pkg/analyzer/lib/src/generated/static_type_analyzer.dart - sdk.git - Git at Google

 // Copyright (c) 2014, 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/ast/ast.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/src/dart/ast/ast.dart';
 import 'package:analyzer/src/dart/ast/extensions.dart';
 import 'package:analyzer/src/dart/element/type_provider.dart';
 import 'package:analyzer/src/dart/element/type_system.dart';
 import 'package:analyzer/src/dart/resolver/invocation_inference_helper.dart';
 import 'package:analyzer/src/generated/resolver.dart';

 /// Instances of the class `StaticTypeAnalyzer` perform two type-related tasks. First, they
 /// compute the static type of every expression. Second, they look for any static type errors or
 /// warnings that might need to be generated. The requirements for the type analyzer are:
 /// <ol>
 /// * Every element that refers to types should be fully populated.
 /// * Every node representing an expression should be resolved to the Type of the expression.
 /// </ol>
 class StaticTypeAnalyzer {
   /// The resolver driving the resolution and type analysis.
   final ResolverVisitor _resolver;

   final InvocationInferenceHelper _inferenceHelper;

   /// The object providing access to the types defined by the language.
   late TypeProviderImpl _typeProvider;

   /// The type system in use for static type analysis.
   late TypeSystemImpl _typeSystem;

   /// The type representing the type 'dynamic'.
   late DartType _dynamicType;

   /// Initialize a newly created static type analyzer to analyze types for the
   /// [_resolver] based on the
   ///
   /// @param resolver the resolver driving this participant
   StaticTypeAnalyzer(this._resolver)
       : _inferenceHelper = _resolver.inferenceHelper {
     _typeProvider = _resolver.typeProvider;
     _typeSystem = _resolver.typeSystem;
     _dynamicType = _typeProvider.dynamicType;
   }

   /// The Dart Language Specification, 12.5: <blockquote>The static type of a string literal is
   /// `String`.</blockquote>
   void visitAdjacentStrings(covariant AdjacentStringsImpl node,
       {required DartType? contextType}) {
     _inferenceHelper.recordStaticType(node, _typeProvider.stringType,
         contextType: contextType);
   }

   /// The Dart Language Specification, 12.32: <blockquote>... the cast expression <i>e as T</i> ...
   ///
   /// It is a static warning if <i>T</i> does not denote a type available in the current lexical
   /// scope.
   ///
   /// The static type of a cast expression <i>e as T</i> is <i>T</i>.</blockquote>
   void visitAsExpression(covariant AsExpressionImpl node,
       {required DartType? contextType}) {
     _inferenceHelper.recordStaticType(node, _getType(node.type),
         contextType: contextType);
   }

   /// The Dart Language Specification, 16.29 (Await Expressions):
   ///
   ///   The static type of [the expression "await e"] is flatten(T) where T is
   ///   the static type of e.
   void visitAwaitExpression(covariant AwaitExpressionImpl node,
       {required DartType? contextType}) {
     var resultType = node.expression.typeOrThrow;
     resultType = _typeSystem.flatten(resultType);
     _inferenceHelper.recordStaticType(node, resultType,
         contextType: contextType);
   }

   /// The Dart Language Specification, 12.4: <blockquote>The static type of a boolean literal is
   /// bool.</blockquote>
   void visitBooleanLiteral(covariant BooleanLiteralImpl node,
       {required DartType? contextType}) {
     _inferenceHelper.recordStaticType(node, _typeProvider.boolType,
         contextType: contextType);
   }

   /// The Dart Language Specification, 12.15.2: <blockquote>A cascaded method invocation expression
   /// of the form <i>e..suffix</i> is equivalent to the expression <i>(t) {t.suffix; return
   /// t;}(e)</i>.</blockquote>
   void visitCascadeExpression(covariant CascadeExpressionImpl node,
       {required DartType? contextType}) {
     _inferenceHelper.recordStaticType(node, node.target.typeOrThrow,
         contextType: contextType);
   }

