Add a filesystem descriptor library to scheduled_test.

pkg/scheduled_test/test/descriptor_test.dart

+// Copyright (c) 2013, 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 descriptor_test;
+
+import 'dart:async';
+import 'dart:io';
+
+import 'package:pathos/path.dart' as path;
+import 'package:scheduled_test/descriptor.dart' as d;
+import 'package:scheduled_test/scheduled_test.dart';
+
+import 'metatest.dart';
+
+String sandbox;
+
+void main() {
+  expectTestsPass('file().create() creates a file', () {
+    test('test', () {
+      scheduleSandbox();
+
+      d.file('name.txt', 'contents').create();
+
+      schedule(() {
+        expect(new File(path.join(sandbox, 'name.txt')).readAsString(),
+            completion(equals('contents')));
+      });
+    });
+  });
+
+  expectTestsPass('file().create() overwrites an existing file', () {
+    test('test', () {
+      scheduleSandbox();
+
+      d.file('name.txt', 'contents1').create();
+
+      d.file('name.txt', 'contents2').create();
+
+      schedule(() {
+        expect(new File(path.join(sandbox, 'name.txt')).readAsString(),
+            completion(equals('contents2')));
+      });
+    });
+  });
+
+  expectTestsPass('file().create() with a RegExp name fails', () {
+    var errors;
+    test('test 1', () {
+      scheduleSandbox();
+
+      currentSchedule.onException.schedule(() {
+        errors = currentSchedule.errors;
+      });
+
+      d.file(new RegExp(r'name\.txt'), 'contents').create();
+    });
+
+    test('test 2', () {
+      expect(errors, everyElement(new isInstanceOf<ScheduleError>()));
+      expect(errors.map((e) => e.error), equals([
+        r"Pattern /name\.txt/ must be a string."
+      ]), verbose: true);
+    });
+  }, passing: ['test 2']);
+
+  expectTestsPass('file().validate() completes successfully if the filesystem '
+      'matches the descriptor', () {
+    test('test', () {
+      scheduleSandbox();
+
+      schedule(() {
+        return new File(path.join(sandbox, 'name.txt'))
+            .writeAsString('contents');
+      });
+
+      d.file('name.txt', 'contents').validate();
+    });
+  });
+
+  expectTestsPass("file().validate() fails if there's a file with the wrong "
+      "contents", () {
+    var errors;
+    test('test 1', () {
+      scheduleSandbox();
+
+      currentSchedule.onException.schedule(() {
+        errors = currentSchedule.errors;
+      });
+
+      schedule(() {
+        return new File(path.join(sandbox, 'name.txt'))
+            .writeAsString('wrongtents');
+      });
+
+      d.file('name.txt', 'contents').validate();
+    });
+
+    test('test 2', () {
+      expect(errors, everyElement(new isInstanceOf<ScheduleError>()));
+      expect(errors.map((e) => e.error), equals([
+        "File 'name.txt' should contain:\n"
+        "| contents\n"
+        "but actually contained:\n"
+        "X wrongtents"
+      ]), verbose: true);
+    });
+  }, passing: ['test 2']);
+
+  expectTestsPass("file().validate() fails if there's no file", () {
+    var errors;
+    test('test 1', () {
+      scheduleSandbox();
+
+      currentSchedule.onException.schedule(() {
+        errors = currentSchedule.errors;
+      });
+
+      d.file('name.txt', 'contents').validate();
+    });
+
+    test('test 2', () {
+      expect(errors, everyElement(new isInstanceOf<ScheduleError>()));
+      expect(errors.length, equals(1));
+      expect(errors.first.error,
+          matches(r"^File not found: '[^']+/name\.txt'\.$"));
+    });
+  }, passing: ['test 2']);
+
+  expectTestsPass('file().validate() with a RegExp completes successfully if '
+      'the filesystem matches the descriptor', () {
+    test('test', () {
+      scheduleSandbox();
+
+      schedule(() {
+        return new File(path.join(sandbox, 'name.txt'))
+            .writeAsString('contents');
+      });
+
+      d.file(new RegExp(r'na..\.txt'), 'contents').validate();
+    });
+  });
+
+  expectTestsPass("file().validate() with a RegExp fails if there's a file "
+      "with the wrong contents", () {
+    var errors;
+    test('test 1', () {
+      scheduleSandbox();
+
+      currentSchedule.onException.schedule(() {
+        errors = currentSchedule.errors;
+      });
+
+      schedule(() {
+        return new File(path.join(sandbox, 'name.txt'))
+            .writeAsString('some\nwrongtents');
+      });
+
+      d.file(new RegExp(r'na..\.txt'), 'some\ncontents\nand stuff').validate();
+    });
+
+    test('test 2', () {
+      expect(errors, everyElement(new isInstanceOf<ScheduleError>()));
