[recipe_modules/file] add real file module to engine.

recipe_modules/file/example.disable

+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+from recipe_engine.types import freeze
+
+DEPS = [
+  'depot_tools/infra_paths',
+  'file',
+  'recipe_engine/path',
+  'recipe_engine/raw_io',
+  'recipe_engine/step',
+]
+
+
+TEST_CONTENTS = freeze({
+  'simple': 'abcde',
+  'spaces': 'abcde fgh',
+  'symbols': '! ~&&',
+  'multiline': '''ab
+cd
+efg
+''',
+})
+
+
+def RunSteps(api):
+  # listdir demo.
+  result = api.file.listdir('fake dir', '/fake/dir')
+  for element in result:
+    api.step('manipulate %s' % str(element), ['some', 'command'])
+
+  result = api.file.listdir('other', '/faker/dir')
+  for element in result:
+    api.step('manipulate %s' % str(element), ['some', 'command'])
+
+  # mkdtemp demo.
+  for prefix in ('prefix_a', 'prefix_b'):
+    # Create temp dir.
+    temp_dir = api.path.mkdtemp(prefix)
+    assert api.path.exists(temp_dir)
+    # Make |temp_dir| surface in expectation files.
+    api.step('print %s' % prefix, ['echo', temp_dir])
+
+  # move demo
+  api.file.move(
+      'move',
+      api.path['start_dir'].join('source'),
+      api.path['start_dir'].join('destination'))
+
+  # remove demo
+  api.file.remove('remove', api.path['start_dir'].join('some_file'))
+
+  # rmcontents demo
+  api.file.rmcontents('rmcontents', api.path['start_dir'].join('some_dir'))
+
+  # rmwildcard demo
+  api.file.rmwildcard('*.o', api.path['start_dir'])
+
+  for name, content in TEST_CONTENTS.iteritems():
+    api.file.write('write_%s' % name, 'tmp_file.txt', content)
+    actual_content = api.file.read(
+        'read_%s' % name, 'tmp_file.txt',
+        test_data=content
+    )
+    msg = 'expected %s but got %s' % (content, actual_content)
+    assert actual_content == content, msg
+
+  try:
+    # copytree
+    content = 'some file content'
+    tmp_dir = api.path['start_dir'].join('copytree_example_tmp')
+    api.file.makedirs('makedirs', tmp_dir)
+    path = tmp_dir.join('dummy_file')
+    api.file.write('write %s' % path, path, content)
+    new_tmp = api.path['start_dir'].join('copytree_example_tmp2')
+    new_path = new_tmp.join('dummy_file')
+    api.file.copytree('copytree', tmp_dir, new_tmp)
+    actual_content = api.file.read('read %s' % new_path, new_path,
+                                   test_data=content)
+    assert actual_content == content
+
+    # glob.
+    files = api.file.glob(
+        'glob', tmp_dir.join('*'),
+        test_data=[tmp_dir.join('dummy_file')])
+    assert files == [tmp_dir.join('dummy_file')], files
+
+  finally:
+    api.file.rmtree('cleanup', tmp_dir)
+    api.file.rmtree('cleanup2', new_tmp)
+
+
+def GenTests(api):
+  yield api.test('file_io') + api.file.listdir('other', ['aaa'])
+