   /// The Dart Language Specification, 12.19: <blockquote> ... a conditional expression <i>c</i> of
   /// the form <i>e<sub>1</sub> ? e<sub>2</sub> : e<sub>3</sub></i> ...
   ///
   /// It is a static type warning if the type of e<sub>1</sub> may not be assigned to `bool`.
   ///
   /// The static type of <i>c</i> is the least upper bound of the static type of <i>e<sub>2</sub></i>
   /// and the static type of <i>e<sub>3</sub></i>.</blockquote>
   void visitConditionalExpression(covariant ConditionalExpressionImpl node,
       {required DartType? contextType}) {
     _analyzeLeastUpperBound(node, node.thenExpression, node.elseExpression,
         contextType: contextType);
   }

   /// The Dart Language Specification, 12.3: <blockquote>The static type of a literal double is
   /// double.</blockquote>
   void visitDoubleLiteral(covariant DoubleLiteralImpl node,
       {required DartType? contextType}) {
     _inferenceHelper.recordStaticType(node, _typeProvider.doubleType,
         contextType: contextType);
   }

   void visitExtensionOverride(ExtensionOverride node) {
     assert(false,
         'Resolver should call extensionResolver.resolveOverride directly');
   }

   /// The Dart Language Specification, 12.9: <blockquote>The static type of a function literal of the
   /// form <i>(T<sub>1</sub> a<sub>1</sub>, &hellip;, T<sub>n</sub> a<sub>n</sub>, [T<sub>n+1</sub>
   /// x<sub>n+1</sub> = d1, &hellip;, T<sub>n+k</sub> x<sub>n+k</sub> = dk]) => e</i> is
   /// <i>(T<sub>1</sub>, &hellip;, Tn, [T<sub>n+1</sub> x<sub>n+1</sub>, &hellip;, T<sub>n+k</sub>
   /// x<sub>n+k</sub>]) &rarr; T<sub>0</sub></i>, where <i>T<sub>0</sub></i> is the static type of
   /// <i>e</i>. In any case where <i>T<sub>i</sub>, 1 &lt;= i &lt;= n</i>, is not specified, it is
   /// considered to have been specified as dynamic.
   ///
   /// The static type of a function literal of the form <i>(T<sub>1</sub> a<sub>1</sub>, &hellip;,
   /// T<sub>n</sub> a<sub>n</sub>, {T<sub>n+1</sub> x<sub>n+1</sub> : d1, &hellip;, T<sub>n+k</sub>
   /// x<sub>n+k</sub> : dk}) => e</i> is <i>(T<sub>1</sub>, &hellip;, T<sub>n</sub>, {T<sub>n+1</sub>
   /// x<sub>n+1</sub>, &hellip;, T<sub>n+k</sub> x<sub>n+k</sub>}) &rarr; T<sub>0</sub></i>, where
   /// <i>T<sub>0</sub></i> is the static type of <i>e</i>. In any case where <i>T<sub>i</sub>, 1
   /// &lt;= i &lt;= n</i>, is not specified, it is considered to have been specified as dynamic.
   ///
   /// The static type of a function literal of the form <i>(T<sub>1</sub> a<sub>1</sub>, &hellip;,
   /// T<sub>n</sub> a<sub>n</sub>, [T<sub>n+1</sub> x<sub>n+1</sub> = d1, &hellip;, T<sub>n+k</sub>
   /// x<sub>n+k</sub> = dk]) {s}</i> is <i>(T<sub>1</sub>, &hellip;, T<sub>n</sub>, [T<sub>n+1</sub>
   /// x<sub>n+1</sub>, &hellip;, T<sub>n+k</sub> x<sub>n+k</sub>]) &rarr; dynamic</i>. In any case
   /// where <i>T<sub>i</sub>, 1 &lt;= i &lt;= n</i>, is not specified, it is considered to have been
   /// specified as dynamic.
   ///
   /// The static type of a function literal of the form <i>(T<sub>1</sub> a<sub>1</sub>, &hellip;,
   /// T<sub>n</sub> a<sub>n</sub>, {T<sub>n+1</sub> x<sub>n+1</sub> : d1, &hellip;, T<sub>n+k</sub>
   /// x<sub>n+k</sub> : dk}) {s}</i> is <i>(T<sub>1</sub>, &hellip;, T<sub>n</sub>, {T<sub>n+1</sub>
   /// x<sub>n+1</sub>, &hellip;, T<sub>n+k</sub> x<sub>n+k</sub>}) &rarr; dynamic</i>. In any case
   /// where <i>T<sub>i</sub>, 1 &lt;= i &lt;= n</i>, is not specified, it is considered to have been
   /// specified as dynamic.</blockquote>
   void visitFunctionExpression(FunctionExpression node) {}

