Removed fixed dependencies

packages/analyzer/lib/source/analysis_options_provider.dart

Index: packages/analyzer/lib/source/analysis_options_provider.dart
diff --git a/packages/analyzer/lib/source/analysis_options_provider.dart b/packages/analyzer/lib/source/analysis_options_provider.dart
index aeac0531ecd0900f04baa9823592b8be49697002..cdd912cc3d5c41680c0ae3e3165b8fd8236a2619 100644
--- a/packages/analyzer/lib/source/analysis_options_provider.dart
+++ b/packages/analyzer/lib/source/analysis_options_provider.dart
@@ -2,20 +2,36 @@
 // 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 source.analysis_options_provider;
+library analyzer.source.analysis_options_provider;
+
+import 'dart:core';
 
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/src/generated/engine.dart';
+import 'package:analyzer/src/util/yaml.dart';
+import 'package:source_span/source_span.dart';
 import 'package:yaml/yaml.dart';
 
-/// Provide the options found in the `.analysis_options` file.
+/// Provide the options found in the analysis options file.
 class AnalysisOptionsProvider {
-  /// Provide the options found in [root]/[ANALYSIS_OPTIONS_FILE].
+  /// Provide the options found in either
+  /// [root]/[AnalysisEngine.ANALYSIS_OPTIONS_FILE] or
+  /// [root]/[AnalysisEngine.ANALYSIS_OPTIONS_YAML_FILE].
   /// Return an empty options map if the file does not exist.
-  Map<String, YamlNode> getOptions(Folder root) {
-    var optionsSource = _readAnalysisOptionsFile(
-        root.getChild(AnalysisEngine.ANALYSIS_OPTIONS_FILE));
-    return getOptionsFromString(optionsSource);
+  Map<String, YamlNode> getOptions(Folder root, {bool crawlUp: false}) {
+    Resource resource;
+    for (Folder folder = root; folder != null; folder = folder.parent) {
+      resource = folder.getChild(AnalysisEngine.ANALYSIS_OPTIONS_FILE);
+      if (resource.exists) {
+        break;
+      }
+      resource = folder.getChild(AnalysisEngine.ANALYSIS_OPTIONS_YAML_FILE);
+      if (resource.exists || !crawlUp) {
+        break;
+      }
+    }
+    String optionsText = _readAnalysisOptionsFile(resource);
+    return getOptionsFromString(optionsText);
   }
 
   /// Provide the options found in [file].
@@ -28,30 +44,72 @@ class AnalysisOptionsProvider {
   /// Provide the options found in [optionsSource].
   /// Return an empty options map if the source is null.
   Map<String, YamlNode> getOptionsFromString(String optionsSource) {
-    var options = <String, YamlNode>{};
+    Map<String, YamlNode> options = <String, YamlNode>{};
     if (optionsSource == null) {
       return options;
     }
-    var doc = loadYaml(optionsSource);
+
+    YamlNode safelyLoadYamlNode() {
+      try {
+        return loadYamlNode(optionsSource);
+      } on YamlException catch (e) {
+        throw new OptionsFormatException(e.message, e.span);
+      } catch (e) {
+        throw new OptionsFormatException('Unable to parse YAML document.');
+      }
+    }
+
+    YamlNode doc = safelyLoadYamlNode();
+
+    // Empty options.
+    if (doc is YamlScalar && doc.value == null) {
+      return options;
+    }
     if ((doc != null) && (doc is! YamlMap)) {
-      throw new Exception(
-          'Bad options file format (expected map, got ${doc.runtimeType})\n'
-          'contents of options file:\n'
-          '$optionsSource\n');
+      throw new OptionsFormatException(
+          'Bad options file format (expected map, got ${doc.runtimeType})',
+          doc.span);
     }
     if (doc is YamlMap) {
-      doc.forEach((k, v) {
-        if (k is! String) {
-          throw new Exception(
+      doc.nodes.forEach((k, YamlNode v) {
+        var key;
+        if (k is YamlScalar) {
+          key = k.value;
+        }
+        if (key is! String) {
+          throw new OptionsFormatException(
               'Bad options file format (expected String scope key, '
-              'got ${k.runtimeType})');
+              'got ${k.runtimeType})',
+              (k ?? doc).span);
         }
-        options[k] = v;
+        if (v != null && v is! YamlNode) {
+          throw new OptionsFormatException(
+              'Bad options file format (expected Node value, '
+              'got ${v.runtimeType}: `${v.toString()}`)',
+              doc.span);
+        }
+        options[key] = v;
       });
     }
     return options;
   }
 
+  /// Merge the given options contents where the values in [defaults] may be
+  /// overridden by [overrides].
+  ///
+  /// Some notes about merge semantics:
+  ///
+  ///   * lists are merged (without duplicates).
+  ///   * lists of scalar values can be promoted to simple maps when merged with
+  ///     maps of strings to booleans (e.g., ['opt1', 'opt2'] becomes
+  ///     {'opt1': true, 'opt2': true}.
+  ///   * maps are merged recursively.
+  ///   * if map values cannot be merged, the overriding value is taken.
+  ///
+  Map<String, YamlNode> merge(
+          Map<String, YamlNode> defaults, Map<String, YamlNode> overrides) =>
+      new Merger().merge(defaults, overrides) as Map<String, YamlNode>;
+
   /// Read the contents of [file] as a string.
   /// Returns null if file does not exist.
   String _readAnalysisOptionsFile(File file) {
@@ -63,3 +121,14 @@ class AnalysisOptionsProvider {
     }
   }
 }
+
+/// Thrown on options format exceptions.
+class OptionsFormatException implements Exception {
+  final String message;
+  final SourceSpan span;
+  OptionsFormatException(this.message, [this.span]);
+
+  @override
+  String toString() =>
+      'OptionsFormatException: ${message?.toString()}, ${span?.toString()}';
+}