--- a/tests/mockutil.py	Sat May 30 15:41:52 2015 -0700
+++ b/tests/mockutil.py	Fri Jun 12 17:09:19 2015 -0700
@@ -1,23 +1,10 @@
-import io
-import time
-import errno
-import random
-import codecs
-import shutil
 import os.path
 import mock
-import yaml
 from piecrust.app import PieCrust, PieCrustConfiguration
 from piecrust.page import Page
 from piecrust.rendering import QualifiedPage, PageRenderingContext, render_page
 
 
-resources_path = os.path.abspath(
-            os.path.join(
-            os.path.dirname(__file__),
-            '..', 'piecrust', 'resources'))
-
-
 def get_mock_app(config=None):
     app = mock.MagicMock(spec=PieCrust)
     app.config = PieCrustConfiguration()
@@ -37,376 +24,7 @@
     return rp.content
 
 
-class _MockFsEntry(object):
-    def __init__(self, contents):
-        self.contents = contents
-        self.metadata = {'mtime': time.time()}
-
-
-class _MockFsEntryWriter(object):
-    def __init__(self, entry, mode='rt'):
-        self._entry = entry
-        self._mode = mode
-
-        if 'b' in mode:
-            data = entry.contents
-            if isinstance(data, str):
-                data = data.encode('utf8')
-            self._stream = io.BytesIO(data)
-        else:
-            self._stream = io.StringIO(entry.contents)
-
-    def __getattr__(self, name):
-        return getattr(self._stream, name)
-
-    def __enter__(self):
-        return self
-
-    def __exit__(self, exc_type, exc_value, exc_tb):
-        if 'w' in self._mode:
-            if 'a' in self._mode:
-                self._entry.contents += self._stream.getvalue()
-            else:
-                self._entry.contents = self._stream.getvalue()
-            self._entry.metadata['mtime'] = time.time()
-        self._stream.close()
-
-
-class mock_fs(object):
-    def __init__(self, default_spec=True):
-        self._root = 'root_%d' % random.randrange(1000)
-        self._fs = {self._root: {}}
-        if default_spec:
-            self.withDir('counter')
-            self.withFile('kitchen/config.yml',
-                    "site:\n  title: Mock Website\n")
-
-    def path(self, p):
-        p = p.replace('\\', '/')
-        if p in ['/', '', None]:
-            return '/%s' % self._root
-        return '/%s/%s' % (self._root, p.lstrip('/'))
-
-    def getApp(self, cache=True):
-        root_dir = self.path('/kitchen')
-        return PieCrust(root_dir, cache=cache, debug=True)
-
-    def withDir(self, path):
-        path = path.replace('\\', '/')
-        path = path.lstrip('/')
-        path = '/%s/%s' % (self._root, path)
-        self._createDir(path)
-        return self
-
-    def withFile(self, path, contents):
-        path = path.replace('\\', '/')
-        path = path.lstrip('/')
-        path = '/%s/%s' % (self._root, path)
-        self._createFile(path, contents)
-        return self
-
-    def withAsset(self, path, contents):
-        return self.withFile('kitchen/' + path, contents)
-
-    def withAssetDir(self, path):
-        return self.withDir('kitchen/' + path)
-
-    def withConfig(self, config):
-        return self.withFile(
-                'kitchen/config.yml',
-                yaml.dump(config))
-
-    def withThemeConfig(self, config):
-        return self.withFile(
-                'kitchen/theme/theme_config.yml',
-                yaml.dump(config))
-
-    def withPage(self, url, config=None, contents=None):
-        config = config or {}
-        contents = contents or "A test page."
-        text = "---\n"
-        text += yaml.dump(config)
-        text += "---\n"
-        text += contents
-
-        name, ext = os.path.splitext(url)
-        if not ext:
-            url += '.md'
-        url = url.lstrip('/')
-        return self.withAsset(url, text)
-
-    def withPageAsset(self, page_url, name, contents=None):
-        contents = contents or "A test asset."