   void visitFunctionReference(covariant FunctionReferenceImpl node) {
     // TODO(paulberry): implement
     node.staticType = _dynamicType;
   }

   /// <blockquote>
   /// An integer literal has static type \code{int}, unless the surrounding
   /// static context type is a type which \code{int} is not assignable to, and
   /// \code{double} is. In that case the static type of the integer literal is
   /// \code{double}.
   /// <blockquote>
   ///
   /// and
   ///
   /// <blockquote>
   /// If $e$ is an expression of the form \code{-$l$} where $l$ is an integer
   /// literal (\ref{numbers}) with numeric integer value $i$, then the static
   /// type of $e$ is the same as the static type of an integer literal with the
   /// same contexttype
   /// </blockquote>
   void visitIntegerLiteral(IntegerLiteralImpl node,
       {required DartType? contextType}) {
     if (contextType == null ||
         _typeSystem.isAssignableTo(_typeProvider.intType, contextType) ||
         !_typeSystem.isAssignableTo(_typeProvider.doubleType, contextType)) {
       _inferenceHelper.recordStaticType(node, _typeProvider.intType,
           contextType: contextType);
     } else {
       _inferenceHelper.recordStaticType(node, _typeProvider.doubleType,
           contextType: contextType);
     }
   }

   /// The Dart Language Specification, 12.31: <blockquote>It is a static warning if <i>T</i> does not
   /// denote a type available in the current lexical scope.
   ///
   /// The static type of an is-expression is `bool`.</blockquote>
   void visitIsExpression(covariant IsExpressionImpl node,
       {required DartType? contextType}) {
     _inferenceHelper.recordStaticType(node, _typeProvider.boolType,
         contextType: contextType);
   }

   void visitMethodInvocation(MethodInvocation node) {
     throw StateError('Should not be invoked');
   }

   void visitNamedExpression(covariant NamedExpressionImpl node,
       {required DartType? contextType}) {
     Expression expression = node.expression;
     _inferenceHelper.recordStaticType(node, expression.typeOrThrow,
         contextType: contextType);
   }

   /// The Dart Language Specification, 12.2: <blockquote>The static type of `null` is bottom.
   /// </blockquote>
   void visitNullLiteral(covariant NullLiteralImpl node,
       {required DartType? contextType}) {
     _inferenceHelper.recordStaticType(node, _typeProvider.nullType,
         contextType: contextType);
   }

   void visitParenthesizedExpression(covariant ParenthesizedExpressionImpl node,
       {required DartType? contextType}) {
     Expression expression = node.expression;
     _inferenceHelper.recordStaticType(node, expression.typeOrThrow,
         contextType: contextType);
   }

   /// The Dart Language Specification, 12.9: <blockquote>The static type of a rethrow expression is
   /// bottom.</blockquote>
   void visitRethrowExpression(covariant RethrowExpressionImpl node,
       {required DartType? contextType}) {
     _inferenceHelper.recordStaticType(node, _typeProvider.bottomType,
         contextType: contextType);
   }

