Example of refactoring using rope library.

tools/telemetry/third_party/rope/rope/base/oi/transform.py

Index: tools/telemetry/third_party/rope/rope/base/oi/transform.py
diff --git a/tools/telemetry/third_party/rope/rope/base/oi/transform.py b/tools/telemetry/third_party/rope/rope/base/oi/transform.py
new file mode 100644
index 0000000000000000000000000000000000000000..aa29c373d5cb34e24994ed2e43c86f0a080276a0
--- /dev/null
+++ b/tools/telemetry/third_party/rope/rope/base/oi/transform.py
@@ -0,0 +1,285 @@
+"""Provides classes for persisting `PyObject`\s"""
+import os
+import re
+
+import rope.base.builtins
+from rope.base import exceptions
+
+
+class PyObjectToTextual(object):
+    """For transforming `PyObject` to textual form
+
+    This can be used for storing `PyObjects` in files.  Use
+    `TextualToPyObject` for converting back.
+
+    """
+
+    def __init__(self, project):
+        self.project = project
+
+    def transform(self, pyobject):
+        """Transform a `PyObject` to textual form"""
+        if pyobject is None:
+            return ('none',)
+        object_type = type(pyobject)
+        try:
+            method = getattr(self, object_type.__name__ + '_to_textual')
+            return method(pyobject)
+        except AttributeError:
+            return ('unknown',)
+
+    def __call__(self, pyobject):
+        return self.transform(pyobject)
+
+    def PyObject_to_textual(self, pyobject):
+        if isinstance(pyobject.get_type(), rope.base.pyobjects.AbstractClass):
+            result = self.transform(pyobject.get_type())
+            if result[0] == 'defined':
+                return ('instance', result)
+            return result
+        return ('unknown',)
+
+    def PyFunction_to_textual(self, pyobject):
+        return self._defined_to_textual(pyobject)
+
+    def PyClass_to_textual(self, pyobject):
+        return self._defined_to_textual(pyobject)
+
+    def _defined_to_textual(self, pyobject):
+        address = []
+        while pyobject.parent is not None:
+            address.insert(0, pyobject.get_name())
+            pyobject = pyobject.parent
+        return ('defined', self._get_pymodule_path(pyobject.get_module()),
+                '.'.join(address))
+
+    def PyModule_to_textual(self, pyobject):
+        return ('defined', self._get_pymodule_path(pyobject))
+
+    def PyPackage_to_textual(self, pyobject):
+        return ('defined', self._get_pymodule_path(pyobject))
+
+    def List_to_textual(self, pyobject):
+        return ('builtin', 'list', self.transform(pyobject.holding))
+
+    def Dict_to_textual(self, pyobject):
+        return ('builtin', 'dict', self.transform(pyobject.keys),
+                self.transform(pyobject.values))
+
+    def Tuple_to_textual(self, pyobject):
+        objects = [self.transform(holding)
+                   for holding in pyobject.get_holding_objects()]
+        return tuple(['builtin', 'tuple'] + objects)
+
+    def Set_to_textual(self, pyobject):
+        return ('builtin', 'set', self.transform(pyobject.holding))
+
+    def Iterator_to_textual(self, pyobject):
+        return ('builtin', 'iter', self.transform(pyobject.holding))
+
+    def Generator_to_textual(self, pyobject):
+        return ('builtin', 'generator', self.transform(pyobject.holding))
+
+    def Str_to_textual(self, pyobject):
+        return ('builtin', 'str')
+
+    def File_to_textual(self, pyobject):
+        return ('builtin', 'file')
+
+    def BuiltinFunction_to_textual(self, pyobject):
+        return ('builtin', 'function', pyobject.get_name())
+
+    def _get_pymodule_path(self, pymodule):
+        return self.resource_to_path(pymodule.get_resource())
+
+    def resource_to_path(self, resource):
+        if resource.project == self.project:
+            return resource.path
+        else:
+            return resource.real_path
+
+
+class TextualToPyObject(object):
+    """For transforming textual form to `PyObject`"""
+
+    def __init__(self, project, allow_in_project_absolutes=False):
+        self.project = project
+
+    def __call__(self, textual):
+        return self.transform(textual)
+
+    def transform(self, textual):
+        """Transform an object from textual form to `PyObject`"""
+        if textual is None:
+            return None
+        type = textual[0]
+        try:
+            method = getattr(self, type + '_to_pyobject')
+            return method(textual)
+        except AttributeError:
+            return None
+
+    def builtin_to_pyobject(self, textual):
+        method = getattr(self, 'builtin_%s_to_pyobject' % textual[1], None)
+        if method is not None:
+            return method(textual)
+
+    def builtin_str_to_pyobject(self, textual):
+        return rope.base.builtins.get_str()
+
+    def builtin_list_to_pyobject(self, textual):
+        holding = self.transform(textual[2])
+        return rope.base.builtins.get_list(holding)
+
+    def builtin_dict_to_pyobject(self, textual):
+        keys = self.transform(textual[2])
+        values = self.transform(textual[3])
+        return rope.base.builtins.get_dict(keys, values)
+
+    def builtin_tuple_to_pyobject(self, textual):
+        objects = []
+        for holding in textual[2:]:
+            objects.append(self.transform(holding))
+        return rope.base.builtins.get_tuple(*objects)
+
+    def builtin_set_to_pyobject(self, textual):
+        holding = self.transform(textual[2])
+        return rope.base.builtins.get_set(holding)
+
+    def builtin_iter_to_pyobject(self, textual):
+        holding = self.transform(textual[2])
+        return rope.base.builtins.get_iterator(holding)
+
+    def builtin_generator_to_pyobject(self, textual):
+        holding = self.transform(textual[2])
+        return rope.base.builtins.get_generator(holding)
+
+    def builtin_file_to_pyobject(self, textual):
+        return rope.base.builtins.get_file()
+
+    def builtin_function_to_pyobject(self, textual):
+        if textual[2] in rope.base.builtins.builtins:
+            return rope.base.builtins.builtins[textual[2]].get_object()
+
+    def unknown_to_pyobject(self, textual):
+        return None
+
+    def none_to_pyobject(self, textual):
+        return None
+
+    def _module_to_pyobject(self, textual):
+        path = textual[1]
+        return self._get_pymodule(path)
+
+    def _hierarchical_defined_to_pyobject(self, textual):
+        path = textual[1]
+        names = textual[2].split('.')
