simplify EmbedderUrlResolver

pkg/analyzer/lib/source/embedder.dart

Index: pkg/analyzer/lib/source/embedder.dart
diff --git a/pkg/analyzer/lib/source/embedder.dart b/pkg/analyzer/lib/source/embedder.dart
index 5874d4f9873a5f67fc4f0e6d391590c03d063b75..5e111f4bc0a2f465d5dc9e93abc44ce18fbb434b 100644
--- a/pkg/analyzer/lib/source/embedder.dart
+++ b/pkg/analyzer/lib/source/embedder.dart
@@ -16,7 +16,6 @@ import 'package:analyzer/src/generated/java_io.dart' show JavaFile;
 import 'package:analyzer/src/generated/sdk.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/generated/source_io.dart' show FileBasedSource;
-import 'package:path/path.dart' as pathos;
 import 'package:yaml/yaml.dart';
 
 const String _DART_COLON_PREFIX = 'dart:';
@@ -116,8 +115,8 @@ class EmbedderUriResolver extends DartUriResolver {
   /// Construct a [EmbedderUriResolver] from a package map
   /// (see [PackageMapProvider]).
   EmbedderUriResolver(Map<Folder, YamlMap> embedderYamls)
-      : super(new _EmbedderSdk()) {
-    (dartSdk as _EmbedderSdk)._resolver = this;
+      : super(new EmbedderSdk()) {
+    (dartSdk as EmbedderSdk)._resolver = this;
     if (embedderYamls == null) {
       return;
     }
@@ -144,105 +143,25 @@ class EmbedderUriResolver extends DartUriResolver {
       // _embedder.yaml file in libDir.
       return;
     }
-    String key = name;
-    String value = libDir.canonicalizePath(file);
-    _urlMappings[key] = value;
+    String libPath = libDir.canonicalizePath(file);
+    _urlMappings[name] = libPath;
     String shortName = name.substring(_DART_COLON_PREFIX.length);
     SdkLibraryImpl library = new SdkLibraryImpl(shortName);
-    library.path = value;
-    (dartSdk as _EmbedderSdk)._librariesMap.setLibrary(name, library);
+    library.path = libPath;
+    (dartSdk as EmbedderSdk)._librariesMap.setLibrary(name, library);
   }
 
   /// Number of embedder libraries.
   int get length => _urlMappings.length;
 
-  /// Return the path mapping for [libName] or null if there is none.
-  String operator [](String libName) => _urlMappings[libName];
-
-  @override
-  Source resolveAbsolute(Uri importUri, [Uri actualUri]) {
-    String libraryName = _libraryName(importUri);
-    String partPath = _partPath(importUri);
-    // Lookup library name in mappings.
-    String mapping = _urlMappings[libraryName];
-    if (mapping == null) {
-      // Not found.
-      return null;
-    }
-    // This mapping points to the main entry file of the dart: library.
-    Uri libraryEntry = new Uri.file(mapping);
-    if (!libraryEntry.isAbsolute) {
-      // We expect an absolute path.
-      return null;
-    }
-
-    if (partPath != null) {
-      return _resolvePart(libraryEntry, partPath, importUri);
-    } else {
-      return _resolveEntry(libraryEntry, importUri);
-    }
-  }
-
   @override
   Uri restoreAbsolute(Source source) {
-    String extensionName = _findExtensionNameFor(source.fullName);
-    if (extensionName != null) {
-      return Uri.parse(extensionName);
-    }
-    // TODO(johnmccutchan): Handle restoring parts.
-    return null;
-  }
-
-  /// Return the extension name for [fullName] or `null`.
-  String _findExtensionNameFor(String fullName) {
-    String result;
-    _urlMappings.forEach((extensionName, pathMapping) {
-      if (pathMapping == fullName) {
-        result = extensionName;
-      }
-    });
-    return result;
-  }
-
-  /// Return the library name of [importUri].
-  String _libraryName(Uri importUri) {
-    String uri = importUri.toString();
-    int index = uri.indexOf('/');
-    if (index >= 0) {
-      return uri.substring(0, index);
-    }
-    return uri;
-  }
-
-  /// Return the part path of [importUri].
-  String _partPath(Uri importUri) {
-    String uri = importUri.toString();
-    int index = uri.indexOf('/');
-    if (index >= 0) {
-      return uri.substring(index + 1);
-    }
-    return null;
-  }
-
-  /// Resolve an import of an sdk extension.
-  Source _resolveEntry(Uri libraryEntry, Uri importUri) {
-    // Library entry.
-    JavaFile javaFile = new JavaFile.fromUri(libraryEntry);
-    return new FileBasedSource(javaFile, importUri);
-  }
-
-  /// Resolve a 'part' statement inside an sdk extension.
-  Source _resolvePart(Uri libraryEntry, String partPath, Uri importUri) {
-    // Library part.
-    String directory = pathos.dirname(libraryEntry.path);
-    Uri partUri = new Uri.file(pathos.join(directory, partPath));
-    assert(partUri.isAbsolute);
-    JavaFile javaFile = new JavaFile.fromUri(partUri);
-    return new FileBasedSource(javaFile, importUri);
+    Source sdkSource = dartSdk.fromFileUri(Uri.parse(source.fullName));
+    return sdkSource?.uri;
   }
 }
 
-class _EmbedderSdk implements DartSdk {
+class EmbedderSdk implements DartSdk {
   // TODO(danrubel) Refactor this with DirectoryBasedDartSdk
 
   /// The resolver associated with this embedder sdk.
@@ -285,12 +204,11 @@ class _EmbedderSdk implements DartSdk {
   Source fromFileUri(Uri uri) {
     JavaFile file = new JavaFile.fromUri(uri);
     String filePath = file.getAbsolutePath();
-    String srcPath = filePath.replaceAll('\\', '/');
 
     String path;
     for (SdkLibrary library in _librariesMap.sdkLibraries) {
       String libraryPath = library.path;
-      if (srcPath == libraryPath) {
+      if (filePath == libraryPath) {
         path = '$_DART_COLON_PREFIX${library.shortName}';
         break;
       }
@@ -303,10 +221,10 @@ class _EmbedderSdk implements DartSdk {
           continue;
         }
         String prefix = libraryPath.substring(0, index + 1);
-        if (!srcPath.startsWith(prefix)) {
+        if (!filePath.startsWith(prefix)) {
           continue;
         }
-        var relPath = srcPath.substring(prefix.length);
+        var relPath = filePath.substring(prefix.length);
         path = '$_DART_COLON_PREFIX${library.shortName}/$relPath';
         break;
       }