+      expect(errors.map((e) => e.error), equals([
+        "File 'name.txt' (matching /na..\\.txt/) should contain:\n"
+        "| some\n"
+        "| contents\n"
+        "| and stuff\n"
+        "but actually contained:\n"
+        "| some\n"
+        "X wrongtents\n"
+        "? and stuff"
+      ]), verbose: true);
+    });
+  }, passing: ['test 2']);
+
+  expectTestsPass("file().validate() with a RegExp fails if there's no "
+      "file", () {
+    var errors;
+    test('test 1', () {
+      scheduleSandbox();
+
+      currentSchedule.onException.schedule(() {
+        errors = currentSchedule.errors;
+      });
+
+      d.file(new RegExp(r'na..\.txt'), 'contents').validate();
+    });
+
+    test('test 2', () {
+      expect(errors, everyElement(new isInstanceOf<ScheduleError>()));
+      expect(errors.length, equals(1));
+      expect(errors.first.error,
+          matches(r"^No entry found in '[^']+' matching /na\.\.\\\.txt/\.$"));
+    });
+  }, passing: ['test 2']);
+
+  expectTestsPass("file().validate() with a RegExp fails if there are multiple "
+      "matching files", () {
+    var errors;
+    test('test 1', () {
+      scheduleSandbox();
+
+      currentSchedule.onException.schedule(() {
+        errors = currentSchedule.errors;
+      });
+
+      schedule(() {
+        return Future.wait([
+          new File(path.join(sandbox, 'name.txt')).writeAsString('contents'),
+          new File(path.join(sandbox, 'nape.txt')).writeAsString('contents'),
+          new File(path.join(sandbox, 'nail.txt')).writeAsString('contents')
+        ]);
+      });
+
+      d.file(new RegExp(r'na..\.txt'), 'contents').validate();
+    });
+
+    test('test 2', () {
+      expect(errors, everyElement(new isInstanceOf<ScheduleError>()));
+      expect(errors.length, equals(1));
+      expect(errors.first.error,
+          matches(
+              r"^Multiple entries found in '[^']+' matching /na\.\.\\\.txt/:\n"
+              r"\* .*/nail\.txt\n"
+              r"\* .*/name\.txt\n"
+              r"\* .*/nape\.txt"));
+    });
+  }, passing: ['test 2']);
+
+  expectTestsPass("file().read() returns the contents of the file as a stream",
+      () {
+    test('test', () {
+      expect(byteStreamToString(d.file('name.txt', 'contents').read()),
+          completion(equals('contents')));
+    });
+  });
+
+  expectTestsPass("file().load() throws an error", () {
+    test('test', () {
+      expect(d.file('name.txt', 'contents').load('path').toList(),
+          throwsA(equals("Can't load 'path' from within 'name.txt': not a "
+                         "directory.")));
+    });
+  });
+
+  expectTestsPass("file().describe() returns the filename", () {
+    test('test', () {
+      expect(d.file('name.txt', 'contents').describe(), equals('name.txt'));
+    });
+  });
+
+  expectTestsPass("file().describe() with a RegExp describes the file", () {
+    test('test', () {
+      expect(d.file(new RegExp(r'na..\.txt'), 'contents').describe(),
+          equals(r'file matching /na..\.txt/'));
+    });
+  });
+
+  expectTestsPass('binaryFile().create() creates a file', () {
+    test('test', () {
+      scheduleSandbox();
+
+      d.binaryFile('name.bin', [1, 2, 3, 4, 5]).create();
+
+      schedule(() {
+        expect(new File(path.join(sandbox, 'name.bin')).readAsBytes(),
+            completion(equals([1, 2, 3, 4, 5])));
+      });
+    });
+  });
+
+  expectTestsPass('binaryFile().validate() completes successfully if the '
+      'filesystem matches the descriptor', () {
+    test('test', () {
+      scheduleSandbox();
+
+      schedule(() {
+        return new File(path.join(sandbox, 'name.bin'))
+            .writeAsBytes([1, 2, 3, 4, 5]);
+      });
+
+      d.binaryFile('name.bin', [1, 2, 3, 4, 5]).validate();
+    });
+  });
+
+  expectTestsPass("binaryFile().validate() fails if there's a file with the "
+      "wrong contents", () {
+    var errors;
+    test('test 1', () {
+      scheduleSandbox();
+
+      currentSchedule.onException.schedule(() {
+        errors = currentSchedule.errors;
+      });
+
+      schedule(() {
+        return new File(path.join(sandbox, 'name.bin'))
+            .writeAsBytes([2, 4, 6, 8, 10]);
+      });
+
+      d.binaryFile('name.bin', [1, 2, 3, 4, 5]).validate();
+    });
+
+    test('test 2', () {
+      expect(errors, everyElement(new isInstanceOf<ScheduleError>()));
+      expect(errors.map((e) => e.error), equals([
+        "File 'name.bin' didn't contain the expected binary data."
