Option support for `enableSuperMixins` (and more).

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

Index: pkg/analyzer/lib/src/task/options.dart
diff --git a/pkg/analyzer/lib/src/task/options.dart b/pkg/analyzer/lib/src/task/options.dart
index fb24b0e47215d0cb05f50ad98b271aa13197130c..689bff2eebbd5b212bf0decb42562883051f97a4 100644
--- a/pkg/analyzer/lib/src/task/options.dart
+++ b/pkg/analyzer/lib/src/task/options.dart
@@ -10,6 +10,7 @@ import 'package:analyzer/source/analysis_options_provider.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/java_engine.dart';
 import 'package:analyzer/src/generated/source.dart';
+import 'package:analyzer/src/generated/utilities_general.dart';
 import 'package:analyzer/src/task/general.dart';
 import 'package:analyzer/task/general.dart';
 import 'package:analyzer/task/model.dart';
@@ -23,11 +24,21 @@ final ListResultDescriptor<AnalysisError> ANALYSIS_OPTIONS_ERRORS =
     new ListResultDescriptor<AnalysisError>(
         'ANALYSIS_OPTIONS_ERRORS', AnalysisError.NO_ERRORS);
 
+final _OptionsProcessor _processor = new _OptionsProcessor();
+
+/// Configure this [context] based on configuration details specified in
+/// the given [options].
+void configureContextOptions(
+        AnalysisContext context, Map<String, YamlNode> options) =>
+    _processor.configure(context, options);
+
 /// `analyzer` analysis options constants.
 class AnalyzerOptions {
   static const String analyzer = 'analyzer';
+  static const String enableSuperMixins = 'enableSuperMixins';
   static const String errors = 'errors';
   static const String exclude = 'exclude';
+  static const String language = 'language';
   static const String plugins = 'plugins';
   static const String strong_mode = 'strong-mode';
 
@@ -37,13 +48,69 @@ class AnalyzerOptions {
   /// Ways to say `include`.
   static const List<String> includeSynonyms = const ['include', 'true'];
 
+  /// Ways to say `true` or `false`.
+  static const List<String> trueOrFalse = const ['true', 'false'];
+
   /// Supported top-level `analyzer` options.
-  static const List<String> top_level = const [
+  static const List<String> topLevel = const [
     errors,
     exclude,
+    language,
     plugins,
     strong_mode
   ];
+
+  /// Supported `analyzer` language configuration options.
+  static const List<String> languageOptions = const [enableSuperMixins];
+}
+
+/// Validates `analyzer` options.
+class AnalyzerOptionsValidator extends CompositeValidator {
+  AnalyzerOptionsValidator()
+      : super([
+          new TopLevelAnalyzerOptionsValidator(),
+          new ErrorFilterOptionValidator(),
+          new LanguageOptionValidator()
+        ]);
+}
+
+/// Convenience class for composing validators.
+class CompositeValidator extends OptionsValidator {
+  final List<OptionsValidator> validators;
+  CompositeValidator(this.validators);
+
+  @override
+  void validate(ErrorReporter reporter, Map<String, YamlNode> options) =>
+      validators.forEach((v) => v.validate(reporter, options));
+}
+
+/// Builds error reports with value proposals.
+class ErrorBuilder {
+  String proposal;
+  AnalysisOptionsWarningCode code;
+
+  /// Create a builder for the given [supportedOptions].
+  ErrorBuilder(List<String> supportedOptions) {
+    assert(supportedOptions != null && !supportedOptions.isEmpty);
+    if (supportedOptions.length > 1) {
+      proposal = StringUtilities.printListOfQuotedNames(supportedOptions);
+      code = pluralProposalCode;
+    } else {
+      proposal = "'${supportedOptions.join()}'";
+      code = singularProposalCode;
+    }
+  }
+  AnalysisOptionsWarningCode get pluralProposalCode =>
+      AnalysisOptionsWarningCode.UNSUPPORTED_OPTION_WITH_LEGAL_VALUES;
+
+  AnalysisOptionsWarningCode get singularProposalCode =>
+      AnalysisOptionsWarningCode.UNSUPPORTED_OPTION_WITH_LEGAL_VALUE;
+
+  /// Report an unsupported [node] value, defined in the given [scopeName].
+  void reportError(ErrorReporter reporter, String scopeName, YamlNode node) {
+    reporter.reportErrorForSpan(
+        code, node.span, [scopeName, node.value, proposal]);
+  }
 }
 
