Example of refactoring using rope library.

tools/telemetry/third_party/rope/rope/contrib/generate.py

Index: tools/telemetry/third_party/rope/rope/contrib/generate.py
diff --git a/tools/telemetry/third_party/rope/rope/contrib/generate.py b/tools/telemetry/third_party/rope/rope/contrib/generate.py
new file mode 100644
index 0000000000000000000000000000000000000000..825f26d6ddad24bb4fc2b5068884631ebb89580a
--- /dev/null
+++ b/tools/telemetry/third_party/rope/rope/contrib/generate.py
@@ -0,0 +1,362 @@
+import rope.base.evaluate
+from rope.base import libutils
+from rope.base import (change, pyobjects, exceptions, pynames, worder,
+                       codeanalyze)
+from rope.refactor import sourceutils, importutils, functionutils, suites
+
+
+def create_generate(kind, project, resource, offset):
+    """A factory for creating `Generate` objects
+
+    `kind` can be 'variable', 'function', 'class', 'module' or
+    'package'.
+
+    """
+    generate = eval('Generate' + kind.title())
+    return generate(project, resource, offset)
+
+
+def create_module(project, name, sourcefolder=None):
+    """Creates a module and returns a `rope.base.resources.File`"""
+    if sourcefolder is None:
+        sourcefolder = project.root
+    packages = name.split('.')
+    parent = sourcefolder
+    for package in packages[:-1]:
+        parent = parent.get_child(package)
+    return parent.create_file(packages[-1] + '.py')
+
+
+def create_package(project, name, sourcefolder=None):
+    """Creates a package and returns a `rope.base.resources.Folder`"""
+    if sourcefolder is None:
+        sourcefolder = project.root
+    packages = name.split('.')
+    parent = sourcefolder
+    for package in packages[:-1]:
+        parent = parent.get_child(package)
+    made_packages = parent.create_folder(packages[-1])
+    made_packages.create_file('__init__.py')
+    return made_packages
+
+
+class _Generate(object):
+
+    def __init__(self, project, resource, offset):
+        self.project = project
+        self.resource = resource
+        self.info = self._generate_info(project, resource, offset)
+        self.name = self.info.get_name()
+        self._check_exceptional_conditions()
+
+    def _generate_info(self, project, resource, offset):
+        return _GenerationInfo(project.pycore, resource, offset)
+
+    def _check_exceptional_conditions(self):
+        if self.info.element_already_exists():
+            raise exceptions.RefactoringError(
+                'Element <%s> already exists.' % self.name)
+        if not self.info.primary_is_found():
+            raise exceptions.RefactoringError(
+                'Cannot determine the scope <%s> should be defined in.' %
+                self.name)
+
+    def get_changes(self):
+        changes = change.ChangeSet('Generate %s <%s>' %
+                                   (self._get_element_kind(), self.name))
+        indents = self.info.get_scope_indents()
+        blanks = self.info.get_blank_lines()
+        base_definition = sourceutils.fix_indentation(self._get_element(),
+                                                      indents)
+        definition = '\n' * blanks[0] + base_definition + '\n' * blanks[1]
+
+        resource = self.info.get_insertion_resource()
+        start, end = self.info.get_insertion_offsets()
+
+        collector = codeanalyze.ChangeCollector(resource.read())
+        collector.add_change(start, end, definition)
+        changes.add_change(change.ChangeContents(
+                           resource, collector.get_changed()))
+        return changes
+
+    def get_location(self):
+        return (self.info.get_insertion_resource(),
+                self.info.get_insertion_lineno())
+
+    def _get_element_kind(self):
+        raise NotImplementedError()
+
+    def _get_element(self):
+        raise NotImplementedError()
+
+
+class GenerateFunction(_Generate):
+
+    def _generate_info(self, project, resource, offset):
+        return _FunctionGenerationInfo(project.pycore, resource, offset)
+
+    def _get_element(self):
+        decorator = ''
+        args = []
+        if self.info.is_static_method():
+            decorator = '@staticmethod\n'
+        if self.info.is_method() or self.info.is_constructor() or \
+           self.info.is_instance():
+            args.append('self')
+        args.extend(self.info.get_passed_args())
+        definition = '%sdef %s(%s):\n    pass\n' % (decorator, self.name,
+                                                    ', '.join(args))
+        return definition
+
+    def _get_element_kind(self):
+        return 'Function'
+
+
+class GenerateVariable(_Generate):
+
+    def _get_element(self):
+        return '%s = None\n' % self.name
+
+    def _get_element_kind(self):