+      ]), verbose: true);
+    });
+  }, passing: ['test 2']);
+
+  expectTestsPass("directory().create() creates a directory and its contents",
+      () {
+    test('test', () {
+      scheduleSandbox();
+
+      d.dir('dir', [
+        d.dir('subdir', [
+          d.file('subfile1.txt', 'subcontents1'),
+          d.file('subfile2.txt', 'subcontents2')
+        ]),
+        d.file('file1.txt', 'contents1'),
+        d.file('file2.txt', 'contents2')
+      ]).create();
+
+      schedule(() {
+        expect(new File(path.join(sandbox, 'dir', 'file1.txt')).readAsString(),
+            completion(equals('contents1')));
+        expect(new File(path.join(sandbox, 'dir', 'file2.txt')).readAsString(),
+            completion(equals('contents2')));
+        expect(new File(path.join(sandbox, 'dir', 'subdir', 'subfile1.txt'))
+                .readAsString(),
+            completion(equals('subcontents1')));
+        expect(new File(path.join(sandbox, 'dir', 'subdir', 'subfile2.txt'))
+                .readAsString(),
+            completion(equals('subcontents2')));
+      });
+    });
+  });
+
+  expectTestsPass("directory().create() works if the directory already exists",
+      () {
+    test('test', () {
+      scheduleSandbox();
+
+      d.dir('dir').create();
+      d.dir('dir', [d.file('name.txt', 'contents')]).create();
+
+      schedule(() {
+        expect(new File(path.join(sandbox, 'dir', 'name.txt')).readAsString(),
+            completion(equals('contents')));
+      });
+    });
+  });
+
+  expectTestsPass("directory().create() with a RegExp name fails", () {
+    var errors;
+    test('test 1', () {
+      scheduleSandbox();
+
+      currentSchedule.onException.schedule(() {
+        errors = currentSchedule.errors;
+      });
+
+      d.dir(new RegExp('dir')).create();
+    });
+
+    test('test 2', () {
+      expect(errors, everyElement(new isInstanceOf<ScheduleError>()));
+      expect(errors.map((e) => e.error), equals([
+        "Pattern /dir/ must be a string."
