Index: mojo/public/dart/third_party/analyzer/lib/source/package_map_resolver.dart |
diff --git a/mojo/public/dart/third_party/analyzer/lib/source/package_map_resolver.dart b/mojo/public/dart/third_party/analyzer/lib/source/package_map_resolver.dart |
new file mode 100644 |
index 0000000000000000000000000000000000000000..0fa12ae05c2ab484894a89dffcb0fac6ec881852 |
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+++ b/mojo/public/dart/third_party/analyzer/lib/source/package_map_resolver.dart |
@@ -0,0 +1,137 @@ |
+// Copyright (c) 2014, 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 source.package_map_resolver; |
+ |
+import 'dart:core' hide Resource; |
+ |
+import 'package:analyzer/file_system/file_system.dart'; |
+import 'package:analyzer/src/generated/source.dart'; |
+import 'package:analyzer/src/util/asserts.dart' as asserts; |
+import 'package:path/path.dart' as pathos; |
+ |
+/** |
+ * A [UriResolver] implementation for the `package:` scheme that uses a map of |
+ * package names to their directories. |
+ */ |
+class PackageMapUriResolver extends UriResolver { |
+ /** |
+ * The name of the `package` scheme. |
+ */ |
+ static const String PACKAGE_SCHEME = "package"; |
+ |
+ /** |
+ * A table mapping package names to the path of the directories containing |
+ * the package. |
+ */ |
+ final Map<String, List<Folder>> packageMap; |
+ |
+ /** |
+ * The [ResourceProvider] for this resolver. |
+ */ |
+ final ResourceProvider resourceProvider; |
+ |
+ /** |
+ * Create a new [PackageMapUriResolver]. |
+ * |
+ * [packageMap] is a table mapping package names to the paths of the |
+ * directories containing the package |
+ */ |
+ PackageMapUriResolver(this.resourceProvider, this.packageMap) { |
+ asserts.notNull(resourceProvider); |
+ asserts.notNull(packageMap); |
+ } |
+ |
+ @override |
+ Source resolveAbsolute(Uri uri, [Uri actualUri]) { |
+ if (!isPackageUri(uri)) { |
+ return null; |
+ } |
+ // Prepare path. |
+ String path = uri.path; |
+ // Prepare path components. |
+ int index = path.indexOf('/'); |
+ if (index == -1 || index == 0) { |
+ return null; |
+ } |
+ // <pkgName>/<relPath> |
+ String pkgName = path.substring(0, index); |
+ String relPath = path.substring(index + 1); |
+ // Try to find an existing file. |
+ List<Folder> packageDirs = packageMap[pkgName]; |
+ if (packageDirs != null) { |
+ for (Folder packageDir in packageDirs) { |
+ if (packageDir.exists) { |
+ Resource result = packageDir.getChild(relPath); |
+ if (result is File && result.exists) { |
+ return result.createSource(uri); |
+ } |
+ } |
+ } |
+ } |
+ // Return a NonExistingSource instance. |
+ // This helps provide more meaningful error messages to users |
+ // (a missing file error, as opposed to an invalid URI error). |
+ String fullPath = packageDirs != null && packageDirs.isNotEmpty |
+ ? packageDirs.first.canonicalizePath(relPath) |
+ : relPath; |
+ return new NonExistingSource(fullPath, uri, UriKind.PACKAGE_URI); |
+ } |
+ |
+ @override |
+ Uri restoreAbsolute(Source source) { |
+ String sourcePath = source.fullName; |
+ Uri bestMatch; |
+ int bestMatchLength = -1; |
+ pathos.Context pathContext = resourceProvider.pathContext; |
+ for (String pkgName in packageMap.keys) { |
+ List<Folder> pkgFolders = packageMap[pkgName]; |
+ for (int i = 0; i < pkgFolders.length; i++) { |
+ Folder pkgFolder = pkgFolders[i]; |
+ String pkgFolderPath = pkgFolder.path; |
+ if (pkgFolderPath.length > bestMatchLength && |
+ sourcePath.startsWith(pkgFolderPath + pathContext.separator)) { |
+ String relPath = sourcePath.substring(pkgFolderPath.length + 1); |
+ if (_isReversibleTranslation(pkgFolders, i, relPath)) { |
+ List<String> relPathComponents = pathContext.split(relPath); |
+ String relUriPath = pathos.posix.joinAll(relPathComponents); |
+ bestMatch = Uri.parse('$PACKAGE_SCHEME:$pkgName/$relUriPath'); |
+ bestMatchLength = pkgFolderPath.length; |
+ } |
+ } |
+ } |
+ } |
+ return bestMatch; |
+ } |
+ |
+ /** |
+ * A translation from file path to package URI has just been found for |
+ * using the [packageDirIndex]th element of [packageDirs], and appending the |
+ * relative path [relPath]. Determine whether the translation is reversible; |
+ * that is, whether translating the package URI pack to a file path will |
+ * produce the file path we started with. |
+ */ |
+ bool _isReversibleTranslation( |
+ List<Folder> packageDirs, int packageDirIndex, String relPath) { |
+ // The translation is reversible provided there is no prior element of |
+ // [packageDirs] containing a file matching [relPath]. |
+ for (int i = 0; i < packageDirIndex; i++) { |
+ Folder packageDir = packageDirs[i]; |
+ if (packageDir.exists) { |
+ Resource result = packageDir.getChild(relPath); |
+ if (result is File && result.exists) { |
+ return false; |
+ } |
+ } |
+ } |
+ return true; |
+ } |
+ |
+ /** |
+ * Returns `true` if [uri] is a `package` URI. |
+ */ |
+ static bool isPackageUri(Uri uri) { |
+ return uri.scheme == PACKAGE_SCHEME; |
+ } |
+} |