Allow DirectoryDescriptor.load to load a file next to a directory.

pkg/scheduled_test/lib/src/descriptor/directory_descriptor.dart

Index: pkg/scheduled_test/lib/src/descriptor/directory_descriptor.dart
diff --git a/pkg/scheduled_test/lib/src/descriptor/directory_descriptor.dart b/pkg/scheduled_test/lib/src/descriptor/directory_descriptor.dart
index 97f8c92341c5f78a573887bccc5c911d625692b3..d3c3cdd4b14a1a4b99a45d96198d6d5ed13c02ee 100644
--- a/pkg/scheduled_test/lib/src/descriptor/directory_descriptor.dart
+++ b/pkg/scheduled_test/lib/src/descriptor/directory_descriptor.dart
@@ -17,7 +17,7 @@ import '../utils.dart';
 final path.Builder _path = new path.Builder(style: path.Style.posix);
 
 /// A descriptor describing a directory containing multiple files.
-class DirectoryDescriptor extends Descriptor {
+class DirectoryDescriptor extends Descriptor implements LoadableDescriptor {
   /// The entries contained within this directory. This is intentionally
   /// mutable.
   final List<Descriptor> contents;
@@ -67,13 +67,20 @@ class DirectoryDescriptor extends Descriptor {
         throw "Can't load '$pathToLoad' from within '$name'.";

[Bob Nystrom, 2013/06/04 15:45:53]

And this.

       }
 
-      var matchingEntries = contents.where((entry) =>
-          entry.name == split.first).toList();
+      var requiresReadable = split.length == 1;
+      var matchingEntries = contents.where((entry) {
+        return entry.name == split.first && (requiresReadable ?
+            entry is ReadableDescriptor :
+            entry is LoadableDescriptor);

[Bob Nystrom, 2013/06/04 15:45:53]

Is DirectoryDescriptor the only thing that implements LoadableDescriptor? If so,
you could get rid of that interface and check for DirectoryDescriptor
explicitly.

Or, if you expect stuff like TarDescriptor to be "directory-like", leave this
as-is.

[nweiz, 2013/06/04 18:26:45]

I want to support directory-like descriptors that don't necessarily inherit from
DirectoryDescriptor.

+      }).toList();
 
+      var adjective = requiresReadable ? 'readable' : 'loadable';
       if (matchingEntries.length == 0) {
-        throw "Couldn't find an entry named '${split.first}' within '$name'.";
+        throw "Couldn't find a $adjective entry named '${split.first}' within "
+            "'$name'.";
       } else if (matchingEntries.length > 1) {
-        throw "Found multiple entries named '${split.first}' within '$name'.";
+        throw "Found multiple $adjective entries named '${split.first}' within "
+            "'$name'.";
       } else {
         var remainingPath = split.sublist(1);
         if (remainingPath.isEmpty) {
@@ -85,9 +92,6 @@ class DirectoryDescriptor extends Descriptor {
     }));
   }
 
-  Stream<List<int>> read() => errorStream("Can't read the contents of '$name': "
-      "is a directory.");
-
   String describe() {
     if (contents.isEmpty) return name;