Removed fixed dependencies

packages/analyzer/lib/src/context/builder.dart

Index: packages/analyzer/lib/src/context/builder.dart
diff --git a/packages/analyzer/lib/src/context/builder.dart b/packages/analyzer/lib/src/context/builder.dart
new file mode 100644
index 0000000000000000000000000000000000000000..02e1237a2eae93b76517e3a6970c256812e3c5be
--- /dev/null
+++ b/packages/analyzer/lib/src/context/builder.dart
@@ -0,0 +1,600 @@
+// 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.src.context.context_builder;
+
+import 'dart:collection';
+import 'dart:core';
+
+import 'package:analyzer/context/declared_variables.dart';
+import 'package:analyzer/file_system/file_system.dart';
+import 'package:analyzer/plugin/options.dart';
+import 'package:analyzer/plugin/resolver_provider.dart';
+import 'package:analyzer/source/analysis_options_provider.dart';
+import 'package:analyzer/source/package_map_resolver.dart';
+import 'package:analyzer/src/dart/sdk/sdk.dart';
+import 'package:analyzer/src/generated/engine.dart';
+import 'package:analyzer/src/generated/sdk.dart';
+import 'package:analyzer/src/generated/source.dart';
+import 'package:analyzer/src/summary/package_bundle_reader.dart';
+import 'package:analyzer/src/summary/pub_summary.dart';
+import 'package:analyzer/src/task/options.dart';
+import 'package:package_config/packages.dart';
+import 'package:package_config/packages_file.dart';
+import 'package:package_config/src/packages_impl.dart';
+import 'package:path/src/context.dart';
+import 'package:yaml/yaml.dart';
+
+/**
+ * A utility class used to build an analysis context for a given directory.
+ *
+ * The construction of analysis contexts is as follows:
+ *
+ * 1. Determine how package: URI's are to be resolved. This follows the lookup
+ *    algorithm defined by the [package specification][1].
+ *
+ * 2. Using the results of step 1, look in each package for an embedder file
+ *    (_embedder.yaml). If one exists then it defines the SDK. If multiple such
+ *    files exist then use the first one found. Otherwise, use the default SDK.
+ *
+ * 3. Look in each package for an SDK extension file (_sdkext). For each such
+ *    file, add the specified files to the SDK.
+ *
+ * 4. Look for an analysis options file (`analyis_options.yaml` or
+ *    `.analysis_options`) and process the options in the file.
+ *
+ * 5. Create a new context. Initialize its source factory based on steps 1, 2
+ *    and 3. Initialize its analysis options from step 4.
+ *
+ * [1]: https://github.com/dart-lang/dart_enhancement_proposals/blob/master/Accepted/0005%20-%20Package%20Specification/DEP-pkgspec.md.
+ */
+class ContextBuilder {
+  /**
+   * The [ResourceProvider] by which paths are converted into [Resource]s.
+   */
+  final ResourceProvider resourceProvider;
+
+  /**
+   * The manager used to manage the DartSdk's that have been created so that
+   * they can be shared across contexts.
+   */
+  final DartSdkManager sdkManager;
+
+  /**
+   * The cache containing the contents of overlaid files.
+   */
+  final ContentCache contentCache;
+
+  /**
+   * The resolver provider used to create a package: URI resolver, or `null` if
+   * the normal (Package Specification DEP) lookup mechanism is to be used.
+   */
+  ResolverProvider packageResolverProvider;
+
+  /**
+   * The resolver provider used to create a file: URI resolver, or `null` if
+   * the normal file URI resolver is to be used.
+   */
+  ResolverProvider fileResolverProvider;
+
+  /**
+   * The file path of the .packages file that should be used in place of any
+   * file found using the normal (Package Specification DEP) lookup mechanism,
+   * or `null` if the normal lookup mechanism should be used.
+   */
+  String defaultPackageFilePath;
+
+  /**
+   * The file path of the packages directory that should be used in place of any
+   * file found using the normal (Package Specification DEP) lookup mechanism,
+   * or `null` if the normal lookup mechanism should be used.
+   */
+  String defaultPackagesDirectoryPath;
+
+  /**
+   * The file path of the analysis options file that should be used in place of
+   * any file in the root directory or a parent of the root directory, or `null`
+   * if the normal lookup mechanism should be used.
+   */
+  String defaultAnalysisOptionsFilePath;
+
+  /**
+   * The default analysis options that should be used unless some or all of them
+   * are overridden in the analysis options file, or `null` if the default
+   * defaults should be used.
+   */
+  AnalysisOptions defaultOptions;
+
+  /**
+   * A table mapping variable names to values for the declared variables, or
+   * `null` if no additional variables should be declared.