 /// Validates `analyzer` error filter options.
@@ -57,17 +124,15 @@ class ErrorFilterOptionValidator extends OptionsValidator {
   void validate(ErrorReporter reporter, Map<String, YamlNode> options) {
     YamlMap analyzer = options[AnalyzerOptions.analyzer];
     if (analyzer == null) {
-      // No options for analyzer.
       return;
     }
 
     YamlNode filters = analyzer[AnalyzerOptions.errors];
-
     if (filters is YamlMap) {
       String value;
       filters.nodes.forEach((k, v) {
         if (k is YamlScalar) {
-          value = k.value?.toString()?.toUpperCase();
+          value = toUpperCase(k.value);
           if (!ErrorCode.values.any((ErrorCode code) => code.name == value)) {
             reporter.reportErrorForSpan(
                 AnalysisOptionsWarningCode.UNRECOGNIZED_ERROR_CODE,
@@ -76,7 +141,7 @@ class ErrorFilterOptionValidator extends OptionsValidator {
           }
         }
         if (v is YamlScalar) {
-          value = v.value?.toString()?.toLowerCase();
+          value = toLowerCase(v.value);
           if (!AnalyzerOptions.ignoreSynonyms.contains(value) &&
               !AnalyzerOptions.includeSynonyms.contains(value)) {
             reporter.reportErrorForSpan(
@@ -84,39 +149,12 @@ class ErrorFilterOptionValidator extends OptionsValidator {
                 v.span,
                 [AnalyzerOptions.errors, v.value?.toString(), legalIncludes]);
           }
-
-          value = v.value?.toString()?.toLowerCase();
         }
       });
     }
   }
 }
 
-/// Validates `analyzer` top-level options.
-class TopLevelAnalyzerOptionsValidator extends TopLevelOptionValidator {
-  TopLevelAnalyzerOptionsValidator()
-      : super(AnalyzerOptions.analyzer, AnalyzerOptions.top_level);
-}
-
-/// Validates `analyzer` options.
-class AnalyzerOptionsValidator extends CompositeValidator {
-  AnalyzerOptionsValidator()
-      : super([
-          new TopLevelAnalyzerOptionsValidator(),
-          new ErrorFilterOptionValidator()
-        ]);
-}
-
-/// Convenience class for composing validators.
-class CompositeValidator extends OptionsValidator {
-  final List<OptionsValidator> validators;
-  CompositeValidator(this.validators);
-
-  @override
-  void validate(ErrorReporter reporter, Map<String, YamlNode> options) =>
-      validators.forEach((v) => v.validate(reporter, options));
-}
-
 /// A task that generates errors for an `.analysis_options` file.
 class GenerateOptionsErrorsTask extends SourceBasedAnalysisTask {
   /// The name of the input whose value is the content of the file.
@@ -184,6 +222,43 @@ class GenerateOptionsErrorsTask extends SourceBasedAnalysisTask {
       new GenerateOptionsErrorsTask(context, target);
 }
 
