Add hook to command-line analyzer similar to server

R=pquitslund@google.com

Review URL: https://codereview.chromium.org/1646413003 .

pkg/analyzer_cli/bin/analyzer.dart

@@ -3,14 +3,10 @@
 // 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_cli/src/driver.dart';
+import 'package:analyzer_cli/starter.dart';
 
-
-
-
-/// The entry point for the analyzer.
+/// The entry point for the command-line analyzer.
 void main(List<String> args) {
-  var starter = new Driver();
+  CommandLineStarter starter = new CommandLineStarter();
   starter.start(args);
-  
 }

pkg/analyzer_cli/lib/plugin/analysis/resolver_provider.dart

@@ -0,0 +1,16 @@
+// 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_cli.plugin.analysis.resolver_provider;
+
+import 'package:analyzer/file_system/file_system.dart';
+import 'package:analyzer/src/generated/source.dart';
+
+/**
+ * A function that will return a [UriResolver] that can be used to resolve a
+ * specific kind of URI within the analysis context rooted at the given folder.
+ * This is currently being used to provide a package URI resolver that will be
+ * used by the server (see [ServerStarter.packageResolverProvider]).
+ */
+typedef UriResolver ResolverProvider(Folder folder);

pkg/analyzer_cli/lib/src/driver.dart

@@ -30,9 +30,11 @@ import 'package:analyzer/src/generated/utilities_general.dart'
     show PerformanceTag;
 import 'package:analyzer/src/services/lint.dart';
 import 'package:analyzer/src/task/options.dart';
+import 'package:analyzer_cli/plugin/analysis/resolver_provider.dart';
 import 'package:analyzer_cli/src/analyzer_impl.dart';
 import 'package:analyzer_cli/src/options.dart';
 import 'package:analyzer_cli/src/perf_report.dart';
+import 'package:analyzer_cli/starter.dart';
 import 'package:linter/src/plugin/linter_plugin.dart';
 import 'package:package_config/discovery.dart' as pkgDiscovery;
 import 'package:package_config/packages.dart' show Packages;
@@ -61,7 +63,7 @@ bool containsLintRuleEntry(Map<String, YamlNode> options) {
 
 typedef ErrorSeverity _BatchRunnerHandler(List<String> args);
 
-class Driver {
+class Driver implements CommandLineStarter {
   static final PerformanceTag _analyzeAllTag =
       new PerformanceTag("Driver._analyzeAll");
 
@@ -79,17 +81,20 @@ class Driver {
   /// creation.
   CommandLineOptions _previousOptions;
 
+  @override
+  ResolverProvider packageResolverProvider;
+
   /// This Driver's current analysis context.
   ///
   /// *Visible for testing.*
   AnalysisContext get context => _context;
 
-  /// Set the [plugins] that are defined outside the `analyzer_cli` package.
+  @override
   void set userDefinedPlugins(List<Plugin> plugins) {
     _userDefinedPlugins = plugins == null ? <Plugin>[] : plugins;
   }
 
-  /// Use the given command-line [args] to start this analysis driver.
+  @override
   void start(List<String> args) {
     int startTime = new DateTime.now().millisecondsSinceEpoch;
 
@@ -309,6 +314,21 @@ class Driver {
     Map<String, List<fileSystem.Folder>> packageMap;
     UriResolver packageUriResolver;
 
+    // Create a custom package resolver if one has been specified.
+    if (packageResolverProvider != null) {
+      fileSystem.Folder folder =
+          PhysicalResourceProvider.INSTANCE.getResource('.');
+      UriResolver resolver = packageResolverProvider(folder);
+      if (resolver != null) {
+        // TODO(brianwilkerson) This doesn't support either embedder files or sdk extensions.
+        List<UriResolver> resolvers = <UriResolver>[
+          new DartUriResolver(sdk),
+          resolver,
+          new FileUriResolver()
+        ];
+        return new SourceFactory(resolvers);
+      }
+    }
     // Process options, caching package resolution details.
     if (options.packageConfigPath != null) {
       String packageConfigPath = options.packageConfigPath;

pkg/analyzer_cli/lib/starter.dart

@@ -0,0 +1,40 @@
+// 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_cli.starter;
+
+import 'package:analyzer_cli/plugin/analysis/resolver_provider.dart';
+import 'package:analyzer_cli/src/driver.dart';
+import 'package:plugin/plugin.dart';
+
+/**
+ * An object that can be used to start a command-line analysis. This class
+ * exists so that clients can configure a command-line analyzer before starting
+ * it.
+ *
+ * Clients may not extend, implement or mix-in this class.
+ */
+abstract class CommandLineStarter {
+  /**
+   * Initialize a newly created starter to start up a command-line analysis.
+   */
+  factory CommandLineStarter() = Driver;
+
+  /**
+   * Set the package resolver provider used to override the way package URI's
+   * are resolved in some contexts. The provider should return `null` if the
+   * default package resolution scheme should be used instead.
+   */
+  void set packageResolverProvider(ResolverProvider provider);
+
+  /**
+   * Set the [plugins] that are defined outside the analyzer_cli package.
+   */
+  void set userDefinedPlugins(List<Plugin> plugins);
+
+  /**
+   * Use the given command-line [arguments] to start this analyzer.
+   */
+  void start(List<String> arguments);
+}