   /// The Dart Language Specification, 12.5: <blockquote>The static type of a string literal is
   /// `String`.</blockquote>
   void visitSimpleStringLiteral(covariant SimpleStringLiteralImpl node,
       {required DartType? contextType}) {
     _inferenceHelper.recordStaticType(node, _typeProvider.stringType,
         contextType: contextType);
   }

   /// The Dart Language Specification, 12.5: <blockquote>The static type of a string literal is
   /// `String`.</blockquote>
   void visitStringInterpolation(covariant StringInterpolationImpl node,
       {required DartType? contextType}) {
     _inferenceHelper.recordStaticType(node, _typeProvider.stringType,
         contextType: contextType);
   }

   void visitSuperExpression(covariant SuperExpressionImpl node,
       {required DartType? contextType}) {
     var thisType = _resolver.thisType;
     _resolver.flowAnalysis.flow?.thisOrSuper(node, thisType ?? _dynamicType);
     if (thisType == null ||
         node.thisOrAncestorOfType<ExtensionDeclaration>() != null) {
       // TODO(brianwilkerson) Report this error if it hasn't already been
       // reported.
       _inferenceHelper.recordStaticType(node, _dynamicType,
           contextType: contextType);
     } else {
       _inferenceHelper.recordStaticType(node, thisType,
           contextType: contextType);
     }
   }

   void visitSymbolLiteral(covariant SymbolLiteralImpl node,
       {required DartType? contextType}) {
     _inferenceHelper.recordStaticType(node, _typeProvider.symbolType,
         contextType: contextType);
   }

   /// The Dart Language Specification, 12.10: <blockquote>The static type of `this` is the
   /// interface of the immediately enclosing class.</blockquote>
   void visitThisExpression(covariant ThisExpressionImpl node,
       {required DartType? contextType}) {
     var thisType = _resolver.thisType;
     _resolver.flowAnalysis.flow?.thisOrSuper(node, thisType ?? _dynamicType);
     if (thisType == null) {
       // TODO(brianwilkerson) Report this error if it hasn't already been
       // reported.
       _inferenceHelper.recordStaticType(node, _dynamicType,
           contextType: contextType);
     } else {
       _inferenceHelper.recordStaticType(node, thisType,
           contextType: contextType);
     }
   }

   /// The Dart Language Specification, 12.8: <blockquote>The static type of a throw expression is
   /// bottom.</blockquote>
   void visitThrowExpression(covariant ThrowExpressionImpl node,
       {required DartType? contextType}) {
     _inferenceHelper.recordStaticType(node, _typeProvider.bottomType,
         contextType: contextType);
   }

   /// Set the static type of [node] to be the least upper bound of the static
   /// types of subexpressions [expr1] and [expr2].
   void _analyzeLeastUpperBound(
       ExpressionImpl node, Expression expr1, Expression expr2,
       {required DartType? contextType}) {
     var staticType1 = expr1.typeOrThrow;
     var staticType2 = expr2.typeOrThrow;

     _analyzeLeastUpperBoundTypes(node, staticType1, staticType2,
         contextType: contextType);
   }

   /// Set the static type of [node] to be the least upper bound of the static
   /// types [staticType1] and [staticType2].
   void _analyzeLeastUpperBoundTypes(
       ExpressionImpl node, DartType staticType1, DartType staticType2,
       {required DartType? contextType}) {
     DartType staticType =
         _typeSystem.getLeastUpperBound(staticType1, staticType2);

     staticType = _resolver.toLegacyTypeIfOptOut(staticType);

     _inferenceHelper.recordStaticType(node, staticType,
         contextType: contextType);
   }

