Example of refactoring using rope library.

tools/telemetry/third_party/rope/rope/base/fscommands.py

Index: tools/telemetry/third_party/rope/rope/base/fscommands.py
diff --git a/tools/telemetry/third_party/rope/rope/base/fscommands.py b/tools/telemetry/third_party/rope/rope/base/fscommands.py
new file mode 100644
index 0000000000000000000000000000000000000000..8c51e6072ed5f808c7ce6704321d5ce84d0e6047
--- /dev/null
+++ b/tools/telemetry/third_party/rope/rope/base/fscommands.py
@@ -0,0 +1,283 @@
+"""Project file system commands.
+
+This modules implements file system operations used by rope.  Different
+version control systems can be supported by implementing the interface
+provided by `FileSystemCommands` class.  See `SubversionCommands` and
+`MercurialCommands` for example.
+
+"""
+import os
+import shutil
+import subprocess
+
+try:
+    unicode
+except NameError:
+    unicode = str
+
+def create_fscommands(root):
+    dirlist = os.listdir(root)
+    commands = {'.hg': MercurialCommands,
+                '.svn': SubversionCommands,
+                '.git': GITCommands,
+                '_svn': SubversionCommands,
+                '_darcs': DarcsCommands}
+    for key in commands:
+        if key in dirlist:
+            try:
+                return commands[key](root)
+            except (ImportError, OSError):
+                pass
+    return FileSystemCommands()
+
+
+class FileSystemCommands(object):
+
+    def create_file(self, path):
+        open(path, 'w').close()
+
+    def create_folder(self, path):
+        os.mkdir(path)
+
+    def move(self, path, new_location):
+        shutil.move(path, new_location)
+
+    def remove(self, path):
+        if os.path.isfile(path):
+            os.remove(path)
+        else:
+            shutil.rmtree(path)
+
+    def write(self, path, data):
+        file_ = open(path, 'wb')
+        try:
+            file_.write(data)
+        finally:
+            file_.close()
+
+
+class SubversionCommands(object):
+
+    def __init__(self, *args):
+        self.normal_actions = FileSystemCommands()
+        import pysvn
+        self.client = pysvn.Client()
+
+    def create_file(self, path):
+        self.normal_actions.create_file(path)
+        self.client.add(path, force=True)
+
+    def create_folder(self, path):
+        self.normal_actions.create_folder(path)
+        self.client.add(path, force=True)
+
+    def move(self, path, new_location):
+        self.client.move(path, new_location, force=True)
+
+    def remove(self, path):
+        self.client.remove(path, force=True)
+
+    def write(self, path, data):
+        self.normal_actions.write(path, data)
+
+
+class MercurialCommands(object):
+
+    def __init__(self, root):
+        self.hg = self._import_mercurial()
+        self.normal_actions = FileSystemCommands()
+        try:
+            self.ui = self.hg.ui.ui(
+                verbose=False, debug=False, quiet=True,
+                interactive=False, traceback=False, report_untrusted=False)
+        except:
+            self.ui = self.hg.ui.ui()
+            self.ui.setconfig('ui', 'interactive', 'no')
+            self.ui.setconfig('ui', 'debug', 'no')
+            self.ui.setconfig('ui', 'traceback', 'no')
+            self.ui.setconfig('ui', 'verbose', 'no')
+            self.ui.setconfig('ui', 'report_untrusted', 'no')
+            self.ui.setconfig('ui', 'quiet', 'yes')
+
+        self.repo = self.hg.hg.repository(self.ui, root)
+
+    def _import_mercurial(self):
+        import mercurial.commands
+        import mercurial.hg
+        import mercurial.ui
+        return mercurial
+
+    def create_file(self, path):
+        self.normal_actions.create_file(path)
+        self.hg.commands.add(self.ui, self.repo, path)
+
+    def create_folder(self, path):
+        self.normal_actions.create_folder(path)
+
+    def move(self, path, new_location):
+        self.hg.commands.rename(self.ui, self.repo, path,
+                                new_location, after=False)
+
+    def remove(self, path):
+        self.hg.commands.remove(self.ui, self.repo, path)
+
+    def write(self, path, data):
+        self.normal_actions.write(path, data)
+
+
+class GITCommands(object):
+
+    def __init__(self, root):
+        self.root = root
+        self._do(['version'])
+        self.normal_actions = FileSystemCommands()
+
+    def create_file(self, path):
+        self.normal_actions.create_file(path)
+        self._do(['add', self._in_dir(path)])
+
+    def create_folder(self, path):
+        self.normal_actions.create_folder(path)
+
+    def move(self, path, new_location):
+        self._do(['mv', self._in_dir(path), self._in_dir(new_location)])
+
+    def remove(self, path):
+        self._do(['rm', self._in_dir(path)])
+
+    def write(self, path, data):
+        # XXX: should we use ``git add``?
