utility that conver's misago absolute imports to relative imports

fixabsoluteimports.py

@@ -0,0 +1,75 @@
+import os
+
+
+def walk_directory(root, dirs, files):
+    for file_path in files:
+        if 'project_template' not in root and file_path.lower().endswith('.py'):
+            clean_file(os.path.join(root, file_path))
+
+
+def clean_file(file_path):
+    py_source = file(file_path).read()
+    if 'misago.' in py_source:
+        package = file_path.rstrip('.py').split('/')[:-1]
+
+        parse_file = True
+        save_file = False
+        cursor = 0
+
+        while parse_file:
+            try:
+                import_start = py_source.index('from ', cursor)
+                import_end = py_source.index(' import', import_start)
+                cursor = import_end
+
+                import_len = import_end - import_start
+                import_path = py_source[import_start:import_end].lstrip('from').strip()
+
+                if import_path.startswith('misago.'):
+                    cleaned_import = clean_import(package, import_path.split('.'))
+                    if cleaned_import:
+                        save_file = True
+
+                        cleaned_import_string = 'from {}'.format('.'.join(cleaned_import))
+                        py_source = ''.join((py_source[:import_start], cleaned_import_string, py_source[import_end:]))
+                        cursor -= import_end - import_start - len(cleaned_import_string)
+            except ValueError:
+                parse_file = False
+
+        if save_file:
+            with open(file_path, 'w') as package:
+                print py_source
+                package.write(py_source)
+
+
+def clean_import(package, import_path):
+    if len(package) < 2 or len(import_path) < 2:
+        return
+
+    if package[:2] != import_path[:2]:
+        return
+
+    if package == import_path:
+        # import from sibling module
+        return ['', '']
+
+    if len(package) < len(import_path) and package == import_path[:len(package)]:
+        # import from child module
+        return [''] + import_path[len(package):]
+
+    # find upwards path
+    overlap_len = 2
+    while True:
+        if package[:overlap_len + 1] != import_path[:overlap_len + 1]:
+            break
+        overlap_len += 1
+
+    upward_path = (['', ''] * (len(package) - overlap_len))[:-1]
+
+    # append eventual downwards path
+    return upward_path + import_path[overlap_len:]
+
+
+if __name__ == '__main__':
+    for args in os.walk('misago'):
+        walk_directory(*args)