Handle relative paths in the output of "pub list-package-dirs".

pkg/analysis_server/lib/src/resource.dart

Index: pkg/analysis_server/lib/src/resource.dart
diff --git a/pkg/analysis_server/lib/src/resource.dart b/pkg/analysis_server/lib/src/resource.dart
index f5e5b7bd6b894efef893b747561717bbbb5aaa61..d988769a970eb06f99e0bb04d975ea1b08851b1d 100644
--- a/pkg/analysis_server/lib/src/resource.dart
+++ b/pkg/analysis_server/lib/src/resource.dart
@@ -47,6 +47,16 @@ abstract class Folder extends Resource {
    * folders, including folders reachable via links).
    */
   Stream<WatchEvent> get changes;
+
+  /**
+   * If the path [path] is a relative path, convert it to an absolute path
+   * by interpreting it relative to this folder.  If it is already an aboslute
+   * path, then don't change it.
+   *
+   * However, regardless of whether [path] is relative or absolute, normalize
+   * it by removing path components of the form '.' or '..'.
+   */
+  String canonicalizePath(String path);
 }
 
 
@@ -238,9 +248,7 @@ class _MemoryFolder extends _MemoryResource implements Folder {
       super(provider, path);
   @override
   Resource getChild(String relPath) {
-    relPath = posix.normalize(relPath);
-    String childPath = posix.join(path, relPath);
-    childPath = posix.normalize(childPath);
+    String childPath = canonicalizePath(relPath);
     _MemoryResource resource = _provider._pathToResource[childPath];
     if (resource == null) {
       resource = new _MemoryFile(_provider, childPath);
@@ -274,6 +282,14 @@ class _MemoryFolder extends _MemoryResource implements Folder {
     });
     return streamController.stream;
   }
+
+  @override
+  String canonicalizePath(String relPath) {
+    relPath = posix.normalize(relPath);
+    String childPath = posix.join(path, relPath);
+    childPath = posix.normalize(childPath);
+    return childPath;
+  }
 }
 
 
@@ -397,8 +413,7 @@ class _PhysicalFolder extends _PhysicalResource implements Folder {
 
   @override
   Resource getChild(String relPath) {
-    String childPath = join(_entry.absolute.path, relPath);
-    return PhysicalResourceProvider.INSTANCE.getResource(childPath);
+    return PhysicalResourceProvider.INSTANCE.getResource(canonicalizePath(relPath));
   }
 
   @override
@@ -420,6 +435,11 @@ class _PhysicalFolder extends _PhysicalResource implements Folder {
 
   @override
   Stream<WatchEvent> get changes => new DirectoryWatcher(_entry.path).events;
+
+  @override
+  String canonicalizePath(String relPath) {
+    return normalize(join(_entry.absolute.path, relPath));
+  }
 }