   /// Return the type represented by the given type [annotation].
   DartType _getType(TypeAnnotation annotation) {
     var type = annotation.type;
     if (type == null) {
       //TODO(brianwilkerson) Determine the conditions for which the type is
       // null.
       return _dynamicType;
     }
     return type;
   }
 }
	// Copyright (c) 2014, 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/ast/ast.dart';
	import 'package:analyzer/dart/element/type.dart';
	import 'package:analyzer/src/dart/ast/ast.dart';
	import 'package:analyzer/src/dart/ast/extensions.dart';
	import 'package:analyzer/src/dart/element/type_provider.dart';
	import 'package:analyzer/src/dart/element/type_system.dart';
	import 'package:analyzer/src/dart/resolver/invocation_inference_helper.dart';
	import 'package:analyzer/src/generated/resolver.dart';

	/// Instances of the class `StaticTypeAnalyzer` perform two type-related tasks. First, they
	/// compute the static type of every expression. Second, they look for any static type errors or
	/// warnings that might need to be generated. The requirements for the type analyzer are:
	/// <ol>
	/// * Every element that refers to types should be fully populated.
	/// * Every node representing an expression should be resolved to the Type of the expression.
	/// </ol>
	class StaticTypeAnalyzer {
	/// The resolver driving the resolution and type analysis.
	final ResolverVisitor _resolver;

	final InvocationInferenceHelper _inferenceHelper;

	/// The object providing access to the types defined by the language.
	late TypeProviderImpl _typeProvider;

	/// The type system in use for static type analysis.
	late TypeSystemImpl _typeSystem;

	/// The type representing the type 'dynamic'.
	late DartType _dynamicType;

	/// Initialize a newly created static type analyzer to analyze types for the
	/// [_resolver] based on the
	///
	/// @param resolver the resolver driving this participant
	StaticTypeAnalyzer(this._resolver)
	: _inferenceHelper = _resolver.inferenceHelper {
	_typeProvider = _resolver.typeProvider;
	_typeSystem = _resolver.typeSystem;
	_dynamicType = _typeProvider.dynamicType;
	}

	/// The Dart Language Specification, 12.5: <blockquote>The static type of a string literal is
	/// `String`.</blockquote>
	void visitAdjacentStrings(covariant AdjacentStringsImpl node,
	{required DartType? contextType}) {
	_inferenceHelper.recordStaticType(node, _typeProvider.stringType,
	contextType: contextType);
	}

	/// The Dart Language Specification, 12.32: <blockquote>... the cast expression <i>e as T</i> ...
	///
	/// It is a static warning if <i>T</i> does not denote a type available in the current lexical
	/// scope.
	///
	/// The static type of a cast expression <i>e as T</i> is <i>T</i>.</blockquote>
	void visitAsExpression(covariant AsExpressionImpl node,
	{required DartType? contextType}) {
	_inferenceHelper.recordStaticType(node, _getType(node.type),
	contextType: contextType);
	}

	/// The Dart Language Specification, 16.29 (Await Expressions):
	///
	/// The static type of [the expression "await e"] is flatten(T) where T is
	/// the static type of e.
	void visitAwaitExpression(covariant AwaitExpressionImpl node,
	{required DartType? contextType}) {
	var resultType = node.expression.typeOrThrow;
	resultType = _typeSystem.flatten(resultType);
	_inferenceHelper.recordStaticType(node, resultType,
	contextType: contextType);
	}

	/// The Dart Language Specification, 12.4: <blockquote>The static type of a boolean literal is
	/// bool.</blockquote>
	void visitBooleanLiteral(covariant BooleanLiteralImpl node,
	{required DartType? contextType}) {
	_inferenceHelper.recordStaticType(node, _typeProvider.boolType,
	contextType: contextType);
	}

	/// The Dart Language Specification, 12.15.2: <blockquote>A cascaded method invocation expression
	/// of the form <i>e..suffix</i> is equivalent to the expression <i>(t) {t.suffix; return
	/// t;}(e)</i>.</blockquote>
	void visitCascadeExpression(covariant CascadeExpressionImpl node,
	{required DartType? contextType}) {
	_inferenceHelper.recordStaticType(node, node.target.typeOrThrow,
	contextType: contextType);
	}