+      ]), verbose: true);
+    });
+  }, passing: ['test 2']);
+
+  expectTestsPass("directory().validate() completes successfully if the "
+      "filesystem matches the descriptor", () {
+    test('test', () {
+      scheduleSandbox();
+
+      schedule(() {
+        var dirPath = path.join(sandbox, 'dir');
+        var subdirPath = path.join(dirPath, 'subdir');
+        return new Directory(subdirPath).create(recursive: true).then((_) {
+          return Future.wait([
+            new File(path.join(dirPath, 'file1.txt'))
+                .writeAsString('contents1'),
+            new File(path.join(dirPath, 'file2.txt'))
+                .writeAsString('contents2'),
+            new File(path.join(subdirPath, 'subfile1.txt'))
+                .writeAsString('subcontents1'),
+            new File(path.join(subdirPath, 'subfile2.txt'))
+                .writeAsString('subcontents2')
+          ]);
+        });
+      });
+
+      d.dir('dir', [
+        d.dir('subdir', [
+          d.file('subfile1.txt', 'subcontents1'),
+          d.file('subfile2.txt', 'subcontents2')
+        ]),
+        d.file('file1.txt', 'contents1'),
+        d.file('file2.txt', 'contents2')
+      ]).validate();
+    });
+  });
+
+  expectTestsPass("directory().validate() fails if a directory isn't found"
+      , () {
+    var errors;
+    test('test 1', () {
+      scheduleSandbox();
+
+      currentSchedule.onException.schedule(() {
+        errors = currentSchedule.errors;
+      });
+
+      schedule(() {
+        var dirPath = path.join(sandbox, 'dir');
+        return new Directory(dirPath).create().then((_) {
+          return Future.wait([
+            new File(path.join(dirPath, 'file1.txt'))
+                .writeAsString('contents1'),
+            new File(path.join(dirPath, 'file2.txt'))
+                .writeAsString('contents2')
+          ]);
+        });
+      });
+
+      d.dir('dir', [
+        d.dir('subdir', [
+          d.file('subfile1.txt', 'subcontents1'),
+          d.file('subfile2.txt', 'subcontents2')
+        ]),
+        d.file('file1.txt', 'contents1'),
+        d.file('file2.txt', 'contents2')
+      ]).validate();
+    });
+
+    test('test 2', () {
+      expect(errors, everyElement(new isInstanceOf<ScheduleError>()));
+      expect(errors.length, equals(1));
+      expect(errors.first.error,
+          matches(r"^Directory not found: '[^']+/dir/subdir'\.$"));
+    });
+  }, passing: ['test 2']);
+
+  expectTestsPass("directory().validate() fails if a file isn't found", () {
+    var errors;
+    test('test 1', () {
+      scheduleSandbox();
+
+      currentSchedule.onException.schedule(() {
+        errors = currentSchedule.errors;
+      });
+
+      schedule(() {
+        var dirPath = path.join(sandbox, 'dir');
+        var subdirPath = path.join(dirPath, 'subdir');
+        return new Directory(subdirPath).create(recursive: true).then((_) {
+          return Future.wait([
+            new File(path.join(dirPath, 'file1.txt'))
+                .writeAsString('contents1'),
+            new File(path.join(subdirPath, 'subfile1.txt'))
+                .writeAsString('subcontents1'),
+            new File(path.join(subdirPath, 'subfile2.txt'))
+                .writeAsString('subcontents2')
+          ]);
+        });
+      });
+
+      d.dir('dir', [
+        d.dir('subdir', [
+          d.file('subfile1.txt', 'subcontents1'),
+          d.file('subfile2.txt', 'subcontents2')
+        ]),
+        d.file('file1.txt', 'contents1'),
+        d.file('file2.txt', 'contents2')
+      ]).validate();
+    });
+
+    test('test 2', () {
+      expect(errors, everyElement(new isInstanceOf<ScheduleError>()));
+      expect(errors.length, equals(1));
+      expect(errors.first.error,
+          matches(r"^File not found: '[^']+/dir/file2\.txt'\.$"));
+    });
+  }, passing: ['test 2']);
+
+  expectTestsPass("directory().validate() fails if a file has the wrong "
+      "contents", () {
+    var errors;
+    test('test 1', () {
+      scheduleSandbox();
+
+      currentSchedule.onException.schedule(() {
+        errors = currentSchedule.errors;
+      });
+
+      schedule(() {
