Possible fix for 28038

pkg/analyzer/lib/src/context/builder.dart

 // Copyright (c) 2016, 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.src.context.context_builder;
 
 import 'dart:collection';
 import 'dart:core';
 
 import 'package:analyzer/context/declared_variables.dart';
@@ skipping 234 matching lines @@
     return findPackagesFromFile(rootDirectoryPath);
   }
 
   SourceFactory createSourceFactory(String rootPath, AnalysisOptions options) {
     Workspace workspace = createWorkspace(rootPath);
     DartSdk sdk = findSdk(workspace.packageMap, options);
     return workspace.createSourceFactory(sdk);
   }
 
   Workspace createWorkspace(String rootPath) {
+    if (_hasPackageFileInPath(rootPath)) {
+      // Bazel workspaces that include package files are treated like normal
+      // (non-Bazel) directories.
+      return _BasicWorkspace.find(resourceProvider, rootPath, this);
+    }
     Workspace workspace = BazelWorkspace.find(resourceProvider, rootPath);
     workspace ??= GnWorkspace.find(resourceProvider, rootPath);
     return workspace ?? _BasicWorkspace.find(resourceProvider, rootPath, this);
   }
 
   /**
    * Add any [declaredVariables] to the list of declared variables used by the
    * given [context].
    */
   void declareVariables(InternalAnalysisContext context) {
@@ skipping 281 matching lines @@
     Folder parentDir = folder.parent;
     while (parentDir != null) {
       packagesCfgFile = checkForConfigFile(parentDir);
       if (packagesCfgFile != null) {
         return packagesCfgFile;
       }
       parentDir = parentDir.parent;
     }
     return null;
   }
+
+  /**
+   * Return `true` if either the directory at [rootPath] or a parent of that
+   * directory contains a `.packages` file.
+   */
+  bool _hasPackageFileInPath(String rootPath) {
+    Folder folder = resourceProvider.getFolder(rootPath);
+    while (folder != null) {
+      File file = folder.getChildAssumingFile('.packages');
+      if (file.exists) {
+        return true;
+      }
+      folder = folder.parent;
+    }
+    return false;
+  }
 }
 
 /**
  * Options used by a [ContextBuilder].
  */
 class ContextBuilderOptions {
   /**
    * The results of parsing the command line arguments as defined by
    * [defineAnalysisArguments] or `null` if none.
    */
@@ skipping 163 matching lines @@
 
   final ContextBuilder _builder;
 
   Map<String, List<Folder>> _packageMap;
 
   Packages _packages;
 
   _BasicWorkspace._(this.provider, this.root, this._builder);
 
   @override
+  // Alternately, we could check the pubspec for "sdk: flutter"
+  bool get hasFlutterDependency => packageMap.containsKey('flutter');
+
+  @override
   Map<String, List<Folder>> get packageMap {
     _packageMap ??= _builder.convertPackagesToMap(packages);
     return _packageMap;
   }
 
-  @override
-  // Alternately, we could check the pubspec for "sdk: flutter"
-  bool get hasFlutterDependency => packageMap.containsKey('flutter');
-
   Packages get packages {
     _packages ??= _builder.createPackageMap(root);
     return _packages;
   }
 
   @override
   UriResolver get packageUriResolver =>
       new PackageMapUriResolver(provider, packageMap);
 
   @override
   SourceFactory createSourceFactory(DartSdk sdk) {
     List<UriResolver> resolvers = <UriResolver>[];
     if (sdk != null) {
       resolvers.add(new DartUriResolver(sdk));
     }
     resolvers.add(packageUriResolver);
     resolvers.add(new ResourceUriResolver(provider));
     return new SourceFactory(resolvers, packages, provider);
   }
 
   /**
    * Find the basic workspace that contains the given [path].
    */
   static _BasicWorkspace find(
       ResourceProvider resourceProvider, String path, ContextBuilder builder) {
     return new _BasicWorkspace._(resourceProvider, path, builder);
   }
 }