	/// The Dart Language Specification, 12.19: <blockquote> ... a conditional expression <i>c</i> of
	/// the form <i>e<sub>1</sub> ? e<sub>2</sub> : e<sub>3</sub></i> ...
	///
	/// It is a static type warning if the type of e<sub>1</sub> may not be assigned to `bool`.
	///
	/// The static type of <i>c</i> is the least upper bound of the static type of <i>e<sub>2</sub></i>
	/// and the static type of <i>e<sub>3</sub></i>.</blockquote>
	void visitConditionalExpression(covariant ConditionalExpressionImpl node,
	{required DartType? contextType}) {
	_analyzeLeastUpperBound(node, node.thenExpression, node.elseExpression,
	contextType: contextType);
	}

	/// The Dart Language Specification, 12.3: <blockquote>The static type of a literal double is
	/// double.</blockquote>
	void visitDoubleLiteral(covariant DoubleLiteralImpl node,
	{required DartType? contextType}) {
	_inferenceHelper.recordStaticType(node, _typeProvider.doubleType,
	contextType: contextType);
	}

	void visitExtensionOverride(ExtensionOverride node) {
	assert(false,
	'Resolver should call extensionResolver.resolveOverride directly');
	}

	/// The Dart Language Specification, 12.9: <blockquote>The static type of a function literal of the
	/// form <i>(T<sub>1</sub> a<sub>1</sub>, …, T<sub>n</sub> a<sub>n</sub>, [T<sub>n+1</sub>
	/// x<sub>n+1</sub> = d1, …, T<sub>n+k</sub> x<sub>n+k</sub> = dk]) => e</i> is
	/// <i>(T<sub>1</sub>, …, Tn, [T<sub>n+1</sub> x<sub>n+1</sub>, …, T<sub>n+k</sub>
	/// x<sub>n+k</sub>]) → T<sub>0</sub></i>, where <i>T<sub>0</sub></i> is the static type of
	/// <i>e</i>. In any case where <i>T<sub>i</sub>, 1 <= i <= n</i>, is not specified, it is
	/// considered to have been specified as dynamic.
	///
	/// The static type of a function literal of the form <i>(T<sub>1</sub> a<sub>1</sub>, …,
	/// T<sub>n</sub> a<sub>n</sub>, {T<sub>n+1</sub> x<sub>n+1</sub> : d1, …, T<sub>n+k</sub>
	/// x<sub>n+k</sub> : dk}) => e</i> is <i>(T<sub>1</sub>, …, T<sub>n</sub>, {T<sub>n+1</sub>
	/// x<sub>n+1</sub>, …, T<sub>n+k</sub> x<sub>n+k</sub>}) → T<sub>0</sub></i>, where
	/// <i>T<sub>0</sub></i> is the static type of <i>e</i>. In any case where <i>T<sub>i</sub>, 1
	/// <= i <= n</i>, is not specified, it is considered to have been specified as dynamic.
	///
	/// The static type of a function literal of the form <i>(T<sub>1</sub> a<sub>1</sub>, …,
	/// T<sub>n</sub> a<sub>n</sub>, [T<sub>n+1</sub> x<sub>n+1</sub> = d1, …, T<sub>n+k</sub>
	/// x<sub>n+k</sub> = dk]) {s}</i> is <i>(T<sub>1</sub>, …, T<sub>n</sub>, [T<sub>n+1</sub>
	/// x<sub>n+1</sub>, …, T<sub>n+k</sub> x<sub>n+k</sub>]) → dynamic</i>. In any case
	/// where <i>T<sub>i</sub>, 1 <= i <= n</i>, is not specified, it is considered to have been
	/// specified as dynamic.
	///
	/// The static type of a function literal of the form <i>(T<sub>1</sub> a<sub>1</sub>, …,
	/// T<sub>n</sub> a<sub>n</sub>, {T<sub>n+1</sub> x<sub>n+1</sub> : d1, …, T<sub>n+k</sub>
	/// x<sub>n+k</sub> : dk}) {s}</i> is <i>(T<sub>1</sub>, …, T<sub>n</sub>, {T<sub>n+1</sub>
	/// x<sub>n+1</sub>, …, T<sub>n+k</sub> x<sub>n+k</sub>}) → dynamic</i>. In any case
	/// where <i>T<sub>i</sub>, 1 <= i <= n</i>, is not specified, it is considered to have been
	/// specified as dynamic.</blockquote>
	void visitFunctionExpression(FunctionExpression node) {}