+   */
+  Map<String, String> declaredVariables;
+
+  /**
+   * The manager of pub package summaries.
+   */
+  PubSummaryManager pubSummaryManager;
+
+  /**
+   * Initialize a newly created builder to be ready to build a context rooted in
+   * the directory with the given [rootDirectoryPath].
+   */
+  ContextBuilder(this.resourceProvider, this.sdkManager, this.contentCache);
+
+  /**
+   * Return an analysis context that is configured correctly to analyze code in
+   * the directory with the given [path].
+   *
+   * *Note:* This method is not yet fully implemented and should not be used.
+   */
+  AnalysisContext buildContext(String path) {
+    InternalAnalysisContext context =
+        AnalysisEngine.instance.createAnalysisContext();
+    AnalysisOptions options = getAnalysisOptions(context, path);
+    context.contentCache = contentCache;
+    context.sourceFactory = createSourceFactory(path, options);
+    context.analysisOptions = options;
+    context.name = path;
+    //_processAnalysisOptions(context, optionMap);
+    declareVariables(context);
+    configureSummaries(context);
+    return context;
+  }
+
+  /**
+   * Configure the context to make use of summaries.
+   */
+  void configureSummaries(InternalAnalysisContext context) {
+    if (pubSummaryManager != null) {
+      List<LinkedPubPackage> linkedBundles =
+          pubSummaryManager.getLinkedBundles(context);
+      if (linkedBundles.isNotEmpty) {
+        SummaryDataStore store = new SummaryDataStore([]);
+        for (LinkedPubPackage package in linkedBundles) {
+          store.addBundle(null, package.unlinked);
+          store.addBundle(null, package.linked);
+        }
+        context.resultProvider =
+            new InputPackagesResultProvider(context, store);
+      }
+    }
+  }
+
+  Map<String, List<Folder>> convertPackagesToMap(Packages packages) {
+    Map<String, List<Folder>> folderMap = new HashMap<String, List<Folder>>();
+    if (packages != null && packages != Packages.noPackages) {
+      packages.asMap().forEach((String packageName, Uri uri) {
+        String path = resourceProvider.pathContext.fromUri(uri);
+        folderMap[packageName] = [resourceProvider.getFolder(path)];
+      });
+    }
+    return folderMap;
+  }
+
+//  void _processAnalysisOptions(
+//      AnalysisContext context, Map<String, YamlNode> optionMap) {
+//    List<OptionsProcessor> optionsProcessors =
+//        AnalysisEngine.instance.optionsPlugin.optionsProcessors;
+//    try {
+//      optionsProcessors.forEach(
+//          (OptionsProcessor p) => p.optionsProcessed(context, optionMap));
+//
+//      // Fill in lint rule defaults in case lints are enabled and rules are
+//      // not specified in an options file.
+//      if (context.analysisOptions.lint && !containsLintRuleEntry(optionMap)) {
+//        setLints(context, linterPlugin.contributedRules);
+//      }
+//
+//      // Ask engine to further process options.
+//      if (optionMap != null) {
+//        configureContextOptions(context, optionMap);
+//      }
+//    } on Exception catch (e) {
+//      optionsProcessors.forEach((OptionsProcessor p) => p.onError(e));
+//    }
+//  }
+
+  /**
+   * Return an analysis options object containing the default option values.
+   */
+  AnalysisOptions createDefaultOptions() {
+    if (defaultOptions == null) {
+      return new AnalysisOptionsImpl();
+    }
+    return new AnalysisOptionsImpl.from(defaultOptions);
+  }
+
+  Packages createPackageMap(String rootDirectoryPath) {
+    if (defaultPackageFilePath != null) {
+      File configFile = resourceProvider.getFile(defaultPackageFilePath);
+      List<int> bytes = configFile.readAsBytesSync();
+      Map<String, Uri> map = parse(bytes, configFile.toUri());
+      resolveSymbolicLinks(map);
+      return new MapPackages(map);
+    } else if (defaultPackagesDirectoryPath != null) {
+      Folder folder = resourceProvider.getFolder(defaultPackagesDirectoryPath);
+      return getPackagesFromFolder(folder);
+    }
+    return findPackagesFromFile(rootDirectoryPath);
+  }
+
+  SourceFactory createSourceFactory(
+      String rootDirectoryPath, AnalysisOptions options) {
+    Folder _folder = null;
+    Folder folder() {
+      return _folder ??= resourceProvider.getFolder(rootDirectoryPath);
+    }
+
+    UriResolver fileResolver;
+    if (fileResolverProvider != null) {
+      fileResolver = fileResolverProvider(folder());
+    }
+    fileResolver ??= new ResourceUriResolver(resourceProvider);
+    if (packageResolverProvider != null) {
+      UriResolver packageResolver = packageResolverProvider(folder());
+      if (packageResolver != null) {
+        // TODO(brianwilkerson) This doesn't support either embedder files or
+        // sdk extensions because we don't have a way to get the package map
+        // from the resolver.