+        var dirPath = path.join(sandbox, 'dir');
+        var subdirPath = path.join(dirPath, 'subdir');
+        return new Directory(subdirPath).create(recursive: true).then((_) {
+          return Future.wait([
+            new File(path.join(dirPath, 'file1.txt'))
+                .writeAsString('contents1'),
+            new File(path.join(dirPath, 'file2.txt'))
+                .writeAsString('contents2'),
+            new File(path.join(subdirPath, 'subfile1.txt'))
+                .writeAsString('wrongtents1'),
+            new File(path.join(subdirPath, 'subfile2.txt'))
+                .writeAsString('subcontents2')
+          ]);
+        });
+      });
+
+      d.dir('dir', [
+        d.dir('subdir', [
+          d.file('subfile1.txt', 'subcontents1'),
+          d.file('subfile2.txt', 'subcontents2')
+        ]),
+        d.file('file1.txt', 'contents1'),
+        d.file('file2.txt', 'contents2')
+      ]).validate();
+    });
+
+    test('test 2', () {
+      expect(errors, everyElement(new isInstanceOf<ScheduleError>()));
+      expect(errors.map((e) => e.error), equals([
+        "File 'subfile1.txt' should contain:\n"
+        "| subcontents1\n"
+        "but actually contained:\n"
+        "X wrongtents1"
+      ]));
+    });
+  }, passing: ['test 2']);
+
+  expectTestsPass("directory().validate() with a RegExp completes successfully "
+      "if the filesystem matches the descriptor", () {
+    test('test', () {
+      scheduleSandbox();
+
+      schedule(() {
+        var dirPath = path.join(sandbox, 'dir');
+        var subdirPath = path.join(dirPath, 'subdir');
+        return new Directory(subdirPath).create(recursive: true).then((_) {
+          return Future.wait([
+            new File(path.join(dirPath, 'file1.txt'))
+                .writeAsString('contents1'),
+            new File(path.join(dirPath, 'file2.txt'))
+                .writeAsString('contents2'),
+            new File(path.join(subdirPath, 'subfile1.txt'))
+                .writeAsString('subcontents1'),
+            new File(path.join(subdirPath, 'subfile2.txt'))
+                .writeAsString('subcontents2')
+          ]);
+        });
+      });
+
+      d.dir(new RegExp('d.r'), [
+        d.dir('subdir', [
+          d.file('subfile1.txt', 'subcontents1'),
+          d.file('subfile2.txt', 'subcontents2')
+        ]),
+        d.file('file1.txt', 'contents1'),
+        d.file('file2.txt', 'contents2')
+      ]).validate();
+    });
+  });
+
+  expectTestsPass("directory().validate() with a RegExp fails if there's a dir "
+      "with the wrong contents", () {
+    var errors;
+    test('test 1', () {
+      scheduleSandbox();
+
+      currentSchedule.onException.schedule(() {
+        errors = currentSchedule.errors;
+      });
+
+      schedule(() {
+        var dirPath = path.join(sandbox, 'dir');
+        var subdirPath = path.join(dirPath, 'subdir');
+        return new Directory(subdirPath).create(recursive: true).then((_) {
+          return Future.wait([
+            new File(path.join(dirPath, 'file1.txt'))
+                .writeAsString('contents1'),
+            new File(path.join(subdirPath, 'subfile1.txt'))
+                .writeAsString('subcontents1'),
+            new File(path.join(subdirPath, 'subfile2.txt'))
+                .writeAsString('subcontents2')
+          ]);
+        });
+      });
+
+      d.dir(new RegExp('d.r'), [
+        d.dir('subdir', [
+          d.file('subfile1.txt', 'subcontents1'),
+          d.file('subfile2.txt', 'subcontents2')
+        ]),
+        d.file('file1.txt', 'contents1'),
+        d.file('file2.txt', 'contents2')
+      ]).validate();
+    });
+
+    test('test 2', () {
+      expect(errors, everyElement(new isInstanceOf<ScheduleError>()));
+      expect(errors.length, equals(1));
+      expect(errors.first.error,
+          matches(r"^File not found: '[^']+/dir/file2\.txt'\.$"));
+    });
+  }, passing: ['test 2']);
+
+  expectTestsPass("directory().validate() with a RegExp fails if there's no "
+      "dir", () {
+    var errors;
+    test('test 1', () {
+      scheduleSandbox();
+
+      currentSchedule.onException.schedule(() {