	void visitFunctionReference(covariant FunctionReferenceImpl node) {
	// TODO(paulberry): implement
	node.staticType = _dynamicType;
	}

	/// <blockquote>
	/// An integer literal has static type \code{int}, unless the surrounding
	/// static context type is a type which \code{int} is not assignable to, and
	/// \code{double} is. In that case the static type of the integer literal is
	/// \code{double}.
	/// <blockquote>
	///
	/// and
	///
	/// <blockquote>
	/// If $e$ is an expression of the form \code{-$l$} where $l$ is an integer
	/// literal (\ref{numbers}) with numeric integer value $i$, then the static
	/// type of $e$ is the same as the static type of an integer literal with the
	/// same contexttype
	/// </blockquote>
	void visitIntegerLiteral(IntegerLiteralImpl node,
	{required DartType? contextType}) {
	if (contextType == null \|\|
	_typeSystem.isAssignableTo(_typeProvider.intType, contextType) \|\|
	!_typeSystem.isAssignableTo(_typeProvider.doubleType, contextType)) {
	_inferenceHelper.recordStaticType(node, _typeProvider.intType,
	contextType: contextType);
	} else {
	_inferenceHelper.recordStaticType(node, _typeProvider.doubleType,
	contextType: contextType);
	}
	}

	/// The Dart Language Specification, 12.31: <blockquote>It is a static warning if <i>T</i> does not
	/// denote a type available in the current lexical scope.
	///
	/// The static type of an is-expression is `bool`.</blockquote>
	void visitIsExpression(covariant IsExpressionImpl node,
	{required DartType? contextType}) {
	_inferenceHelper.recordStaticType(node, _typeProvider.boolType,
	contextType: contextType);
	}

	void visitMethodInvocation(MethodInvocation node) {
	throw StateError('Should not be invoked');
	}

	void visitNamedExpression(covariant NamedExpressionImpl node,
	{required DartType? contextType}) {
	Expression expression = node.expression;
	_inferenceHelper.recordStaticType(node, expression.typeOrThrow,
	contextType: contextType);
	}

	/// The Dart Language Specification, 12.2: <blockquote>The static type of `null` is bottom.
	/// </blockquote>
	void visitNullLiteral(covariant NullLiteralImpl node,
	{required DartType? contextType}) {
	_inferenceHelper.recordStaticType(node, _typeProvider.nullType,
	contextType: contextType);
	}

	void visitParenthesizedExpression(covariant ParenthesizedExpressionImpl node,
	{required DartType? contextType}) {
	Expression expression = node.expression;
	_inferenceHelper.recordStaticType(node, expression.typeOrThrow,
	contextType: contextType);
	}

	/// The Dart Language Specification, 12.9: <blockquote>The static type of a rethrow expression is
	/// bottom.</blockquote>
	void visitRethrowExpression(covariant RethrowExpressionImpl node,
	{required DartType? contextType}) {
	_inferenceHelper.recordStaticType(node, _typeProvider.bottomType,
	contextType: contextType);
	}