+        List<UriResolver> resolvers = <UriResolver>[
+          new DartUriResolver(findSdk(null, options)),
+          packageResolver,
+          fileResolver
+        ];
+        return new SourceFactory(resolvers, null, resourceProvider);
+      }
+    }
+    Packages packages = createPackageMap(rootDirectoryPath);
+    Map<String, List<Folder>> packageMap = convertPackagesToMap(packages);
+    List<UriResolver> resolvers = <UriResolver>[
+      new DartUriResolver(findSdk(packageMap, options)),
+      new PackageMapUriResolver(resourceProvider, packageMap),
+      fileResolver
+    ];
+    return new SourceFactory(resolvers, packages, resourceProvider);
+  }
+
+  /**
+   * Add any [declaredVariables] to the list of declared variables used by the
+   * given [context].
+   */
+  void declareVariables(InternalAnalysisContext context) {
+    if (declaredVariables != null && declaredVariables.isNotEmpty) {
+      DeclaredVariables contextVariables = context.declaredVariables;
+      declaredVariables.forEach((String variableName, String value) {
+        contextVariables.define(variableName, value);
+      });
+    }
+  }
+
+  /**
+   * Finds a package resolution strategy for the directory at the given absolute
+   * [path].
+   *
+   * This function first tries to locate a `.packages` file in the directory. If
+   * that is not found, it instead checks for the presence of a `packages/`
+   * directory in the same place. If that also fails, it starts checking parent
+   * directories for a `.packages` file, and stops if it finds it. Otherwise it
+   * gives up and returns [Packages.noPackages].
+   */
+  Packages findPackagesFromFile(String path) {
+    Resource location = _findPackagesLocation(path);
+    if (location is File) {
+      List<int> fileBytes = location.readAsBytesSync();
+      Map<String, Uri> map =
+          parse(fileBytes, resourceProvider.pathContext.toUri(location.path));
+      resolveSymbolicLinks(map);
+      return new MapPackages(map);
+    } else if (location is Folder) {
+      return getPackagesFromFolder(location);
+    }
+    return Packages.noPackages;
+  }
+
+  /**
+   * Return the SDK that should be used to analyze code. Use the given
+   * [packageMap] and [options] to locate the SDK.
+   */
+  DartSdk findSdk(
+      Map<String, List<Folder>> packageMap, AnalysisOptions options) {
+    if (packageMap != null) {
+      SdkExtensionFinder extFinder = new SdkExtensionFinder(packageMap);
+      List<String> extFilePaths = extFinder.extensionFilePaths;
+      EmbedderYamlLocator locator = new EmbedderYamlLocator(packageMap);
+      Map<Folder, YamlMap> embedderYamls = locator.embedderYamls;
+      EmbedderSdk embedderSdk =
+          new EmbedderSdk(resourceProvider, embedderYamls);
+      if (embedderSdk.sdkLibraries.length > 0) {
+        //
+        // There is an embedder file that defines the content of the SDK and
+        // there might be an extension file that extends it.
+        //
+        List<String> paths = <String>[];
+        for (Folder folder in embedderYamls.keys) {
+          paths.add(folder
+              .getChildAssumingFile(EmbedderYamlLocator.EMBEDDER_FILE_NAME)
+              .path);
+        }
+        paths.addAll(extFilePaths);
+        SdkDescription description = new SdkDescription(paths, options);
+        DartSdk dartSdk = sdkManager.getSdk(description, () {
+          if (extFilePaths.isNotEmpty) {
+            embedderSdk.addExtensions(extFinder.urlMappings);
+          }
+          embedderSdk.analysisOptions = options;
+          embedderSdk.useSummary = sdkManager.canUseSummaries;
+          return embedderSdk;
+        });
+        return dartSdk;
+      } else if (extFilePaths != null && extFilePaths.isNotEmpty) {
+        //
+        // We have an extension file, but no embedder file.