-        url_base, ext = os.path.splitext(page_url)
-        dirname = url_base + '-assets'
-        return self.withAsset('%s/%s' % (dirname, name),
-                contents)
-
-    def withPages(self, num, url_factory, config_factory=None,
-                  contents_factory=None):
-        for i in range(num):
-            if isinstance(url_factory, str):
-                url = url_factory.format(idx=i, idx1=(i + 1))
-            else:
-                url = url_factory(i)
-
-            config = None
-            if config_factory:
-                config = config_factory(i)
-
-            contents = None
-            if contents_factory:
-                contents = contents_factory(i)
-
-            self.withPage(url, config, contents)
-        return self
-
-    def getStructure(self, path=None):
-        root = self._fs[self._root]
-        if path:
-            root = self._getEntry(self.path(path))
-            if root is None:
-                raise Exception("No such path: %s" % path)
-            if not isinstance(root, dict):
-                raise Exception("Path is not a directory: %s" % path)
-
-        res = {}
-        for k, v in root.items():
-            self._getStructureRecursive(v, res, k)
-        return res
-
-    def getFileEntry(self, path):
-        entry = self._getEntry(self.path(path))
-        if entry is None:
-            raise Exception("No such file: %s" % path)
-        if not isinstance(entry, _MockFsEntry):
-            raise Exception("Path is not a file: %s" % path)
-        return entry.contents
-
-    def _getStructureRecursive(self, src, target, name):
-        if isinstance(src, _MockFsEntry):
-            target[name] = src.contents
-            return
-
-        e = {}
-        for k, v in src.items():
-            self._getStructureRecursive(v, e, k)
-        target[name] = e
-
-    def _getEntry(self, path):
-        cur = self._fs
-        path = path.replace('\\', '/').lstrip('/')
-        bits = path.split('/')
-        for p in bits:
-            try:
-                cur = cur[p]
-            except KeyError:
-                return None
-        return cur
-
-    def _createDir(self, path):
-        cur = self._fs
-        path = path.replace('\\', '/').strip('/')
-        bits = path.split('/')
-        for b in bits:
-            if b not in cur:
-                cur[b] = {}
-            cur = cur[b]
-        return self
+from .tmpfs import (
+        TempDirFileSystem as mock_fs,
+        TempDirScope as mock_fs_scope)
 
-    def _createFile(self, path, contents):
-        cur = self._fs
-        path = path.replace('\\', '/').lstrip('/')
-        bits = path.split('/')
-        for b in bits[:-1]:
-            if b not in cur:
-                cur[b] = {}
-            cur = cur[b]
-        cur[bits[-1]] = _MockFsEntry(contents)
-        return self
-
-    def _deleteEntry(self, path):
-        parent = self._getEntry(os.path.dirname(path))
-        assert parent is not None
-        name = os.path.basename(path)
-        assert name in parent
-        del parent[name]
-
-
-class mock_fs_scope(object):
-    def __init__(self, fs, open_patches=None):
-        self.open_patches = open_patches or []
-        self._fs = fs
-        self._patchers = []
-        self._originals = {}
-
-    @property
-    def root(self):
-        return self._fs._root
-
-    def __enter__(self):
-        self._startMock()
-        return self
-
-    def __exit__(self, type, value, traceback):
-        self._endMock()
-
-    def _startMock(self):
-        # TODO: sadly, there seems to be no way to replace `open` everywhere?
-        modules = self.open_patches + [
-                '__main__',
-                'piecrust.records',
-                'jinja2.utils']
-        for m in modules:
-            self._createMock('%s.open' % m, open, self._open, create=True)
-
-        self._createMock('codecs.open', codecs.open, self._codecsOpen)
-        self._createMock('os.listdir', os.listdir, self._listdir)
-        self._createMock('os.makedirs', os.makedirs, self._makedirs)
-        self._createMock('os.remove', os.remove, self._remove)
-        self._createMock('os.rename', os.rename, self._rename)
-        self._createMock('os.path.exists', os.path.exists, self._exists)
-        self._createMock('os.path.isdir', os.path.isdir, self._isdir)
-        self._createMock('os.path.isfile', os.path.isfile, self._isfile)
-        self._createMock('os.path.islink', os.path.islink, self._islink)
-        self._createMock('os.path.getmtime', os.path.getmtime, self._getmtime)
-        self._createMock('shutil.copyfile', shutil.copyfile, self._copyfile)
-        self._createMock('shutil.rmtree', shutil.rmtree, self._rmtree)
-        for p in self._patchers:
-            p.start()
-
-    def _endMock(self):
-        for p in self._patchers:
-            p.stop()
-
