Example of refactoring using rope library.

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

Index: tools/telemetry/third_party/rope/rope/base/taskhandle.py
diff --git a/tools/telemetry/third_party/rope/rope/base/taskhandle.py b/tools/telemetry/third_party/rope/rope/base/taskhandle.py
new file mode 100644
index 0000000000000000000000000000000000000000..c1f01b984399454ca6ad6a095e83905904035a0e
--- /dev/null
+++ b/tools/telemetry/third_party/rope/rope/base/taskhandle.py
@@ -0,0 +1,131 @@
+from rope.base import exceptions
+
+
+class TaskHandle(object):
+
+    def __init__(self, name='Task', interrupts=True):
+        """Construct a TaskHandle
+
+        If `interrupts` is `False` the task won't be interrupted by
+        calling `TaskHandle.stop()`.
+
+        """
+        self.name = name
+        self.interrupts = interrupts
+        self.stopped = False
+        self.job_sets = []
+        self.observers = []
+
+    def stop(self):
+        """Interrupts the refactoring"""
+        if self.interrupts:
+            self.stopped = True
+            self._inform_observers()
+
+    def current_jobset(self):
+        """Return the current `JobSet`"""
+        if self.job_sets:
+            return self.job_sets[-1]
+
+    def add_observer(self, observer):
+        """Register an observer for this task handle
+
+        The observer is notified whenever the task is stopped or
+        a job gets finished.
+
+        """
+        self.observers.append(observer)
+
+    def is_stopped(self):
+        return self.stopped
+
+    def get_jobsets(self):
+        return self.job_sets
+
+    def create_jobset(self, name='JobSet', count=None):
+        result = JobSet(self, name=name, count=count)
+        self.job_sets.append(result)
+        self._inform_observers()
+        return result
+
+    def _inform_observers(self):
+        for observer in list(self.observers):
+            observer()
+
+
+class JobSet(object):
+
+    def __init__(self, handle, name, count):
+        self.handle = handle
+        self.name = name
+        self.count = count
+        self.done = 0
+        self.job_name = None
+
+    def started_job(self, name):
+        self.check_status()
+        self.job_name = name
+        self.handle._inform_observers()
+
+    def finished_job(self):
+        self.check_status()
+        self.done += 1
+        self.handle._inform_observers()
+        self.job_name = None
+
+    def check_status(self):
+        if self.handle.is_stopped():
+            raise exceptions.InterruptedTaskError()
+
+    def get_active_job_name(self):
+        return self.job_name
+
+    def get_percent_done(self):
+        if self.count is not None and self.count > 0:
+            percent = self.done * 100 // self.count
+            return min(percent, 100)
+
+    def get_name(self):
+        return self.name
+
+
+class NullTaskHandle(object):
+
+    def __init__(self):
+        pass
+
+    def is_stopped(self):
+        return False
+
+    def stop(self):
+        pass
+
+    def create_jobset(self, *args, **kwds):
+        return NullJobSet()
+
+    def get_jobsets(self):
+        return []
+
+    def add_observer(self, observer):
+        pass
+
+
+class NullJobSet(object):
+
+    def started_job(self, name):
+        pass
+
+    def finished_job(self):
+        pass
+
+    def check_status(self):
+        pass
+
+    def get_active_job_name(self):
+        pass
+
+    def get_percent_done(self):
+        pass
+
+    def get_name(self):
+        pass