Embedded options discovery (#24943).

Merges analysis options extracted from `_embedder.yaml` files (potentially) with local overrides.

Background: https://github.com/dart-lang/sdk/issues/24943

For test coverage of merging, see: `analyzer/test/src/util/yaml_test.dart`.

BUG=24943
R=brianwilkerson@google.com, johnmccutchan@google.com

Review URL: https://codereview.chromium.org/1445363002 .

pkg/analysis_server/lib/src/context_manager.dart

@@ -28,6 +28,7 @@ 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;
@@ -515,15 +516,28 @@ class ContextManagerImpl implements ContextManager {
       }
     });
 
-    // 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;
     }
@@ -1023,6 +1037,20 @@ class ContextManagerImpl implements ContextManager {
     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

pkg/analysis_server/test/context_manager_test.dart

@@ -93,6 +93,80 @@ class AbstractContextManagerTest {
     resourceProvider.newFolder(projPath);
   }
 
+  test_embedder_options() async {
+    // Create files.
+    String libPath = newFolder([projPath, LIB_NAME]);
+    String sdkExtPath = newFolder([projPath, 'sdk_ext']);
+    newFile([projPath, 'test', 'test.dart']);
+    newFile([sdkExtPath, 'entry.dart']);
+    // Setup _embedder.yaml.
+    newFile(
+        [libPath, '_embedder.yaml'],
+        r'''
+embedder_libs:
+  "dart:foobar": "../sdk_ext/entry.dart"
+analyzer:
+  strong-mode: true
+  language:
+    enableSuperMixins: true
+''');
+    // Setup .packages file
+    newFile(
+        [projPath, '.packages'],
+        r'''
+test_pack:lib/''');
+
+    // Setup .analysis_options
+    newFile(
+        [projPath, AnalysisEngine.ANALYSIS_OPTIONS_FILE],
+        r'''
+analyzer:
+  exclude:
+    - 'test/**'
+  language:
+    enableGenericMethods: true
+  errors:
+    unused_local_variable: false
+''');
+
+    // Setup context.
+    manager.setRoots(<String>[projPath], <String>[], <String, String>{});
+    await pumpEventQueue();
+
+    // Confirm that one context was created.
+    var contexts =
+        manager.contextsInAnalysisRoot(resourceProvider.newFolder(projPath));
+    expect(contexts, isNotNull);
+    expect(contexts, hasLength(1));
+    var context = contexts[0];
+
+    // Verify options.
+    //   * from `_embedder.yaml`:
+    expect(context.analysisOptions.strongMode, isTrue);
+    expect(context.analysisOptions.enableSuperMixins, isTrue);
+    //   * from `.analysis_options`:
+    expect(context.analysisOptions.enableGenericMethods, isTrue);
+    //     verify tests are excluded
+    expect(callbacks.currentContextFilePaths[projPath].keys,
+        ['/my/proj/sdk_ext/entry.dart']);
+
+    // Verify filter setup.
+    List<ErrorFilter> filters =
+        callbacks.currentContext.getConfigurationData(CONFIGURED_ERROR_FILTERS);
+    expect(filters, hasLength(1));
+    expect(
+        filters.first(new AnalysisError(
+            new TestSource(), 0, 1, HintCode.UNUSED_LOCAL_VARIABLE, [
+          ['x']
+        ])),
+        isTrue);
+
+    // Sanity check embedder libs.
+    var source = context.sourceFactory.forUri('dart:foobar');
+    expect(source, isNotNull);
+    expect(source.fullName, '/my/proj/sdk_ext/entry.dart');
+  }
+
   test_analysis_options_parse_failure() async {
     // Create files.
     String libPath = newFolder([projPath, LIB_NAME]);
@@ -138,6 +212,49 @@ class AbstractContextManagerTest {
     expect(contexts, contains(subProjContextInfo.context));
   }
 
