Embedded options discovery (#24943).

pkg/analysis_server/lib/src/context_manager.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 context.directory.manager;
 
 import 'dart:async';
 import 'dart:collection';
 import 'dart:convert';
 import 'dart:core' hide Resource;
@@ skipping 11 matching lines @@
 import 'package:analyzer/source/pub_package_map_provider.dart';
 import 'package:analyzer/source/sdk_ext.dart';
 import 'package:analyzer/src/context/context.dart' as context;
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/java_engine.dart';
 import 'package:analyzer/src/generated/java_io.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/generated/source_io.dart';
 import 'package:analyzer/src/task/options.dart';
 import 'package:analyzer/src/util/absolute_path.dart';
+import 'package:analyzer/src/util/yaml.dart';
 import 'package:package_config/packages.dart';
 import 'package:package_config/packages_file.dart' as pkgfile show parse;
 import 'package:package_config/src/packages_impl.dart' show MapPackages;
 import 'package:path/path.dart' as pathos;
 import 'package:watcher/watcher.dart';
 import 'package:yaml/yaml.dart';
 
 /**
  * Information tracked by the [ContextManager] for each context.
  */
@@ skipping 451 matching lines @@
         .forEach((OptionsProcessor p) {
       try {
         p.optionsProcessed(info.context, options);
       } catch (e, stacktrace) {
         AnalysisEngine.instance.logger.logError(
             'Error processing .analysis_options',
             new CaughtException(e, stacktrace));
       }
     });
 
-    // In case options files are removed, revert to default options.
+    // In case options files are removed, revert to defaults.
     if (optionsRemoved) {
+      // Start with defaults.
       info.context.analysisOptions = new AnalysisOptionsImpl();
+
+      // Apply inherited options.
+      YamlMap embeddedOptions = _getEmbeddedOptions(info.context);
+      if (embeddedOptions != null) {
+        configureContextOptions(info.context, embeddedOptions);
+      }
       return;
     }
 
+    // Check for embedded options.
+    YamlMap embeddedOptions = _getEmbeddedOptions(info.context);
+    if (embeddedOptions != null) {
+      options = new Merger().merge(embeddedOptions, options);
+    }
+
     // Analysis options are processed 'in-line'.
     var analyzer = options[AnalyzerOptions.analyzer];
-    if (analyzer is! YamlMap) {
+    if (analyzer is! Map) {
       // No options for analyzer.
       return;
     }
 
     configureContextOptions(info.context, options);
 
     // Set ignore patterns.
     YamlList exclude = analyzer[AnalyzerOptions.exclude];
     if (exclude != null) {
       setIgnorePatternsForContext(info, exclude);
@@ skipping 479 matching lines @@
     // Start by looking for .packages.
     packageSpec = folder.getChild(PACKAGE_SPEC_NAME);
 
     // Fall back to looking for a pubspec.
     if (packageSpec == null || !packageSpec.exists) {
       packageSpec = folder.getChild(PUBSPEC_NAME);
     }
     return packageSpec;
   }
 
+  /// Get analysis options associated with an `_embedder.yaml`. If there is
+  /// more than one `_embedder.yaml` associated with the given context, `null`
+  /// is returned.
+  YamlMap _getEmbeddedOptions(AnalysisContext context) {
+    if (context is InternalAnalysisContext) {
+      EmbedderYamlLocator locator = context.embedderYamlLocator;
+      Iterable<YamlMap> maps = locator.embedderYamls.values;
+      if (maps.length == 1) {
+        return maps.first;
+      }
+    }
+    return null;
+  }
+
   /**
    * Return the [ContextInfo] for the "innermost" context whose associated
    * folder is or contains the given path.  ("innermost" refers to the nesting
    * of contexts, so if there is a context for path /foo and a context for
    * path /foo/bar, then the innermost context containing /foo/bar/baz.dart is
    * the context for /foo/bar.)
    *
    * If no context contains the given path, `null` is returned.
    */
   ContextInfo _getInnermostContextInfoFor(String path) {
@@ skipping 426 matching lines @@
 }
 
 /**
  * Concrete [FolderDisposition] object indicating that the context for a given
  * folder should resolve packages using a ".packages" file.
  */
 class PackagesFileDisposition extends FolderDisposition {
   @override
   final Packages packages;
 
+  PackagesFileDisposition(this.packages) {}
+
+  @override
+  String get packageRoot => null;
+
   Map<String, List<Folder>> buildPackageMap(ResourceProvider resourceProvider) {
     Map<String, List<Folder>> packageMap = <String, List<Folder>>{};
     if (packages == null) {
       return packageMap;
     }
     packages.asMap().forEach((String name, Uri uri) {
       if (uri.scheme == 'file' || uri.scheme == '' /* unspecified */) {
         var path = resourceProvider.pathContext.fromUri(uri);
         packageMap[name] = <Folder>[resourceProvider.getFolder(path)];
       }
     });
     return packageMap;
   }
 
-  PackagesFileDisposition(this.packages) {}
-
-  @override
-  String get packageRoot => null;
-
   @override
   Iterable<UriResolver> createPackageUriResolvers(
       ResourceProvider resourceProvider) {
     if (packages != null) {
       // Construct package map for the SdkExtUriResolver.
-      Map<String, List<Folder>> packageMap =
-          buildPackageMap(resourceProvider);
+      Map<String, List<Folder>> packageMap = buildPackageMap(resourceProvider);
       return <UriResolver>[new SdkExtUriResolver(packageMap)];
     } else {
       return const <UriResolver>[];
     }
   }
 }