
-  CoercionInfo(this.node);
-
-  DartType get baseType => node.staticType ?? DynamicTypeImpl.instance;
-  DartType get convertedType;
-
-  String get message;
-  DartType get staticType => convertedType;
-
-  toErrorCode() => new HintCode(name, message);
-
-  /// 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;
-  }
-}
-
-/// Implicit casts from base type to sub type.
-class DownCast extends CoercionInfo {
-  final DartType _fromType;
-  final DartType _toType;
-  ErrorCode _errorCode;
-
-  DownCast._(
-      Expression expression, this._fromType, this._toType, this._errorCode)
-      : super(expression);
-
-  @override
-  List<Object> get arguments => [baseType, convertedType];
-
-  /// The type being cast from.
-  ///
-  /// This is usually the static type of the associated expression, but may not
-  /// be if the cast is attached to a variable in a for-in loop.
-  @override
-  DartType get baseType => _fromType;
-
-  @override
-  DartType get convertedType => _toType;
-
-  @override
-  String get message => _message;
-
-  @override
-  String get name => _errorCode.name;
-
-  @override
-  toErrorCode() => _errorCode;
-
-  static const String _message = 'Unsound implicit cast from {0} to {1}';
-
-  /// Factory to create correct DownCast variant.
-  static StaticInfo create(StrongTypeSystemImpl rules, Expression expression,
-      DartType fromType, DartType toType, AnalysisOptionsImpl options) {
-    // toT <:_R fromT => to <: fromT
-    // NB: classes with call methods are subtypes of function
-    // types, but the function type is not assignable to the class
-    assert(toType.isSubtypeOf(fromType) || fromType.isAssignableTo(toType));
-
-    // Inference "casts":
-    if (expression is Literal || expression is FunctionExpression) {
-      // fromT should be an exact type - this will almost certainly fail at
-      // runtime.
-      return new StaticTypeError(expression, toType);
-    }
-
-    if (expression is InstanceCreationExpression) {
-      ConstructorElement e = expression.staticElement;
-      if (e == null || !e.isFactory) {
-        // fromT should be an exact type - this will almost certainly fail at
-        // runtime.
-        return new StaticTypeError(expression, toType);
-      }
-    }
-
-    if (StaticInfo.isKnownFunction(expression)) {
-      return new StaticTypeError(expression, toType);
-    }
-
-    // TODO(vsm): Change this to an assert when we have generic methods and
-    // fix TypeRules._coerceTo to disallow implicit sideways casts.
-    bool downCastComposite = false;
-    if (!rules.isSubtypeOf(toType, fromType)) {
-      assert(toType.isSubtypeOf(fromType) || fromType.isAssignableTo(toType));
-      downCastComposite = true;
-    }
-
-    // Composite cast: these are more likely to fail.
-    if (!rules.isGroundType(toType)) {
-      // This cast is (probably) due to our different treatment of dynamic.
-      // It may be more likely to fail at runtime.
-      if (fromType is InterfaceType) {
-        // For class types, we'd like to allow non-generic down casts, e.g.,
-        // Iterable<T> to List<T>.  The intuition here is that raw (generic)
-        // casts are problematic, and we should complain about those.
-        var typeArgs = fromType.typeArguments;
-        downCastComposite =
-            typeArgs.isEmpty || typeArgs.any((t) => t.isDynamic);
-      } else {
-        downCastComposite = true;
-      }
-    }
-
-    var parent = expression.parent;
-    String name;
-    if (downCastComposite) {
-      name = 'STRONG_MODE_DOWN_CAST_COMPOSITE';
-    } else if (fromType.isDynamic) {
-      name = 'STRONG_MODE_DYNAMIC_CAST';
-    } else if (parent is VariableDeclaration &&
-        parent.initializer == expression) {
-      name = 'STRONG_MODE_ASSIGNMENT_CAST';
-    } else {
-      name = 'STRONG_MODE_DOWN_CAST_IMPLICIT';
-    }
-
-    // For the remaining cases, we allow implicit casts by default.
-    // However this can be disabled with an option.
-    ErrorCode errorCode;
-    if (!options.implicitCasts) {
-      errorCode = new CompileTimeErrorCode(name, _message);
-    } else if (downCastComposite) {
-      errorCode = new StaticWarningCode(name, _message);
-    } else {
-      errorCode = new HintCode(name, _message);
-    }
-    return new DownCast._(expression, fromType, toType, errorCode);
-  }
-}
-
-class DynamicInvoke extends CoercionInfo {
-  static const String _propertyName = 'dev_compiler.src.info.DynamicInvoke';
-
-  DynamicInvoke(Expression expression) : super(expression);
-  DartType get convertedType => DynamicTypeImpl.instance;
-  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) => node.getProperty(_propertyName) ?? 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;
-  }
-}
-
-/// A marker for an inferred type.
-class InferredType extends CoercionInfo {
-  @override
-  final String name;
-
-  final DartType type;
-
-  InferredType(Expression expression, this.type, this.name) : super(expression);
-
-  /// Factory to create correct InferredType variant.