	/// The Dart Language Specification, 12.5: <blockquote>The static type of a string literal is
	/// `String`.</blockquote>
	void visitSimpleStringLiteral(covariant SimpleStringLiteralImpl node,
	{required DartType? contextType}) {
	_inferenceHelper.recordStaticType(node, _typeProvider.stringType,
	contextType: contextType);
	}

	/// The Dart Language Specification, 12.5: <blockquote>The static type of a string literal is
	/// `String`.</blockquote>
	void visitStringInterpolation(covariant StringInterpolationImpl node,
	{required DartType? contextType}) {
	_inferenceHelper.recordStaticType(node, _typeProvider.stringType,
	contextType: contextType);
	}

	void visitSuperExpression(covariant SuperExpressionImpl node,
	{required DartType? contextType}) {
	var thisType = _resolver.thisType;
	_resolver.flowAnalysis.flow?.thisOrSuper(node, thisType ?? _dynamicType);
	if (thisType == null \|\|
	node.thisOrAncestorOfType<ExtensionDeclaration>() != null) {
	// TODO(brianwilkerson) Report this error if it hasn't already been
	// reported.
	_inferenceHelper.recordStaticType(node, _dynamicType,
	contextType: contextType);
	} else {
	_inferenceHelper.recordStaticType(node, thisType,
	contextType: contextType);
	}
	}

	void visitSymbolLiteral(covariant SymbolLiteralImpl node,
	{required DartType? contextType}) {
	_inferenceHelper.recordStaticType(node, _typeProvider.symbolType,
	contextType: contextType);
	}

	/// The Dart Language Specification, 12.10: <blockquote>The static type of `this` is the
	/// interface of the immediately enclosing class.</blockquote>
	void visitThisExpression(covariant ThisExpressionImpl node,
	{required DartType? contextType}) {
	var thisType = _resolver.thisType;
	_resolver.flowAnalysis.flow?.thisOrSuper(node, thisType ?? _dynamicType);
	if (thisType == null) {
	// TODO(brianwilkerson) Report this error if it hasn't already been
	// reported.
	_inferenceHelper.recordStaticType(node, _dynamicType,
	contextType: contextType);
	} else {
	_inferenceHelper.recordStaticType(node, thisType,
	contextType: contextType);
	}
	}

	/// The Dart Language Specification, 12.8: <blockquote>The static type of a throw expression is
	/// bottom.</blockquote>
	void visitThrowExpression(covariant ThrowExpressionImpl node,
	{required DartType? contextType}) {
	_inferenceHelper.recordStaticType(node, _typeProvider.bottomType,
	contextType: contextType);
	}

	/// Set the static type of [node] to be the least upper bound of the static
	/// types of subexpressions [expr1] and [expr2].
	void _analyzeLeastUpperBound(
	ExpressionImpl node, Expression expr1, Expression expr2,
	{required DartType? contextType}) {
	var staticType1 = expr1.typeOrThrow;
	var staticType2 = expr2.typeOrThrow;

	_analyzeLeastUpperBoundTypes(node, staticType1, staticType2,
	contextType: contextType);
	}

	/// Set the static type of [node] to be the least upper bound of the static
	/// types [staticType1] and [staticType2].
	void _analyzeLeastUpperBoundTypes(
	ExpressionImpl node, DartType staticType1, DartType staticType2,
	{required DartType? contextType}) {
	DartType staticType =
	_typeSystem.getLeastUpperBound(staticType1, staticType2);

	staticType = _resolver.toLegacyTypeIfOptOut(staticType);

	_inferenceHelper.recordStaticType(node, staticType,
	contextType: contextType);
	}

	/// Return the type represented by the given type [annotation].
	DartType _getType(TypeAnnotation annotation) {
	var type = annotation.type;
	if (type == null) {
	//TODO(brianwilkerson) Determine the conditions for which the type is
	// null.
	return _dynamicType;
	}
	return type;
	}
	}