-    def _createMock(self, name, orig, func, **kwargs):
-        self._originals[name] = orig
-        self._patchers.append(mock.patch(name, func, **kwargs))
-
-    def _doOpen(self, orig_name, path, mode, *args, **kwargs):
-        path = os.path.normpath(path)
-        if path.startswith(resources_path):
-            return self._originals[orig_name](path, mode, *args, **kwargs)
-
-        if 'r' in mode:
-            e = self._getFsEntry(path)
-        elif 'w' in mode or 'x' in mode or 'a' in mode:
-            e = self._getFsEntry(path)
-            if e is None:
-                contents = ''
-                if 'b' in mode:
-                    contents = bytes()
-                self._fs._createFile(path, contents)
-                e = self._getFsEntry(path)
-                assert e is not None
-            elif 'x' in mode:
-                err = IOError("File '%s' already exists" % path)
-                err.errno = errno.EEXIST
-                raise err
-        else:
-            err = IOError("Unsupported open mode: %s" % mode)
-            err.errno = errno.EINVAL
-            raise err
-
-        if e is None:
-            err = IOError("No such file: %s" % path)
-            err.errno = errno.ENOENT
-            raise err
-        if not isinstance(e, _MockFsEntry):
-            err = IOError("'%s' is not a file %s" % (path, e))
-            err.errno = errno.EISDIR
-            raise err
-
-        return _MockFsEntryWriter(e, mode)
-
-    def _open(self, path, mode, *args, **kwargs):
-        return self._doOpen('__main__.open', path, mode, *args, **kwargs)
-
-    def _codecsOpen(self, path, mode, *args, **kwargs):
-        return self._doOpen('codecs.open', path, mode, *args, **kwargs)
-
-    def _listdir(self, path):
-        path = os.path.normpath(path)
-        if path.startswith(resources_path):
-            return self._originals['os.listdir'](path)
-
-        e = self._getFsEntry(path)
-        if e is None:
-            raise OSError("No such directory: %s" % path)
-        if not isinstance(e, dict):
-            raise OSError("'%s' is not a directory." % path)
-        return list(e.keys())
-
-    def _makedirs(self, path, mode=0o777):
-        if not path.replace('\\', '/').startswith('/' + self.root):
-            raise Exception("Shouldn't create directory: %s" % path)
-        self._fs._createDir(path)
-
-    def _remove(self, path):
-        path = os.path.normpath(path)
-        self._fs._deleteEntry(path)
-
-    def _exists(self, path):
-        path = os.path.normpath(path)
-        if path.startswith(resources_path):
-            return self._originals['os.path.isdir'](path)
-        e = self._getFsEntry(path)
-        return e is not None
-
-    def _isdir(self, path):
-        path = os.path.normpath(path)
-        if path.startswith(resources_path):
-            return self._originals['os.path.isdir'](path)
-        e = self._getFsEntry(path)
-        return e is not None and isinstance(e, dict)
-
-    def _isfile(self, path):
-        path = os.path.normpath(path)
-        if path.startswith(resources_path):
-            return self._originals['os.path.isfile'](path)
-        e = self._getFsEntry(path)
-        return e is not None and isinstance(e, _MockFsEntry)
-
-    def _islink(self, path):
-        path = os.path.normpath(path)
-        if path.startswith(resources_path):
-            return self._originals['os.path.islink'](path)
-        return False
-
-    def _getmtime(self, path):
-        path = os.path.normpath(path)
-        if path.startswith(resources_path):
-            return self._originals['os.path.getmtime'](path)
-        e = self._getFsEntry(path)
-        if e is None:
-            raise OSError("No such file: %s" % path)
-        return e.metadata['mtime']
-
-    def _copyfile(self, src, dst):
-        src = os.path.normpath(src)
-        if src.startswith(resources_path):
-            with self._originals['__main__.open'](src, 'r') as fp:
-                src_text = fp.read()
-        else:
-            e = self._getFsEntry(src)
-            src_text = e.contents
-        if not dst.replace('\\', '/').startswith('/' + self.root):
-            raise Exception("Shouldn't copy to: %s" % dst)
-        self._fs._createFile(dst, src_text)
-
-    def _rename(self, src, dst):
-        src = os.path.normpath(src)
-        if src.startswith(resources_path) or dst.startswith(resources_path):
-            raise Exception("Shouldn't rename files in the resources path.")
-        self._copyfile(src, dst)
-        self._remove(src)
-
-    def _rmtree(self, path):
-        if not path.replace('\\', '/').startswith('/' + self.root):
-            raise Exception("Shouldn't delete trees from: %s" % path)
-        e = self._fs._getEntry(os.path.dirname(path))
-        del e[os.path.basename(path)]
-
-    def _getFsEntry(self, path):
-        return self._fs._getEntry(path)
-