+        return 'Variable'
+
+
+class GenerateClass(_Generate):
+
+    def _get_element(self):
+        return 'class %s(object):\n    pass\n' % self.name
+
+    def _get_element_kind(self):
+        return 'Class'
+
+
+class GenerateModule(_Generate):
+
+    def get_changes(self):
+        package = self.info.get_package()
+        changes = change.ChangeSet('Generate Module <%s>' % self.name)
+        new_resource = self.project.get_file('%s/%s.py' %
+                                             (package.path, self.name))
+        if new_resource.exists():
+            raise exceptions.RefactoringError(
+                'Module <%s> already exists' % new_resource.path)
+        changes.add_change(change.CreateResource(new_resource))
+        changes.add_change(_add_import_to_module(
+                           self.project, self.resource, new_resource))
+        return changes
+
+    def get_location(self):
+        package = self.info.get_package()
+        return (package.get_child('%s.py' % self.name), 1)
+
+
+class GeneratePackage(_Generate):
+
+    def get_changes(self):
+        package = self.info.get_package()
+        changes = change.ChangeSet('Generate Package <%s>' % self.name)
+        new_resource = self.project.get_folder('%s/%s' %
+                                               (package.path, self.name))
+        if new_resource.exists():
+            raise exceptions.RefactoringError(
+                'Package <%s> already exists' % new_resource.path)
+        changes.add_change(change.CreateResource(new_resource))
+        changes.add_change(_add_import_to_module(
+                           self.project, self.resource, new_resource))
+        child = self.project.get_folder(package.path + '/' + self.name)
+        changes.add_change(change.CreateFile(child, '__init__.py'))
+        return changes
+
+    def get_location(self):
+        package = self.info.get_package()
+        child = package.get_child(self.name)
+        return (child.get_child('__init__.py'), 1)
+
+
+def _add_import_to_module(project, resource, imported):
+    pymodule = project.get_pymodule(resource)
+    import_tools = importutils.ImportTools(project)
+    module_imports = import_tools.module_imports(pymodule)
+    module_name = libutils.modname(imported)
+    new_import = importutils.NormalImport(((module_name, None), ))
+    module_imports.add_import(new_import)
+    return change.ChangeContents(resource, module_imports.get_changed_source())
+
+
+class _GenerationInfo(object):
+
+    def __init__(self, pycore, resource, offset):
+        self.pycore = pycore
+        self.resource = resource
+        self.offset = offset
+        self.source_pymodule = self.pycore.project.get_pymodule(resource)
+        finder = rope.base.evaluate.ScopeNameFinder(self.source_pymodule)
+        self.primary, self.pyname = finder.get_primary_and_pyname_at(offset)
+        self._init_fields()
+
+    def _init_fields(self):
+        self.source_scope = self._get_source_scope()
+        self.goal_scope = self._get_goal_scope()
+        self.goal_pymodule = self._get_goal_module(self.goal_scope)
+
+    def _get_goal_scope(self):
+        if self.primary is None:
+            return self._get_source_scope()
+        pyobject = self.primary.get_object()
+        if isinstance(pyobject, pyobjects.PyDefinedObject):
+            return pyobject.get_scope()
+        elif isinstance(pyobject.get_type(), pyobjects.PyClass):
+            return pyobject.get_type().get_scope()
+
+    def _get_goal_module(self, scope):
+        if scope is None:
+            return
+        while scope.parent is not None:
+            scope = scope.parent
+        return scope.pyobject
+
+    def _get_source_scope(self):
+        module_scope = self.source_pymodule.get_scope()
+        lineno = self.source_pymodule.lines.get_line_number(self.offset)
+        return module_scope.get_inner_scope_for_line(lineno)
+
+    def get_insertion_lineno(self):
+        lines = self.goal_pymodule.lines
+        if self.goal_scope == self.source_scope:
+            line_finder = self.goal_pymodule.logical_lines
+            lineno = lines.get_line_number(self.offset)
+            lineno = line_finder.logical_line_in(lineno)[0]
+            root = suites.ast_suite_tree(self.goal_scope.pyobject.get_ast())
+            suite = root.find_suite(lineno)
+            indents = sourceutils.get_indents(lines, lineno)
+            while self.get_scope_indents() < indents:
+                lineno = suite.get_start()
+                indents = sourceutils.get_indents(lines, lineno)
+                suite = suite.parent
+            return lineno
+        else:
+            return min(self.goal_scope.get_end() + 1, lines.length())
+
+    def get_insertion_resource(self):
