Roll Observatory packages and add a roll script

packages/which/test/which_impl_test.dart

Index: packages/which/test/which_impl_test.dart
diff --git a/packages/which/test/which_impl_test.dart b/packages/which/test/which_impl_test.dart
new file mode 100755
index 0000000000000000000000000000000000000000..a5057804696083a63385268046ec0ae1876364d6
--- /dev/null
+++ b/packages/which/test/which_impl_test.dart
@@ -0,0 +1,55 @@
+
+library which.test.which_impl;
+
+import 'dart:async';
+
+import 'package:unittest/unittest.dart';
+import 'package:which/src/which_impl.dart';
+
+import 'util.dart';
+
+main() {
+  group('which', () {
+    test('should complete to the first matching executable in candidate paths', () {
+      var candidatePaths = getPosixCandidatePaths('z', '/x/y:/a/b/c', '/foo/bar');
+
+      return which('z', candidatePaths, false, (path, isWindows) => new Future.value(path == '/x/y/z' || path == '/a/b/c/z'), null)
+          .then((path) => expect(path, '/x/y/z'));
+    });
+
+    test('should call orElse if command not found', () {
+      var candidatePaths = getPosixCandidatePaths('z', '/x/y:/a/b/c', '/foo/bar');
+
+      return which('z', candidatePaths, false, (path, isWindows) => new Future.value(false), () => '/or/else')
+          .then((path) => expect(path, '/or/else'));
+    });
+
+    test('should throw state error if command not found and orElse not provided', () {
+      var future = new Future(() =>
+          which('z', [], false, (path, isWindows) => new Future.value(false), null));
+
+      expect(future, throwsStateError);
+    });
+});
+
+  group('whichSync', () {
+    test('should return the first matching executable in candidate paths', () {
+      var candidatePaths = getWindowsCandidatePaths('z', r'C:\x\y;C:\a\b\c', '.EXE;.BAT', r'C:\foo\bar');
+
+      var result = whichSync('find', candidatePaths, true, (path, isWindows) => path == r'C:\x\y\z.BAT' || path == r'C:\a\b\c\z.BAT', null);
+
+      expect(result, r'C:\x\y\z.BAT');
+    });
+
+    test('should call orElse if command not found', () {
+      var candidatePaths = getWindowsCandidatePaths('z', r'C:\x\y;C:\a\b\c', '.EXE;.BAT', r'C:\foo\bar');
+
+      var result = whichSync('find', candidatePaths, true, (path, isWindows) => false, () => r'C:\or\else');
+
+      expect(result, r'C:\or\else');
+    });
+    test('should throw state error if command not found and orElse not provided', () {
+      expect(() => whichSync('z', [], true, (path, isWindows) => false, null), throwsStateError);
+    });
+  });
+}