-  static InferredType create(
-      TypeSystem rules, Expression expression, DartType type) {
-    // Specialized inference:
-    String name;
-    if (expression is Literal) {
-      name = 'STRONG_MODE_INFERRED_TYPE_LITERAL';
-    } else if (expression is InstanceCreationExpression) {
-      name = 'STRONG_MODE_INFERRED_TYPE_ALLOCATION';
-    } else if (expression is FunctionExpression) {
-      name = 'STRONG_MODE_INFERRED_TYPE_CLOSURE';
-    } else {
-      name = 'STRONG_MODE_INFERRED_TYPE';
-    }
-    return new InferredType(expression, type, name);
-  }
-
-  @override
-  List get arguments => [node, type];
-
-  DartType get convertedType => type;
-
-  @override
-  String get message => '{0} has inferred type {1}';
-
-  toErrorCode() => new HintCode(name, message);
-}
-
-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
-  String get name => 'STRONG_MODE_INVALID_FIELD_OVERRIDE';
-}
-
-/// 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);
-
-  String get message => _messageHelper('Invalid override');
-
-  @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);
-
-  @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}).';
-  }
-}
-
-class InvalidParameterDeclaration extends StaticError {
-  final DartType expectedType;
-
-  InvalidParameterDeclaration(
-      TypeSystem 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}';
-  @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');
-///       }
-///     }
-///
-///     class Derived extends Base {
-///       var y, z;
-///       Derived()
-///           : y = print('Derived.1'),
-///             super(),
-///             z = print('Derived.2') {
-///         print('Derived.3');
-///       }
-///     }
-///
-/// The order will be Derived.1, Base.1, Derived.2, Base.2, Derived.3; this
-/// ordering preserves the invariant that code can't observe uninitialized
-/// state, however it results in super constructor body not being run
-/// immediately after super initializers. Normally this isn't observable, but it
-/// could be if initializers have side effects.
-///
-/// Better to have `super` at the end, as required by the Dart style guide:
-/// <https://goo.gl/EY6hDP>
-///
-/// 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 https://goo.gl/EY6hDP): {0}";
-
-  @override
-  String get name => 'STRONG_MODE_INVALID_SUPER_INVOCATION';
-}
-
-class InvalidVariableDeclaration extends StaticError {
-  final DartType expectedType;
-
-  InvalidVariableDeclaration(
-      TypeSystem 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 {
-  /// Strong-mode error code names.
-  ///
-  /// Used for error code configuration validation in an analysis options file.
-  static const List<String> names = const [
-    //
-    // Manually populated.
-    //
-    'STRONG_MODE_ASSIGNMENT_CAST',
-    'STRONG_MODE_DOWN_CAST_COMPOSITE',
-    'STRONG_MODE_DOWN_CAST_IMPLICIT',
-    'STRONG_MODE_DYNAMIC_CAST',
-    'STRONG_MODE_DYNAMIC_INVOKE',
-    'STRONG_MODE_INFERRED_TYPE',
-    'STRONG_MODE_INFERRED_TYPE_ALLOCATION',
-    'STRONG_MODE_INFERRED_TYPE_CLOSURE',
-    'STRONG_MODE_INFERRED_TYPE_LITERAL',
-    'STRONG_MODE_INVALID_FIELD_OVERRIDE',
-    'STRONG_MODE_INVALID_METHOD_OVERRIDE',
-    'STRONG_MODE_INVALID_PARAMETER_DECLARATION',
-    'STRONG_MODE_INVALID_SUPER_INVOCATION',
-    'STRONG_MODE_INVALID_VARIABLE_DECLARATION',
-    'STRONG_MODE_NON_GROUND_TYPE_CHECK_INFO',
-    'STRONG_MODE_STATIC_TYPE_ERROR',
-  ];
-
-  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();
-
-  static bool isKnownFunction(Expression expression) {
-    Element element = null;
-    if (expression is FunctionExpression) {
-      return true;
-    } else if (expression is PropertyAccess) {
-      element = expression.propertyName.staticElement;
-    } else if (expression is Identifier) {
-      element = expression.staticElement;
-    }
-    // First class functions and static methods, where we know the original
-    // declaration, will have an exact type, so we know a downcast will fail.
-    return element is FunctionElement ||
-        element is MethodElement && element.isStatic;
-  }
-}
-
-class StaticTypeError extends StaticError {
-  final DartType baseType;
-  final DartType expectedType;
-
-  StaticTypeError(Expression expression, this.expectedType)
-      : baseType = expression.staticType ?? DynamicTypeImpl.instance,
-        super(expression);
-
-  @override
-  List<Object> get arguments => [node, baseType, expectedType];
-  @override
-  String get message => 'Type check failed: {0} ({1}) is not of type {2}';
-
-  @override
-  String get name => 'STRONG_MODE_STATIC_TYPE_ERROR';
-}