+        return self.goal_pymodule.get_resource()
+
+    def get_insertion_offsets(self):
+        if self.goal_scope.get_kind() == 'Class':
+            start, end = sourceutils.get_body_region(self.goal_scope.pyobject)
+            if self.goal_pymodule.source_code[start:end].strip() == 'pass':
+                return start, end
+        lines = self.goal_pymodule.lines
+        start = lines.get_line_start(self.get_insertion_lineno())
+        return (start, start)
+
+    def get_scope_indents(self):
+        if self.goal_scope.get_kind() == 'Module':
+            return 0
+        return sourceutils.get_indents(self.goal_pymodule.lines,
+                                       self.goal_scope.get_start()) + 4
+
+    def get_blank_lines(self):
+        if self.goal_scope.get_kind() == 'Module':
+            base_blanks = 2
+            if self.goal_pymodule.source_code.strip() == '':
+                base_blanks = 0
+        if self.goal_scope.get_kind() == 'Class':
+            base_blanks = 1
+        if self.goal_scope.get_kind() == 'Function':
+            base_blanks = 0
+        if self.goal_scope == self.source_scope:
+            return (0, base_blanks)
+        return (base_blanks, 0)
+
+    def get_package(self):
+        primary = self.primary
+        if self.primary is None:
+            return self.pycore.project.get_source_folders()[0]
+        if isinstance(primary.get_object(), pyobjects.PyPackage):
+            return primary.get_object().get_resource()
+        raise exceptions.RefactoringError(
+            'A module/package can be only created in a package.')
+
+    def primary_is_found(self):
+        return self.goal_scope is not None
+
+    def element_already_exists(self):
+        if self.pyname is None or isinstance(self.pyname, pynames.UnboundName):
+            return False
+        return self.get_name() in self.goal_scope.get_defined_names()
+
+    def get_name(self):
+        return worder.get_name_at(self.resource, self.offset)
+
+
+class _FunctionGenerationInfo(_GenerationInfo):
+
+    def _get_goal_scope(self):
+        if self.is_constructor():
+            return self.pyname.get_object().get_scope()
+        if self.is_instance():
+            return self.pyname.get_object().get_type().get_scope()
+        if self.primary is None:
+            return self._get_source_scope()
+        pyobject = self.primary.get_object()
+        if isinstance(pyobject, pyobjects.PyDefinedObject):
+            return pyobject.get_scope()
+        elif isinstance(pyobject.get_type(), pyobjects.PyClass):
+            return pyobject.get_type().get_scope()
+
+    def element_already_exists(self):
+        if self.pyname is None or isinstance(self.pyname, pynames.UnboundName):
+            return False
+        return self.get_name() in self.goal_scope.get_defined_names()
+
+    def is_static_method(self):
+        return self.primary is not None and \
+            isinstance(self.primary.get_object(), pyobjects.PyClass)
+
+    def is_method(self):
+        return self.primary is not None and \
+            isinstance(self.primary.get_object().get_type(), pyobjects.PyClass)
+
+    def is_constructor(self):
+        return self.pyname is not None and \
+            isinstance(self.pyname.get_object(), pyobjects.PyClass)
+
+    def is_instance(self):
+        if self.pyname is None:
+            return False
+        pyobject = self.pyname.get_object()
+        return isinstance(pyobject.get_type(), pyobjects.PyClass)
+
+    def get_name(self):
+        if self.is_constructor():
+            return '__init__'
+        if self.is_instance():
+            return '__call__'
+        return worder.get_name_at(self.resource, self.offset)
+
+    def get_passed_args(self):
+        result = []
+        source = self.source_pymodule.source_code
+        finder = worder.Worder(source)
+        if finder.is_a_function_being_called(self.offset):
+            start, end = finder.get_primary_range(self.offset)
+            parens_start, parens_end = finder.get_word_parens_range(end - 1)
+            call = source[start:parens_end]
+            parser = functionutils._FunctionParser(call, False)
+            args, keywords = parser.get_parameters()
+            for arg in args:
+                if self._is_id(arg):
+                    result.append(arg)
+                else:
+                    result.append('arg%d' % len(result))
+            for name, value in keywords:
+                result.append(name)
+        return result
+
+    def _is_id(self, arg):
+        def id_or_underline(c):
+            return c.isalpha() or c == '_'
+        for c in arg:
+            if not id_or_underline(c) and not c.isdigit():
+                return False
+        return id_or_underline(arg[0])