+        errors = currentSchedule.errors;
+      });
+
+      d.dir(new RegExp('d.r'), [
+        d.dir('subdir', [
+          d.file('subfile1.txt', 'subcontents1'),
+          d.file('subfile2.txt', 'subcontents2')
+        ]),
+        d.file('file1.txt', 'contents1'),
+        d.file('file2.txt', 'contents2')
+      ]).validate();
+    });
+
+    test('test 2', () {
+      expect(errors, everyElement(new isInstanceOf<ScheduleError>()));
+      expect(errors.length, equals(1));
+      expect(errors.first.error,
+          matches(r"^No entry found in '[^']+' matching /d\.r/\.$"));
+    });
+  }, passing: ['test 2']);
+
+  expectTestsPass("directory().validate() with a RegExp fails if there are "
+      "multiple matching dirs", () {
+    var errors;
+    test('test 1', () {
+      scheduleSandbox();
+
+      currentSchedule.onException.schedule(() {
+        errors = currentSchedule.errors;
+      });
+
+      schedule(() {
+        return Future.wait(['dir', 'dar', 'dor'].map((dir) {
+          var dirPath = path.join(sandbox, dir);
+          var subdirPath = path.join(dirPath, 'subdir');
+          return new Directory(subdirPath).create(recursive: true).then((_) {
+            return Future.wait([
+              new File(path.join(dirPath, 'file1.txt'))
+                  .writeAsString('contents1'),
+              new File(path.join(dirPath, 'file2.txt'))
+                  .writeAsString('contents2'),
+              new File(path.join(subdirPath, 'subfile1.txt'))
+                  .writeAsString('subcontents1'),
+              new File(path.join(subdirPath, 'subfile2.txt'))
+                  .writeAsString('subcontents2')
+            ]);
+          });
+        }));
+      });
+
+      d.dir(new RegExp('d.r'), [
+        d.dir('subdir', [
+          d.file('subfile1.txt', 'subcontents1'),
+          d.file('subfile2.txt', 'subcontents2')
+        ]),
+        d.file('file1.txt', 'contents1'),
+        d.file('file2.txt', 'contents2')
+      ]).validate();
+    });
+
+    test('test 2', () {
+      expect(errors, everyElement(new isInstanceOf<ScheduleError>()));
+      expect(errors.length, equals(1));
+      expect(errors.first.error,
+          matches(
+              r"^Multiple entries found in '[^']+' matching /d\.r/:\n"
+              r"\* .*/dar\n"
+              r"\* .*/dir\n"
+              r"\* .*/dor"));
+    });
+  }, passing: ['test 2']);
+
+  expectTestsPass("directory().load() loads a file", () {
+    test('test', () {
+      var dir = d.dir('dir', [d.file('name.txt', 'contents')]);
+      expect(byteStreamToString(dir.load('name.txt')),
+          completion(equals('contents')));
+    });
+  });
+
+  expectTestsPass("directory().load() loads a deeply-nested file", () {
+    test('test', () {
+      var dir = d.dir('dir', [
+        d.dir('subdir', [
+          d.file('name.txt', 'subcontents')
+        ]),
+        d.file('name.txt', 'contents')
+      ]);
+
+      expect(byteStreamToString(dir.load(path.join('subdir', 'name.txt'))),
+          completion(equals('subcontents')));
+    });
+  });
+
+  expectTestsPass("directory().read() fails", () {
+    test('test', () {
+      var dir = d.dir('dir', [d.file('name.txt', 'contents')]);
+      expect(dir.read().toList(),
+          throwsA(equals("Can't read the contents of 'dir': is a directory.")));
+    });
+  });
+
+  expectTestsPass("directory().load() fails to load a nested directory", () {
+    test('test', () {
+      var dir = d.dir('dir', [
+        d.dir('subdir', [
+          d.file('name.txt', 'subcontents')
+        ]),
+        d.file('name.txt', 'contents')
+      ]);
+
+      expect(dir.load('subdir').toList(),
+          throwsA(equals("Can't load the contents of 'subdir': is a "
+              "directory.")));
+    });
+  });
+
+  expectTestsPass("directory().load() fails to load an absolute path", () {
+    test('test', () {
+      var dir = d.dir('dir', [d.file('name.txt', 'contents')]);
+
+      expect(dir.load('/name.txt').toList(),
+          throwsA(equals("Can't load absolute path '/name.txt'.")));
+    });
+  });
+
+  expectTestsPass("directory().load() fails to load '.', '..', or ''", () {