+        //
+        String sdkPath = sdkManager.defaultSdkDirectory;
+        List<String> paths = <String>[sdkPath];
+        paths.addAll(extFilePaths);
+        SdkDescription description = new SdkDescription(paths, options);
+        return sdkManager.getSdk(description, () {
+          FolderBasedDartSdk sdk = new FolderBasedDartSdk(
+              resourceProvider, resourceProvider.getFolder(sdkPath));
+          if (extFilePaths.isNotEmpty) {
+            sdk.addExtensions(extFinder.urlMappings);
+          }
+          sdk.analysisOptions = options;
+          sdk.useSummary = sdkManager.canUseSummaries;
+          return sdk;
+        });
+      }
+    }
+    String sdkPath = sdkManager.defaultSdkDirectory;
+    SdkDescription description = new SdkDescription(<String>[sdkPath], options);
+    return sdkManager.getSdk(description, () {
+      FolderBasedDartSdk sdk = new FolderBasedDartSdk(
+          resourceProvider, resourceProvider.getFolder(sdkPath));
+      sdk.analysisOptions = options;
+      sdk.useSummary = sdkManager.canUseSummaries;
+      return sdk;
+    });
+  }
+
+  /**
+   * Return the analysis options that should be used when the given [context] is
+   * used to analyze code in the directory with the given [path].
+   */
+  AnalysisOptions getAnalysisOptions(AnalysisContext context, String path) {
+    AnalysisOptionsImpl options = createDefaultOptions();
+    File optionsFile = getOptionsFile(path);
+    if (optionsFile != null) {
+      List<OptionsProcessor> optionsProcessors =
+          AnalysisEngine.instance.optionsPlugin.optionsProcessors;
+      try {
+        Map<String, YamlNode> optionMap =
+            new AnalysisOptionsProvider().getOptionsFromFile(optionsFile);
+        optionsProcessors.forEach(
+            (OptionsProcessor p) => p.optionsProcessed(context, optionMap));
+        applyToAnalysisOptions(options, optionMap);
+      } on Exception catch (exception) {
+        optionsProcessors.forEach((OptionsProcessor p) => p.onError(exception));
+      }
+    }
+    return options;
+  }
+
+  /**
+   * Return the analysis options file that should be used when analyzing code in
+   * the directory with the given [path].
+   */
+  File getOptionsFile(String path) {
+    if (defaultAnalysisOptionsFilePath != null) {
+      return resourceProvider.getFile(defaultAnalysisOptionsFilePath);
+    }
+    Folder root = resourceProvider.getFolder(path);
+    for (Folder folder = root; folder != null; folder = folder.parent) {
+      File file =
+          folder.getChildAssumingFile(AnalysisEngine.ANALYSIS_OPTIONS_FILE);
+      if (file.exists) {
+        return file;
+      }
+      file = folder
+          .getChildAssumingFile(AnalysisEngine.ANALYSIS_OPTIONS_YAML_FILE);
+      if (file.exists) {
+        return file;
+      }
+    }
+    return null;
+  }
+
+  /**
+   * Create a [Packages] object for a 'package' directory ([folder]).
+   *
+   * Package names are resolved as relative to sub-directories of the package
+   * directory.
+   */
+  Packages getPackagesFromFolder(Folder folder) {
+    Context pathContext = resourceProvider.pathContext;
+    Map<String, Uri> map = new HashMap<String, Uri>();
+    for (Resource child in folder.getChildren()) {
+      if (child is Folder) {
+        // Inline resolveSymbolicLinks for performance reasons.
+        String packageName = pathContext.basename(child.path);
+        String folderPath = resolveSymbolicLink(child);
+        String uriPath = pathContext.join(folderPath, '.');
+        map[packageName] = pathContext.toUri(uriPath);
+      }
+    }
+    return new MapPackages(map);
+  }
+
+  /**
+   * Resolve any symbolic links encoded in the path to the given [folder].
+   */
+  String resolveSymbolicLink(Folder folder) {
+    try {
+      return folder.resolveSymbolicLinksSync().path;
+    } on FileSystemException {
+      return folder.path;
+    }
+  }
+
+  /**
+   * Resolve any symbolic links encoded in the URI's in the given [map] by
+   * replacing the values in the map.
+   */
+  void resolveSymbolicLinks(Map<String, Uri> map) {
+    Context pathContext = resourceProvider.pathContext;
+    for (String packageName in map.keys) {
+      Folder folder =
+          resourceProvider.getFolder(pathContext.fromUri(map[packageName]));
+      String folderPath = resolveSymbolicLink(folder);
+      // Add a '.' so that the URI is suitable for resolving relative URI's
+      // against it.
+      String uriPath = pathContext.join(folderPath, '.');
+      map[packageName] = pathContext.toUri(uriPath);
+    }
+  }
+
+  /**
+   * Find the location of the package resolution file/directory for the
+   * directory at the given absolute [path].
