Extract functions from path recipe module so that step can depend on it

scripts/slave/recipe_modules/file/api.py

Index: scripts/slave/recipe_modules/file/api.py
diff --git a/scripts/slave/recipe_modules/file/api.py b/scripts/slave/recipe_modules/file/api.py
index 56482112c9a99a5734ae68e5c9e7ff708dd0d7b6..11135feda78857195df51f39da977b465bdf1a53 100644
--- a/scripts/slave/recipe_modules/file/api.py
+++ b/scripts/slave/recipe_modules/file/api.py
@@ -98,3 +98,94 @@ class FileApi(recipe_api.RecipeApi):
         **kwargs
     )
 
+  def listdir(self, name, path, step_test_data=None):
+    """Wrapper for os.listdir."""
+    return self.m.python.inline('listdir %s' % name,
+      """
+      import json, os, sys
+      if os.path.exists(sys.argv[1]) and os.path.isdir(sys.argv[1]):
+        with open(sys.argv[2], 'w') as f:
+          json.dump(os.listdir(sys.argv[1]), f)
+      """,
+      args=[path, self.m.json.output()],
+      step_test_data=(step_test_data or
+                      self.test_api.listdir(['file 1', 'file 2'])),
+    ).json.output
+
+  def makedirs(self, name, path, mode=0777):
+    """
+    Like os.makedirs, except that if the directory exists, then there is no
+    error.
+    """
+    self.m.path.assert_absolute(path)
+    self.m.python.inline(
+      'makedirs ' + name,
+      """
+      import sys, os
+      path = sys.argv[1]
+      mode = int(sys.argv[2])
+      if not os.path.isdir(path):
+        if os.path.exists(path):
+          print "%s exists but is not a dir" % path
+          sys.exit(1)
+        os.makedirs(path, mode)
+      """,
+      args=[path, str(mode)],
+    )
+    self.m.path.mock_add_paths(path)
+
+  def rmtree(self, name, path):
+    """Wrapper for chromium_utils.RemoveDirectory."""
+    self.m.path.assert_absolute(path)
+    self.m.python.inline(
+      'rmtree ' + name,
+      """
+      import os, sys
+      from common import chromium_utils
+
+      if os.path.exists(sys.argv[1]):
+        chromium_utils.RemoveDirectory(sys.argv[1])
+      """,
+      args=[path],
+    )
+
+  def rmcontents(self, name, path):
+    """
+    Similar to rmtree, but removes only contents not the directory.
+
+    This is useful e.g. when removing contents of current working directory.
+    Deleting current working directory makes all further getcwd calls fail
+    until chdir is called. chdir would be tricky in recipes, so we provide
+    a call that doesn't delete the directory itself.
+    """
+    self.m.path.assert_absolute(path)
+    self.m.python.inline(
+      'rmcontents ' + name,
+      """
+      import os, sys
+      from common import chromium_utils
+
+      for p in [os.path.join(sys.argv[1], x) for x in os.listdir(sys.argv[1])]:
+        if os.path.isdir(p):
+          chromium_utils.RemoveDirectory(p)
+        else:
+          os.unlink(p)
+      """,
+      args=[path],
+    )
+
+  def rmwildcard(self, pattern, path, **kwargs):
+    """
+    Removes all files in the subtree of path matching the glob pattern.
+    """
+    self.m.path.assert_absolute(path)
+    self.m.python.inline(
+      'rmwildcard %s in %s' % (pattern, path),
+      """
+      import sys
+      from common import chromium_utils
+
+      chromium_utils.RemoveFilesWildcards(sys.argv[1], root=sys.argv[2])
+      """,
+      args=[pattern,path],
+      **kwargs)