Remove most of the remaining references to AnalysisContext

pkg/analysis_server/lib/src/services/refactoring/extract_method.dart

 // 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 'dart:async';
 
 import 'package:analysis_server/src/protocol_server.dart' hide Element;
 import 'package:analysis_server/src/services/correction/name_suggestion.dart';
 import 'package:analysis_server/src/services/correction/selection_analyzer.dart';
 import 'package:analysis_server/src/services/correction/statement_analyzer.dart';
 import 'package:analysis_server/src/services/correction/status.dart';
 import 'package:analysis_server/src/services/correction/util.dart';
 import 'package:analysis_server/src/services/refactoring/naming_conventions.dart';
 import 'package:analysis_server/src/services/refactoring/refactoring.dart';
 import 'package:analysis_server/src/services/refactoring/refactoring_internal.dart';
 import 'package:analysis_server/src/services/refactoring/rename_class_member.dart';
 import 'package:analysis_server/src/services/refactoring/rename_unit_member.dart';
 import 'package:analysis_server/src/services/search/search_engine.dart';
+import 'package:analyzer/dart/analysis/session.dart';
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/standard_resolution_map.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/src/dart/ast/utilities.dart';
 import 'package:analyzer/src/dart/element/ast_provider.dart';
-import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/java_core.dart';
 import 'package:analyzer/src/generated/resolver.dart' show ExitDetector;
 import 'package:analyzer/src/generated/source.dart';
+import 'package:analyzer/src/generated/type_system.dart';
 import 'package:analyzer_plugin/utilities/range_factory.dart';
 
 const String _TOKEN_SEPARATOR = '\uFFFF';
 
 Element _getLocalElement(SimpleIdentifier node) {
   Element element = node.staticElement;
   if (element is LocalVariableElement ||
       element is ParameterElement ||
       element is FunctionElement && element.visibleRange != null) {
     return element;
@@ skipping 28 matching lines @@
     implements ExtractMethodRefactoring {
   static const ERROR_EXITS =
       'Selected statements contain a return statement, but not all possible '
       'execution flows exit. Semantics may not be preserved.';
 
   final SearchEngine searchEngine;
   final AstProvider astProvider;
   final CompilationUnit unit;
   final int selectionOffset;
   final int selectionLength;
-  AnalysisContext context;
+  AnalysisSession session;
   CompilationUnitElement unitElement;
   LibraryElement libraryElement;
   SourceRange selectionRange;
   CorrectionUtils utils;
   Set<Source> librariesToImport = new Set<Source>();
 
   String returnType = '';
   String variableType;
   String name;
   bool extractAll = true;
@@ skipping 26 matching lines @@
   Expression _selectionExpression;
   FunctionExpression _selectionFunctionExpression;
   List<Statement> _selectionStatements;
   List<_Occurrence> _occurrences = [];
   bool _staticContext = false;
 
   ExtractMethodRefactoringImpl(this.searchEngine, this.astProvider, this.unit,
       this.selectionOffset, this.selectionLength) {
     unitElement = unit.element;
     libraryElement = unitElement.library;
-    context = libraryElement.context;
+    session = astProvider.driver.currentSession;
     selectionRange = new SourceRange(selectionOffset, selectionLength);
     utils = new CorrectionUtils(unit);
   }
 
   @override
   List<RefactoringMethodParameter> get parameters => _parameters;
 
   @override
   void set parameters(List<RefactoringMethodParameter> parameters) {
     _parameters = parameters.toList();
@@ skipping 51 matching lines @@
   Future<RefactoringStatus> checkFinalConditions() async {
     RefactoringStatus result = new RefactoringStatus();
     result.addStatus(validateMethodName(name));
     result.addStatus(_checkParameterNames());
     RefactoringStatus status = await _checkPossibleConflicts();
     result.addStatus(status);
     return result;
   }
 
   @override
-  Future<RefactoringStatus> checkInitialConditions() {
+  Future<RefactoringStatus> checkInitialConditions() async {
     RefactoringStatus result = new RefactoringStatus();
     // selection
     result.addStatus(_checkSelection());
     if (result.hasFatalError) {
-      return new Future.value(result);
+      return result;
     }
     // prepare parts
-    result.addStatus(_initializeParameters());
+    result.addStatus(await _initializeParameters());
     _initializeHasAwait();
-    _initializeReturnType();
+    await _initializeReturnType();
     // occurrences
     _initializeOccurrences();
     _prepareOffsetsLengths();
     // getter
     canCreateGetter = _computeCanCreateGetter();
     createGetter =
         canCreateGetter && _isExpressionForGetter(_selectionExpression);
     // names
     _prepareExcludedNames();
     _prepareNames();
     // closure cannot have parameters
     if (_selectionFunctionExpression != null && !_parameters.isEmpty) {
       String message = format(
           'Cannot extract closure as method, it references {0} external variable(s).',
           _parameters.length);
-      RefactoringStatus result = new RefactoringStatus.fatal(message);
-      return new Future.value(result);
+      return new RefactoringStatus.fatal(message);
     }
-    return new Future.value(result);
+    return result;
   }
 