+   *
+   * Checks for a `.packages` file in the [path]. If not found,
+   * checks for a `packages` directory in the same directory. If still not
+   * found, starts checking parent directories for `.packages` until reaching
+   * the root directory.
+   *
+   * Return a [File] object representing a `.packages` file if one is found, a
+   * [Folder] object for the `packages/` directory if that is found, or `null`
+   * if neither is found.
+   */
+  Resource _findPackagesLocation(String path) {
+    Folder folder = resourceProvider.getFolder(path);
+    if (!folder.exists) {
+      throw new ArgumentError.value(path, "path", "Directory does not exist.");
+    }
+    File checkForConfigFile(Folder folder) {
+      File file = folder.getChildAssumingFile('.packages');
+      if (file.exists) {
+        return file;
+      }
+      return null;
+    }
+
+    // Check for $cwd/.packages
+    File packagesCfgFile = checkForConfigFile(folder);
+    if (packagesCfgFile != null) {
+      return packagesCfgFile;
+    }
+    // Check for $cwd/packages/
+    Folder packagesDir = folder.getChildAssumingFolder("packages");
+    if (packagesDir.exists) {
+      return packagesDir;
+    }
+    // Check for cwd(/..)+/.packages
+    Folder parentDir = folder.parent;
+    while (parentDir != null) {
+      packagesCfgFile = checkForConfigFile(parentDir);
+      if (packagesCfgFile != null) {
+        return packagesCfgFile;
+      }
+      parentDir = parentDir.parent;
+    }
+    return null;
+  }
+}
+
+/**
+ * Given a package map, check in each package's lib directory for the existence
+ * of an `_embedder.yaml` file. If the file contains a top level YamlMap, it
+ * will be added to the [embedderYamls] map.
+ */
+class EmbedderYamlLocator {
+  /**
+   * The name of the embedder files being searched for.
+   */
+  static const String EMBEDDER_FILE_NAME = '_embedder.yaml';
+
+  /**
+   * A mapping from a package's library directory to the parsed YamlMap.
+   */
+  final Map<Folder, YamlMap> embedderYamls = new HashMap<Folder, YamlMap>();
+
+  /**
+   * Initialize a newly created locator by processing the packages in the given
+   * [packageMap].
+   */
+  EmbedderYamlLocator(Map<String, List<Folder>> packageMap) {
+    if (packageMap != null) {
+      _processPackageMap(packageMap);
+    }
+  }
+
+  /**
+   * Programmatically add an `_embedder.yaml` mapping.
+   */
+  void addEmbedderYaml(Folder libDir, String embedderYaml) {
+    _processEmbedderYaml(libDir, embedderYaml);
+  }
+
+  /**
+   * Refresh the map of located files to those found by processing the given
+   * [packageMap].
+   */
+  void refresh(Map<String, List<Folder>> packageMap) {
+    // Clear existing.
+    embedderYamls.clear();
+    if (packageMap != null) {
+      _processPackageMap(packageMap);
+    }
+  }
+
+  /**
+   * Given the yaml for an embedder ([embedderYaml]) and a folder ([libDir]),
+   * setup the uri mapping.
+   */
+  void _processEmbedderYaml(Folder libDir, String embedderYaml) {
+    try {
+      YamlNode yaml = loadYaml(embedderYaml);
+      if (yaml is YamlMap) {
+        embedderYamls[libDir] = yaml;
+      }
+    } catch (_) {
+      // Ignored
+    }
+  }
+
+  /**
+   * Given a package [name] and a list of folders ([libDirs]), process any
+   * `_embedder.yaml` files that are found in any of the folders.
+   */
+  void _processPackage(String name, List<Folder> libDirs) {
+    for (Folder libDir in libDirs) {
+      String embedderYaml = _readEmbedderYaml(libDir);
+      if (embedderYaml != null) {
+        _processEmbedderYaml(libDir, embedderYaml);
+      }
+    }
+  }
+
+  /**
+   * Process each of the entries in the [packageMap].
+   */
+  void _processPackageMap(Map<String, List<Folder>> packageMap) {
+    packageMap.forEach(_processPackage);
+  }
+
+  /**
+   * Read and return the contents of [libDir]/[EMBEDDER_FILE_NAME], or `null` if
+   * the file doesn't exist.
+   */
+  String _readEmbedderYaml(Folder libDir) {
+    File file = libDir.getChild(EMBEDDER_FILE_NAME);
+    try {
+      return file.readAsStringSync();
+    } on FileSystemException {
+      // File can't be read.
+      return null;
+    }
+  }
+}