Update LineInfo during incremental resolution.

pkg/analyzer/test/generated/incremental_resolver_test.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.
 
 library engine.incremental_resolver_test;
 
 import 'package:analyzer/src/context/cache.dart' as task;
 import 'package:analyzer/src/generated/ast.dart';
 import 'package:analyzer/src/generated/element.dart';
 import 'package:analyzer/src/generated/engine.dart';
@@ skipping 3854 matching lines @@
 }
 f2() {
   print(22);
 }
 f3() {
   print(333)
 }
 ''');
   }
 
+  void _assertEqualLineInfo(LineInfo incrLineInfo, LineInfo fullLineInfo) {
+    for (int offset = 0; offset < 1000; offset++) {
+      LineInfo_Location incrLocation = incrLineInfo.getLocation(offset);
+      LineInfo_Location fullLocation = fullLineInfo.getLocation(offset);
+      if (incrLocation.lineNumber != fullLocation.lineNumber ||
+          incrLocation.columnNumber != fullLocation.columnNumber) {
+        fail('At offset $offset ' +
+            '(${incrLocation.lineNumber}, ${incrLocation.columnNumber})' +
+            ' != ' +
+            '(${fullLocation.lineNumber}, ${fullLocation.columnNumber})');
+      }
+    }
+  }
+
   /**
    * Reset the analysis context to have the 'incremental' option set to the
    * given value.
    */
   void _resetWithIncremental(bool enable) {
     AnalysisOptionsImpl analysisOptions = new AnalysisOptionsImpl();
     analysisOptions.incremental = enable;
     analysisOptions.incrementalApi = enable;
 //    log.logger = log.PRINT_LOGGER;
     log.logger = log.NULL_LOGGER;
@@ skipping 18 matching lines @@
   void _updateAndValidate(String newCode,
       {bool expectedSuccess: true, bool compareWithFull: true}) {
     // Run any pending tasks tasks.
     _runTasks();
     // Update the source - currently this may cause incremental resolution.
     // Then request the updated resolved unit.
     _resetWithIncremental(true);
     analysisContext2.setContents(source, newCode);
     CompilationUnit newUnit = resolveCompilationUnit(source, oldLibrary);
     List<AnalysisError> newErrors = analysisContext.computeErrors(source);
+    LineInfo newLineInfo = analysisContext.getLineInfo(source);
     // check for expected failure
     if (!expectedSuccess) {
       expect(newUnit.element, isNot(same(oldUnitElement)));
       return;
     }
     // The existing CompilationUnitElement should be updated.
     expect(newUnit.element, same(oldUnitElement));
     // The only expected pending task should return the same resolved
     // "newUnit", so all clients will get it using the usual way.
     AnalysisResult analysisResult = analysisContext.performAnalysisTask();
     ChangeNotice notice = analysisResult.changeNotices[0];
     expect(notice.resolvedDartUnit, same(newUnit));
     // Resolve "newCode" from scratch.
     if (compareWithFull) {
       _resetWithIncremental(false);
       source = addSource(newCode + ' ');
       source = addSource(newCode);
       _runTasks();
       LibraryElement library = resolve2(source);
       CompilationUnit fullNewUnit = resolveCompilationUnit(source, library);
       // Validate tokens.
       _assertEqualTokens(newUnit, fullNewUnit);
+      // Validate LineInfo
+      _assertEqualLineInfo(newLineInfo, analysisContext.getLineInfo(source));
       // Validate that "incremental" and "full" units have the same resolution.
       try {
         assertSameResolution(newUnit, fullNewUnit, validateTypes: true);
       } on IncrementalResolutionMismatch catch (mismatch) {
         fail(mismatch.message);
       }
       List<AnalysisError> newFullErrors =
           analysisContext.getErrors(source).errors;
       _assertEqualErrors(newErrors, newFullErrors);
-      // TODO(scheglov) check line info
     }
   }
 
   static void _assertEqualToken(Token incrToken, Token fullToken) {
 //    print('[${incrToken.offset}] |$incrToken| vs. [${fullToken.offset}] |$fullToken|');
     expect(incrToken.type, fullToken.type);
     expect(incrToken.offset, fullToken.offset);
     expect(incrToken.length, fullToken.length);
     expect(incrToken.lexeme, fullToken.lexeme);
   }
@@ skipping 221 matching lines @@
     return ResolutionContextBuilder.contextFor(node, listener).scope;
   }
 }
 
 class _Edit {
   final int offset;
   final int length;
   final String replacement;
   _Edit(this.offset, this.length, this.replacement);
 }