Example of refactoring using rope library.

tools/telemetry/third_party/rope/rope/refactor/importutils/importinfo.py

Index: tools/telemetry/third_party/rope/rope/refactor/importutils/importinfo.py
diff --git a/tools/telemetry/third_party/rope/rope/refactor/importutils/importinfo.py b/tools/telemetry/third_party/rope/rope/refactor/importutils/importinfo.py
new file mode 100644
index 0000000000000000000000000000000000000000..114080aac486abddf7e14025bc97733e7177ab70
--- /dev/null
+++ b/tools/telemetry/third_party/rope/rope/refactor/importutils/importinfo.py
@@ -0,0 +1,201 @@
+class ImportStatement(object):
+    """Represent an import in a module
+
+    `readonly` attribute controls whether this import can be changed
+    by import actions or not.
+
+    """
+
+    def __init__(self, import_info, start_line, end_line,
+                 main_statement=None, blank_lines=0):
+        self.start_line = start_line
+        self.end_line = end_line
+        self.readonly = False
+        self.main_statement = main_statement
+        self._import_info = None
+        self.import_info = import_info
+        self._is_changed = False
+        self.new_start = None
+        self.blank_lines = blank_lines
+
+    def _get_import_info(self):
+        return self._import_info
+
+    def _set_import_info(self, new_import):
+        if not self.readonly and \
+           new_import is not None and not new_import == self._import_info:
+            self._is_changed = True
+            self._import_info = new_import
+
+    import_info = property(_get_import_info, _set_import_info)
+
+    def get_import_statement(self):
+        if self._is_changed or self.main_statement is None:
+            return self.import_info.get_import_statement()
+        else:
+            return self.main_statement
+
+    def empty_import(self):
+        self.import_info = ImportInfo.get_empty_import()
+
+    def move(self, lineno, blank_lines=0):
+        self.new_start = lineno
+        self.blank_lines = blank_lines
+
+    def get_old_location(self):
+        return self.start_line, self.end_line
+
+    def get_new_start(self):
+        return self.new_start
+
+    def is_changed(self):
+        return self._is_changed or (self.new_start is not None or
+                                    self.new_start != self.start_line)
+
+    def accept(self, visitor):
+        return visitor.dispatch(self)
+
+
+class ImportInfo(object):
+
+    def get_imported_primaries(self, context):
+        pass
+
+    def get_imported_names(self, context):
+        return [primary.split('.')[0]
+                for primary in self.get_imported_primaries(context)]
+
+    def get_import_statement(self):
+        pass
+
+    def is_empty(self):
+        pass
+
+    def __hash__(self):
+        return hash(self.get_import_statement())
+
+    def _are_name_and_alias_lists_equal(self, list1, list2):
+        if len(list1) != len(list2):
+            return False
+        for pair1, pair2 in zip(list1, list2):
+            if pair1 != pair2:
+                return False
+        return True
+
+    def __eq__(self, obj):
+        return isinstance(obj, self.__class__) and \
+            self.get_import_statement() == obj.get_import_statement()
+
+    def __ne__(self, obj):
+        return not self.__eq__(obj)
+
+    @staticmethod
+    def get_empty_import():
+        return EmptyImport()
+
+
+class NormalImport(ImportInfo):
+
+    def __init__(self, names_and_aliases):
+        self.names_and_aliases = names_and_aliases
+
+    def get_imported_primaries(self, context):
+        result = []
+        for name, alias in self.names_and_aliases:
+            if alias:
+                result.append(alias)
+            else:
+                result.append(name)
+        return result
+
+    def get_import_statement(self):
+        result = 'import '
+        for name, alias in self.names_and_aliases:
+            result += name
+            if alias:
+                result += ' as ' + alias
+            result += ', '
+        return result[:-2]
+
+    def is_empty(self):
+        return len(self.names_and_aliases) == 0
+
+
+class FromImport(ImportInfo):
+
+    def __init__(self, module_name, level, names_and_aliases):
+        self.module_name = module_name
+        self.level = level
+        self.names_and_aliases = names_and_aliases
+
+    def get_imported_primaries(self, context):
+        if self.names_and_aliases[0][0] == '*':
+            module = self.get_imported_module(context)
+            return [name for name in module
+                    if not name.startswith('_')]
+        result = []
+        for name, alias in self.names_and_aliases:
+            if alias:
+                result.append(alias)
+            else:
+                result.append(name)
+        return result
+
+    def get_imported_resource(self, context):
+        """Get the imported resource
+
+        Returns `None` if module was not found.
+        """
+        if self.level == 0:
+            return context.project.find_module(
+                self.module_name, folder=context.folder)
+        else:
+            return context.project.find_relative_module(
+                self.module_name, context.folder, self.level)
+
+    def get_imported_module(self, context):
+        """Get the imported `PyModule`
+
+        Raises `rope.base.exceptions.ModuleNotFoundError` if module
+        could not be found.
+        """
+        if self.level == 0:
+            return context.project.get_module(
+                self.module_name, context.folder)
+        else:
+            return context.project.get_relative_module(
+                self.module_name, context.folder, self.level)
+
+    def get_import_statement(self):
+        result = 'from ' + '.' * self.level + self.module_name + ' import '
+        for name, alias in self.names_and_aliases:
+            result += name
+            if alias:
+                result += ' as ' + alias
+            result += ', '
+        return result[:-2]
+
+    def is_empty(self):
+        return len(self.names_and_aliases) == 0
+
+    def is_star_import(self):
+        return len(self.names_and_aliases) > 0 and \
+            self.names_and_aliases[0][0] == '*'
+
+
+class EmptyImport(ImportInfo):
+
+    names_and_aliases = []
+
+    def is_empty(self):
+        return True
+
+    def get_imported_primaries(self, context):
+        return []
+
+
+class ImportContext(object):
+
+    def __init__(self, project, folder):
+        self.project = project
+        self.folder = folder