+        pymodule = self._get_pymodule(path)
+        pyobject = pymodule
+        for name in names:
+            if pyobject is None:
+                return None
+            if isinstance(pyobject, rope.base.pyobjects.PyDefinedObject):
+                try:
+                    pyobject = pyobject.get_scope()[name].get_object()
+                except exceptions.NameNotFoundError:
+                    return None
+            else:
+                return None
+        return pyobject
+
+    def defined_to_pyobject(self, textual):
+        if len(textual) == 2 or textual[2] == '':
+            return self._module_to_pyobject(textual)
+        else:
+            return self._hierarchical_defined_to_pyobject(textual)
+
+    def instance_to_pyobject(self, textual):
+        type = self.transform(textual[1])
+        if type is not None:
+            return rope.base.pyobjects.PyObject(type)
+
+    def _get_pymodule(self, path):
+        resource = self.path_to_resource(path)
+        if resource is not None:
+            return self.project.get_pymodule(resource)
+
+    def path_to_resource(self, path):
+        try:
+            root = self.project.address
+            if not os.path.isabs(path):
+                return self.project.get_resource(path)
+            if path == root or path.startswith(root + os.sep):
+                # INFO: This is a project file; should not be absolute
+                return None
+            import rope.base.project
+            return rope.base.project.get_no_project().get_resource(path)
+        except exceptions.ResourceNotFoundError:
+            return None
+
+
+class DOITextualToPyObject(TextualToPyObject):
+    """For transforming textual form to `PyObject`
+
+    The textual form DOI uses is different from rope's standard
+    textual form.  The reason is that we cannot find the needed
+    information by analyzing live objects.  This class can be
+    used to transform DOI textual form to `PyObject` and later
+    we can convert it to standard textual form using
+    `TextualToPyObject` class.
+
+    """
+
+    def _function_to_pyobject(self, textual):
+        path = textual[1]
+        lineno = int(textual[2])
+        pymodule = self._get_pymodule(path)
+        if pymodule is not None:
+            scope = pymodule.get_scope()
+            inner_scope = scope.get_inner_scope_for_line(lineno)
+            return inner_scope.pyobject
+
+    def _class_to_pyobject(self, textual):
+        path, name = textual[1:]
+        pymodule = self._get_pymodule(path)
+        if pymodule is None:
+            return None
+        module_scope = pymodule.get_scope()
+        suspected = None
+        if name in module_scope.get_names():
+            suspected = module_scope[name].get_object()
+        if suspected is not None and \
+           isinstance(suspected, rope.base.pyobjects.PyClass):
+            return suspected
+        else:
+            lineno = self._find_occurrence(name,
+                                           pymodule.get_resource().read())
+            if lineno is not None:
+                inner_scope = module_scope.get_inner_scope_for_line(lineno)
+                return inner_scope.pyobject
+
+    def defined_to_pyobject(self, textual):
+        if len(textual) == 2:
+            return self._module_to_pyobject(textual)
+        else:
+            if textual[2].isdigit():
+                result = self._function_to_pyobject(textual)
+            else:
+                result = self._class_to_pyobject(textual)
+            if not isinstance(result, rope.base.pyobjects.PyModule):
+                return result
+
+    def _find_occurrence(self, name, source):
+        pattern = re.compile(r'^\s*class\s*' + name + r'\b')
+        lines = source.split('\n')
+        for i in range(len(lines)):
+            if pattern.match(lines[i]):
+                return i + 1
+
+    def path_to_resource(self, path):
+        import rope.base.libutils
+        relpath = rope.base.libutils.path_relative_to_project_root(
+            self.project, path)
+        if relpath is not None:
+            path = relpath
+        return super(DOITextualToPyObject, self).path_to_resource(path)