+  test_embedder_packagespec() async {
+    // Create files.
+    String libPath = newFolder([projPath, LIB_NAME]);
+    newFile([libPath, 'main.dart']);
+    newFile([libPath, 'nope.dart']);
+    String sdkExtPath = newFolder([projPath, 'sdk_ext']);
+    newFile([sdkExtPath, 'entry.dart']);
+    String sdkExtSrcPath = newFolder([projPath, 'sdk_ext', 'src']);
+    newFile([sdkExtSrcPath, 'part.dart']);
+    // Setup _embedder.yaml.
+    newFile(
+        [libPath, '_embedder.yaml'],
+        r'''
+embedder_libs:
+  "dart:foobar": "../sdk_ext/entry.dart"
+  "dart:typed_data": "../sdk_ext/src/part"
+  ''');
+    // Setup .packages file
+    newFile(
+        [projPath, '.packages'],
+        r'''
+test_pack:lib/''');
+    // Setup context.
+
+    manager.setRoots(<String>[projPath], <String>[], <String, String>{});
+    await pumpEventQueue();
+    // Confirm that one context was created.
+    var contexts =
+        manager.contextsInAnalysisRoot(resourceProvider.newFolder(projPath));
+    expect(contexts, isNotNull);
+    expect(contexts.length, equals(1));
+    var context = contexts[0];
+    var source = context.sourceFactory.forUri('dart:foobar');
+    expect(source, isNotNull);
+    expect(source.fullName, equals('/my/proj/sdk_ext/entry.dart'));
+    // We can't find dart:core because we didn't list it in our
+    // embedder_libs map.
+    expect(context.sourceFactory.forUri('dart:core'), isNull);
+    // We can find dart:typed_data because we listed it in our
+    // embedder_libs map.
+    expect(context.sourceFactory.forUri('dart:typed_data'), isNotNull);
+  }
+
   test_error_filter_analysis_option() async {
     // Create files.
     newFile(
@@ -568,49 +685,6 @@ analyzer:
     });
   }
 
-  test_embedder_packagespec() async {
-    // Create files.
-    String libPath = newFolder([projPath, LIB_NAME]);
-    newFile([libPath, 'main.dart']);
-    newFile([libPath, 'nope.dart']);
-    String sdkExtPath = newFolder([projPath, 'sdk_ext']);
-    newFile([sdkExtPath, 'entry.dart']);
-    String sdkExtSrcPath = newFolder([projPath, 'sdk_ext', 'src']);
-    newFile([sdkExtSrcPath, 'part.dart']);
-    // Setup _embedder.yaml.
-    newFile(
-        [libPath, '_embedder.yaml'],
-        r'''
-embedder_libs:
-  "dart:foobar": "../sdk_ext/entry.dart"
-  "dart:typed_data": "../sdk_ext/src/part"
-  ''');
-    // Setup .packages file
-    newFile(
-        [projPath, '.packages'],
-        r'''
-test_pack:lib/''');
-    // Setup context.
-
-    manager.setRoots(<String>[projPath], <String>[], <String, String>{});
-    await pumpEventQueue();
-    // Confirm that one context was created.
-    var contexts =
-        manager.contextsInAnalysisRoot(resourceProvider.newFolder(projPath));
-    expect(contexts, isNotNull);
-    expect(contexts.length, equals(1));
-    var context = contexts[0];
-    var source = context.sourceFactory.forUri('dart:foobar');
-    expect(source, isNotNull);
-    expect(source.fullName, equals('/my/proj/sdk_ext/entry.dart'));
-    // We can't find dart:core because we didn't list it in our
-    // embedder_libs map.
-    expect(context.sourceFactory.forUri('dart:core'), isNull);
-    // We can find dart:typed_data because we listed it in our
-    // embedder_libs map.
-    expect(context.sourceFactory.forUri('dart:typed_data'), isNotNull);
-  }
-
   test_sdk_ext_packagespec() async {
     // Create files.
     String libPath = newFolder([projPath, LIB_NAME]);
@@ -1943,19 +2017,6 @@ class TestContextManagerCallbacks extends ContextManagerCallbacks {
    */
   Iterable<String> get currentContextPaths => currentContextTimestamps.keys;
 
-  /// If [disposition] has a package map, attempt to locate `_embedder.yaml`
-  /// files.
-  void _locateEmbedderYamls(InternalAnalysisContext context,
-                            FolderDisposition disposition) {
-    Map<String, List<Folder>> packageMap;
-    if (disposition is PackageMapDisposition) {
-      packageMap = disposition.packageMap;
-    } else if (disposition is PackagesFileDisposition) {
-      packageMap = disposition.buildPackageMap(resourceProvider);
-    }
-    context.embedderYamlLocator.refresh(packageMap);
-  }
-
   @override
   AnalysisContext addContext(Folder folder, FolderDisposition disposition) {
     String path = folder.path;
@@ -2046,6 +2107,19 @@ class TestContextManagerCallbacks extends ContextManagerCallbacks {
       Folder contextFolder, FolderDisposition disposition) {
     currentContextDispositions[contextFolder.path] = disposition;
   }
+
+  /// If [disposition] has a package map, attempt to locate `_embedder.yaml`
+  /// files.
+  void _locateEmbedderYamls(
+      InternalAnalysisContext context, FolderDisposition disposition) {
+    Map<String, List<Folder>> packageMap;
+    if (disposition is PackageMapDisposition) {
+      packageMap = disposition.packageMap;
+    } else if (disposition is PackagesFileDisposition) {
+      packageMap = disposition.buildPackageMap(resourceProvider);
+    }
+    context.embedderYamlLocator.refresh(packageMap);
+  }
 }
 
