Example of refactoring using rope library.

tools/telemetry/third_party/rope/rope/refactor/sourceutils.py

Index: tools/telemetry/third_party/rope/rope/refactor/sourceutils.py
diff --git a/tools/telemetry/third_party/rope/rope/refactor/sourceutils.py b/tools/telemetry/third_party/rope/rope/refactor/sourceutils.py
new file mode 100644
index 0000000000000000000000000000000000000000..9b842906636f5348579f796b40c6dd4a24e3d6d9
--- /dev/null
+++ b/tools/telemetry/third_party/rope/rope/refactor/sourceutils.py
@@ -0,0 +1,91 @@
+from rope.base import codeanalyze
+
+
+def get_indents(lines, lineno):
+    return codeanalyze.count_line_indents(lines.get_line(lineno))
+
+
+def find_minimum_indents(source_code):
+    result = 80
+    lines = source_code.split('\n')
+    for line in lines:
+        if line.strip() == '':
+            continue
+        result = min(result, codeanalyze.count_line_indents(line))
+    return result
+
+
+def indent_lines(source_code, amount):
+    if amount == 0:
+        return source_code
+    lines = source_code.splitlines(True)
+    result = []
+    for l in lines:
+        if l.strip() == '':
+            result.append('\n')
+            continue
+        if amount < 0:
+            indents = codeanalyze.count_line_indents(l)
+            result.append(max(0, indents + amount) * ' ' + l.lstrip())
+        else:
+            result.append(' ' * amount + l)
+    return ''.join(result)
+
+
+def fix_indentation(code, new_indents):
+    """Change the indentation of `code` to `new_indents`"""
+    min_indents = find_minimum_indents(code)
+    return indent_lines(code, new_indents - min_indents)
+
+
+def add_methods(pymodule, class_scope, methods_sources):
+    source_code = pymodule.source_code
+    lines = pymodule.lines
+    insertion_line = class_scope.get_end()
+    if class_scope.get_scopes():
+        insertion_line = class_scope.get_scopes()[-1].get_end()
+    insertion_offset = lines.get_line_end(insertion_line)
+    methods = '\n\n' + '\n\n'.join(methods_sources)
+    indented_methods = fix_indentation(
+        methods, get_indents(lines, class_scope.get_start()) +
+        get_indent(pymodule.pycore.project))
+    result = []
+    result.append(source_code[:insertion_offset])
+    result.append(indented_methods)
+    result.append(source_code[insertion_offset:])
+    return ''.join(result)
+
+
+def get_body(pyfunction):
+    """Return unindented function body"""
+    # FIXME scope = pyfunction.get_scope()
+    pymodule = pyfunction.get_module()
+    start, end = get_body_region(pyfunction)
+    return fix_indentation(pymodule.source_code[start:end], 0)
+
+
+def get_body_region(defined):
+    """Return the start and end offsets of function body"""
+    scope = defined.get_scope()
+    pymodule = defined.get_module()
+    lines = pymodule.lines
+    node = defined.get_ast()
+    start_line = node.lineno
+    if defined.get_doc() is None:
+        start_line = node.body[0].lineno
+    elif len(node.body) > 1:
+        start_line = node.body[1].lineno
+    start = lines.get_line_start(start_line)
+    scope_start = pymodule.logical_lines.logical_line_in(scope.start)
+    if scope_start[1] >= start_line:
+        # a one-liner!
+        # XXX: what if colon appears in a string
+        start = pymodule.source_code.index(':', start) + 1
+        while pymodule.source_code[start].isspace():
+            start += 1
+    end = min(lines.get_line_end(scope.end) + 1, len(pymodule.source_code))
+    return start, end
+
+
+def get_indent(project):
+    return project.prefs.get('indent_size', 4)