+/// Validates `analyzer` language configuration options.
+class LanguageOptionValidator extends OptionsValidator {
+  ErrorBuilder builder = new ErrorBuilder(AnalyzerOptions.languageOptions);
+  ErrorBuilder trueOrFalseBuilder = new TrueOrFalseValueErrorBuilder();
+
+  @override
+  void validate(ErrorReporter reporter, Map<String, YamlNode> options) {
+    YamlMap analyzer = options[AnalyzerOptions.analyzer];
+    if (analyzer == null) {
+      return;
+    }
+
+    YamlNode language = analyzer[AnalyzerOptions.language];
+    if (language is YamlMap) {
+      language.nodes.forEach((k, v) {
+        String key, value;
+        bool validKey = false;
+        if (k is YamlScalar) {
+          key = k.value?.toString();
+          if (!AnalyzerOptions.languageOptions.contains(key)) {
+            builder.reportError(reporter, AnalyzerOptions.language, k);
+          } else {
+            // If we have a valid key, go on and check the value.
+            validKey = true;
+          }
+        }
+        if (validKey && v is YamlScalar) {
+          value = toLowerCase(v.value);
+          if (!AnalyzerOptions.trueOrFalse.contains(value)) {
+            trueOrFalseBuilder.reportError(reporter, key, v);
+          }
+        }
+      });
+    }
+  }
+}
+
 /// Validates `linter` top-level options.
 /// TODO(pq): move into `linter` package and plugin.
 class LinterOptionsValidator extends TopLevelOptionValidator {
@@ -211,6 +286,12 @@ class OptionsFileValidator {
   }
 }
 
+/// Validates `analyzer` top-level options.
+class TopLevelAnalyzerOptionsValidator extends TopLevelOptionValidator {
+  TopLevelAnalyzerOptionsValidator()
+      : super(AnalyzerOptions.analyzer, AnalyzerOptions.topLevel);
+}
+
 /// Validates top-level options. For example,
 ///     plugin:
 ///       top-level-option: true
@@ -248,3 +329,84 @@ class TopLevelOptionValidator extends OptionsValidator {
     }
   }
 }
+
+/// An error-builder that knows about `true` and `false` legal values.
+class TrueOrFalseValueErrorBuilder extends ErrorBuilder {
+  TrueOrFalseValueErrorBuilder() : super(AnalyzerOptions.trueOrFalse);
+  @override
+  AnalysisOptionsWarningCode get pluralProposalCode =>
+      AnalysisOptionsWarningCode.UNSUPPORTED_VALUE;
+}
+
+class _OptionsProcessor {
+  void configure(AnalysisContext context, Map<String, YamlNode> options) {
+    if (options == null) {
+      return;
+    }
+
+    YamlMap analyzer = options[AnalyzerOptions.analyzer];
+    if (analyzer == null) {
+      return;
+    }
+
+    // Set strong mode (default is false).
+    bool strongMode = analyzer[AnalyzerOptions.strong_mode] ?? false;
+    setStrongMode(context, strongMode);
+
+    // Set filters.
+    YamlNode filters = analyzer[AnalyzerOptions.errors];
+    setFilters(context, filters);
+
+    // Process language options.
+    YamlNode language = analyzer[AnalyzerOptions.language];
+    setLanguageOptions(context, language);
+  }
+
+  void setFilters(AnalysisContext context, YamlNode codes) {
+    List<ErrorFilter> filters = <ErrorFilter>[];
+    // If codes are enumerated, collect them as filters; else leave filters
+    // empty to overwrite previous value.
+    if (codes is YamlMap) {
+      String value;
+      codes.nodes.forEach((k, v) {
+        if (k is YamlScalar && v is YamlScalar) {
+          value = toLowerCase(v.value);
+          if (AnalyzerOptions.ignoreSynonyms.contains(value)) {
+            // Case-insensitive.
+            String code = toUpperCase(k.value);
+            filters.add((AnalysisError error) => error.errorCode.name == code);
+          }
+        }
+      });
+    }
+    context.setConfigurationData(CONFIGURED_ERROR_FILTERS, filters);
+  }
+
+  void setLanguageOptions(AnalysisContext context, YamlNode 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;
+            }
+          }
+        }
+      });
+    }
+  }
+
+  void setStrongMode(AnalysisContext context, bool strongMode) {
+    if (context.analysisOptions.strongMode != strongMode) {
+      AnalysisOptionsImpl options =
+          new AnalysisOptionsImpl.from(context.analysisOptions);
+      options.strongMode = strongMode;
+      context.analysisOptions = options;
+    }
+  }
+}