 /**

pkg/analyzer/lib/src/task/options.dart

@@ -227,28 +227,6 @@ class GenerateOptionsErrorsTask extends SourceBasedAnalysisTask {
       new GenerateOptionsErrorsTask(context, target);
 }
 
-/// Validates `analyzer` strong-mode value configuration options.
-class StrongModeOptionValueValidator extends OptionsValidator {
-  ErrorBuilder trueOrFalseBuilder = new TrueOrFalseValueErrorBuilder();
-
-  @override
-  void validate(ErrorReporter reporter, Map<String, YamlNode> options) {
-    var analyzer = options[AnalyzerOptions.analyzer];
-    if (analyzer is! YamlMap) {
-      return;
-    }
-
-    var v = analyzer.nodes[AnalyzerOptions.strong_mode];
-    if (v is YamlScalar) {
-      var value = toLowerCase(v.value);
-      if (!AnalyzerOptions.trueOrFalse.contains(value)) {
-        trueOrFalseBuilder.reportError(
-            reporter, AnalyzerOptions.strong_mode, v);
-      }
-    }
-  }
-}
-
 /// Validates `analyzer` language configuration options.
 class LanguageOptionValidator extends OptionsValidator {
   ErrorBuilder builder = new ErrorBuilder(AnalyzerOptions.languageOptions);
@@ -313,6 +291,28 @@ class OptionsFileValidator {
   }
 }
 
+/// Validates `analyzer` strong-mode value configuration options.
+class StrongModeOptionValueValidator extends OptionsValidator {
+  ErrorBuilder trueOrFalseBuilder = new TrueOrFalseValueErrorBuilder();
+
+  @override
+  void validate(ErrorReporter reporter, Map<String, YamlNode> options) {
+    var analyzer = options[AnalyzerOptions.analyzer];
+    if (analyzer is! YamlMap) {
+      return;
+    }
+
+    var v = analyzer.nodes[AnalyzerOptions.strong_mode];
+    if (v is YamlScalar) {
+      var value = toLowerCase(v.value);
+      if (!AnalyzerOptions.trueOrFalse.contains(value)) {
+        trueOrFalseBuilder.reportError(
+            reporter, AnalyzerOptions.strong_mode, v);
+      }
+    }
+  }
+}
+
 /// Validates `analyzer` top-level options.
 class TopLevelAnalyzerOptionsValidator extends TopLevelOptionValidator {
   TopLevelAnalyzerOptionsValidator()
@@ -372,7 +372,7 @@ class _OptionsProcessor {
     }
 
     var analyzer = options[AnalyzerOptions.analyzer];
-    if (analyzer is! YamlMap) {
+    if (analyzer is! Map) {
       return;
     }
 
@@ -409,30 +409,36 @@ class _OptionsProcessor {
     context.setConfigurationData(CONFIGURED_ERROR_FILTERS, filters);
   }
 
+  void setLanguageOption(
+      AnalysisContext context, Object feature, Object value) {
+    if (feature == AnalyzerOptions.enableSuperMixins) {
+      if (isTrue(value)) {
+        AnalysisOptionsImpl options =
+            new AnalysisOptionsImpl.from(context.analysisOptions);
+        options.enableSuperMixins = true;
+        context.analysisOptions = options;
+      }
+    }
+    if (feature == AnalyzerOptions.enableGenericMethods) {
+      if (isTrue(value)) {
+        AnalysisOptionsImpl options =
+            new AnalysisOptionsImpl.from(context.analysisOptions);
+        options.enableGenericMethods = true;
+        context.analysisOptions = options;
+      }
+    }
+  }
+
   void setLanguageOptions(AnalysisContext context, Object configs) {
     if (configs is YamlMap) {
       configs.nodes.forEach((k, v) {
-        String feature;
         if (k is YamlScalar && v is YamlScalar) {
-          feature = k.value?.toString();
-          if (feature == AnalyzerOptions.enableSuperMixins) {
-            if (isTrue(v.value)) {
-              AnalysisOptionsImpl options =
-                  new AnalysisOptionsImpl.from(context.analysisOptions);
-              options.enableSuperMixins = true;
-              context.analysisOptions = options;
-            }
-          }
-          if (feature == AnalyzerOptions.enableGenericMethods) {
-            if (isTrue(v.value)) {
-              AnalysisOptionsImpl options =
-                  new AnalysisOptionsImpl.from(context.analysisOptions);
-              options.enableGenericMethods = true;
-              context.analysisOptions = options;
-            }
-          }
+          String feature = k.value?.toString();
+          setLanguageOption(context, feature, v.value);
         }
       });
+    } else if (configs is Map) {
+      configs.forEach((k, v) => setLanguageOption(context, k, v));
     }
   }