+        self.normal_actions.write(path, data)
+
+    def _do(self, args):
+        _execute(['git'] + args, cwd=self.root)
+
+    def _in_dir(self, path):
+        if path.startswith(self.root):
+            return path[len(self.root) + 1:]
+        return self.root
+
+
+class DarcsCommands(object):
+
+    def __init__(self, root):
+        self.root = root
+        self.normal_actions = FileSystemCommands()
+
+    def create_file(self, path):
+        self.normal_actions.create_file(path)
+        self._do(['add', path])
+
+    def create_folder(self, path):
+        self.normal_actions.create_folder(path)
+        self._do(['add', path])
+
+    def move(self, path, new_location):
+        self._do(['mv', path, new_location])
+
+    def remove(self, path):
+        self.normal_actions.remove(path)
+
+    def write(self, path, data):
+        self.normal_actions.write(path, data)
+
+    def _do(self, args):
+        _execute(['darcs'] + args, cwd=self.root)
+
+
+def _execute(args, cwd=None):
+    process = subprocess.Popen(args, cwd=cwd, stdout=subprocess.PIPE)
+    process.wait()
+    return process.returncode
+
+
+def unicode_to_file_data(contents, encoding=None):
+    if not isinstance(contents, unicode):
+        return contents
+    if encoding is None:
+        encoding = read_str_coding(contents)
+    if encoding is not None:
+        return contents.encode(encoding)
+    try:
+        return contents.encode()
+    except UnicodeEncodeError:
+        return contents.encode('utf-8')
+
+
+def file_data_to_unicode(data, encoding=None):
+    result = _decode_data(data, encoding)
+    if '\r' in result:
+        result = result.replace('\r\n', '\n').replace('\r', '\n')
+    return result
+
+
+def _decode_data(data, encoding):
+    if isinstance(data, unicode):
+        return data
+    if encoding is None:
+        encoding = read_str_coding(data)
+    if encoding is None:
+        # there is no encoding tip, we need to guess.
+        # PEP263 says that "encoding not explicitly defined" means it is ascii,
+        # but we will use utf8 instead since utf8 fully covers ascii and btw is
+        # the only non-latin sane encoding.
+        encoding = 'utf-8'
+    try:
+        return data.decode(encoding)
+    except (UnicodeError, LookupError):
+        # fallback to latin1: it should never fail
+        return data.decode('latin1')
+
+
+def read_file_coding(path):
+    file = open(path, 'b')
+    count = 0
+    result = []
+    while True:
+        current = file.read(10)
+        if not current:
+            break
+        count += current.count('\n')
+        result.append(current)
+    file.close()
+    return _find_coding(''.join(result))
+
+
+def read_str_coding(source):
+    if type(source) == bytes:
+        newline = b'\n'
+    else:
+        newline = '\n'
+    #try:
+    #    source = source.decode("utf-8")
+    #except AttributeError:
+    #    pass
+    try:
+        first = source.index(newline) + 1
+        second = source.index(newline, first) + 1
+    except ValueError:
+        second = len(source)
+    return _find_coding(source[:second])
+
+
+def _find_coding(text):
+    if type(text) == bytes:
+        coding = b'coding'
+    else:
+        coding = "coding"
+    try:
+        start = text.index(coding) + len(coding)
+        if text[start] not in '=:':
+            return
+        start += 1
+        while start < len(text) and text[start].isspace():
+            start += 1
+        end = start
+        while end < len(text):
+            c = text[end]
+            if not c.isalnum() and c not in '-_':
+                break
+            end += 1
+        return text[start:end]
+    except ValueError:
+        pass