   @override
   RefactoringStatus checkName() {
     return validateMethodName(name);
   }
 
   @override
   Future<SourceChange> createChange() async {
     SourceChange change = new SourceChange(refactoringName);
@@ skipping 422 matching lines @@
     AstNode enclosingMemberParent = _parentMember.parent;
     // visit nodes which will able to access extracted method
     enclosingMemberParent.accept(new _InitializeOccurrencesVisitor(
         this, selectionPattern, patternToSelectionName));
   }
 
   /**
    * Prepares information about used variables, which should be turned into
    * parameters.
    */
-  RefactoringStatus _initializeParameters() {
+  Future<RefactoringStatus> _initializeParameters() async {
     _parameters.clear();
     _parametersMap.clear();
     _parameterReferencesMap.clear();
     RefactoringStatus result = new RefactoringStatus();
     List<VariableElement> assignedUsedVariables = [];
     unit.accept(new _InitializeParametersVisitor(this, assignedUsedVariables));
     // single expression
     if (_selectionExpression != null) {
       _returnType = _selectionExpression.bestType;
     }
     // verify that none or all execution flows end with a "return"
     if (_selectionStatements != null) {
       bool hasReturn = _selectionStatements.any(_mayEndWithReturnStatement);
       if (hasReturn && !ExitDetector.exits(_selectionStatements.last)) {
         result.addError(ERROR_EXITS);
       }
     }
     // maybe ends with "return" statement
     if (_selectionStatements != null) {
-      _ReturnTypeComputer returnTypeComputer = new _ReturnTypeComputer(context);
+      _ReturnTypeComputer returnTypeComputer =
+          new _ReturnTypeComputer(await session.typeSystem);
       _selectionStatements.forEach((statement) {
         statement.accept(returnTypeComputer);
       });
       _returnType = returnTypeComputer.returnType;
     }
     // maybe single variable to return
     if (assignedUsedVariables.length == 1) {
       // we cannot both return variable and have explicit return statement
       if (_returnType != null) {
         result.addFatalError(
@@ skipping 15 matching lines @@
       }
       result.addFatalError(format(
           'Ambiguous return value: Selected block contains more than one '
           'assignment to local variables. Affected variables are:\n\n{0}',
           sb.toString().trim()));
     }
     // done
     return result;
   }
 
-  void _initializeReturnType() {
-    InterfaceType futureType = context.typeProvider.futureType;
+  Future<Null> _initializeReturnType() async {
+    InterfaceType futureType = (await session.typeProvider).futureType;
     if (_selectionFunctionExpression != null) {
       variableType = '';
       returnType = '';
     } else if (_returnType == null) {
       variableType = null;
       if (_hasAwait) {
         returnType = _getTypeCode(futureType);
       } else {
         returnType = 'void';
       }
@@ skipping 517 matching lines @@
 class _Occurrence {
   final SourceRange range;
   final bool isSelection;
 
   Map<String, String> _parameterOldToOccurrenceName = <String, String>{};
 
   _Occurrence(this.range, this.isSelection);
 }
 
 class _ReturnTypeComputer extends RecursiveAstVisitor {
-  final AnalysisContext context;
+  final TypeSystem typeSystem;
 
   DartType returnType;
 
-  _ReturnTypeComputer(this.context);
+  _ReturnTypeComputer(this.typeSystem);
 
   @override
   visitBlockFunctionBody(BlockFunctionBody node) {}
 
   @override
   visitReturnStatement(ReturnStatement node) {
     // prepare expression
     Expression expression = node.expression;
     if (expression == null) {
       return;
     }
     // prepare type
     DartType type = expression.bestType;
     if (type.isBottom) {
       return;
     }
     // combine types
     if (returnType == null) {
       returnType = type;
     } else {
       if (returnType is InterfaceType && type is InterfaceType) {
         returnType = InterfaceType.getSmartLeastUpperBound(returnType, type);
       } else {
-        returnType = context.typeSystem.getLeastUpperBound(returnType, type);
+        returnType = typeSystem.getLeastUpperBound(returnType, type);
       }
     }
   }
 }
 
 /**
  * Generalized version of some source, in which references to the specific
  * variables are replaced with pattern variables, with back mapping from the
  * pattern to the original variable names.
  */
@@ skipping 10 matching lines @@
       return false;
     }
     for (int i = 0; i < parameterTypes.length; i++) {
       if (other.parameterTypes[i] != parameterTypes[i]) {
         return false;
       }
     }
     return true;
   }
 }