Issue 14685. Don't analyzer parts.

pkg/analyzer/lib/src/analyzer_impl.dart

 // Copyright (c) 2013, 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 analyzer_impl;
 
 import 'dart:io';
 
 import 'generated/java_io.dart';
 import 'generated/engine.dart';
 import 'generated/error.dart';
 import 'generated/source_io.dart';
 import 'generated/sdk.dart';
 import 'generated/sdk_io.dart';
+import 'generated/ast.dart';
 import 'generated/element.dart';
 import '../options.dart';
 
 
 DartSdk sdk;
 
 /// Analyzes single library [File].
 class AnalyzerImpl {
   final CommandLineOptions options;
 
@@ skipping 18 matching lines @@
    */
   void analyze(String sourcePath) {
     sources.clear();
     errorInfos.clear();
     if (sourcePath == null) {
       throw new ArgumentError("sourcePath cannot be null");
     }
     var sourceFile = new JavaFile(sourcePath);
     var uriKind = getUriKind(sourceFile);
     var librarySource = new FileBasedSource.con2(contentCache, sourceFile, uriKind);
+    // prepare context
+    prepareAnalysisContext(sourceFile);
+    // don't try to analyzer parts
+    var unit = context.parseCompilationUnit(librarySource);
+    var hasLibraryDirective = false;
+    var hasPartOfDirective = false;
+    for (var directive in unit.directives) {
+      if (directive is LibraryDirective) hasLibraryDirective = true;
+      if (directive is PartOfDirective) hasPartOfDirective = true;
+    }
+    if (hasPartOfDirective && !hasLibraryDirective) {
+      print("Only libraries can be analyzed.");
+      print("$sourceFile is a part and can not be analyzed.");
+      return;
+    }
     // resolve library
-    prepareAnalysisContext(sourceFile);
     var libraryElement = context.computeLibraryElement(librarySource);
     // prepare source and errors
     prepareSources(libraryElement);
     prepareErrors();
   }
 
   /// Returns the maximal [ErrorSeverity] of the recorded errors.
   ErrorSeverity get maxErrorSeverity {
     var status = ErrorSeverity.NONE;
     for (AnalysisErrorInfo errorInfo in errorInfos) {
@@ skipping 114 matching lines @@
       DirectoryBasedDartSdk directoryBasedSdk = sdk;
       String sdkLibPath = directoryBasedSdk.libraryDirectory.getPath() + JavaFile.separator;
       if (file.getPath().startsWith(sdkLibPath)) {
         return UriKind.DART_URI;
       }
     }
     // some generic file
     return UriKind.FILE_URI;
   }
 }