+    test('test', () {
+      var dir = d.dir('dir', [d.file('name.txt', 'contents')]);
+
+      expect(dir.load('.').toList(),
+          throwsA(equals("Can't load '.' from within 'dir'.")));
+
+      expect(dir.load('..').toList(),
+          throwsA(equals("Can't load '..' from within 'dir'.")));
+
+      expect(dir.load('').toList(),
+          throwsA(equals("Can't load '' from within 'dir'.")));
+    });
+  });
+
+  expectTestsPass("directory().load() fails to load a file with a RegExp name",
+      () {
+    test('test', () {
+      var dir = d.dir('dir', [d.file(new RegExp(r'name\.txt'), 'contents')]);
+
+      expect(dir.load('name.txt').toList(),
+          throwsA(equals(r"Pattern /name\.txt/ must be a string.")));
+    });
+  });
+
+  expectTestsPass("directory().load() fails to load a file that doesn't exist",
+      () {
+    test('test', () {
+      var dir = d.dir('dir', [d.file('name.txt', 'contents')]);
+
+      expect(dir.load('not-name.txt').toList(),
+          throwsA(equals("Couldn't find an entry named 'not-name.txt' within "
+              "'dir'.")));
+    });
+  });
+
+  expectTestsPass("directory().load() fails to load a file that exists "
+      "multiple times", () {
+    test('test', () {
+      var dir = d.dir('dir', [
+        d.file('name.txt', 'contents'),
+        d.file('name.txt', 'contents')
+      ]);
+
+      expect(dir.load('name.txt').toList(),
+          throwsA(equals("Found multiple entries named 'name.txt' within "
+              "'dir'.")));
+    });
+  });
+
+  expectTestsPass("directory().describe() lists the contents of the directory",
+      () {
+    test('test', () {
+      var dir = d.dir('dir', [
+        d.file('file1.txt', 'contents1'),
+        d.file('file2.txt', 'contents2'),
+        d.file(new RegExp(r're\.txt'), 're-contents')
+      ]);
+
+      expect(dir.describe(), equals(
+          "dir\n"
+          "|-- file1.txt\n"
+          "|-- file2.txt\n"
+          "'-- file matching /re\\.txt/"));
+    });
+  });
+
+  expectTestsPass("directory().describe() lists the contents of nested "
+      "directories", () {
+    test('test', () {
+      var dir = d.dir('dir', [
+        d.file('file1.txt', 'contents1'),
+        d.dir('subdir', [
+          d.file('subfile1.txt', 'subcontents1'),
+          d.file('subfile2.txt', 'subcontents2'),
+          d.dir('subsubdir', [
+            d.file('subsubfile.txt', 'subsubcontents')
+          ])
+        ]),
+        d.file('file2.txt', 'contents2')
+      ]);
+
+      expect(dir.describe(), equals(
+          "dir\n"
+          "|-- file1.txt\n"
+          "|-- subdir\n"
+          "|   |-- subfile1.txt\n"
+          "|   |-- subfile2.txt\n"
+          "|   '-- subsubdir\n"
+          "|       '-- subsubfile.txt\n"
+          "'-- file2.txt"));
+    });
+  });
+
+  expectTestsPass("directory().describe() with a RegExp describes the "
+      "directory", () {
+    test('test', () {
+      var dir = d.dir(new RegExp(r'd.r'), [
+        d.file('file1.txt', 'contents1'),
+        d.file('file2.txt', 'contents2')
+      ]);
+
+      expect(dir.describe(), equals(
+          "directory matching /d.r/\n"
+          "|-- file1.txt\n"
+          "'-- file2.txt"));
+    });
+  });
+
+  expectTestsPass("directory().describe() with no contents returns the "
+      "directory name", () {
+    test('test', () {
+      expect(d.dir('dir').describe(), equals('dir'));
+    });
+  });
+}
+
+void scheduleSandbox() {
+  schedule(() {
+    return new Directory('').createTemp().then((dir) {
+      sandbox = dir.path;
+      d.defaultRoot = sandbox;
+    });
+  });
+
+  currentSchedule.onComplete.schedule(() {
+    d.defaultRoot = null;
+    if (sandbox == null) return;
+    var oldSandbox = sandbox;
+    sandbox = null;
+    return new Directory(oldSandbox).delete(recursive: true);
+  });
+}
+
+Future<List<int>> byteStreamToList(Stream<List<int>> stream) {
+  return stream.reduce(<int>[], (buffer, chunk) {
+    buffer.addAll(chunk);
+    return buffer;
+  });
+}
+
+Future<String> byteStreamToString(Stream<List<int>> stream) =>
+  byteStreamToList(stream).then((bytes) => new String.fromCharCodes(bytes));