Don't move README to index on check if there exists an index file

Related #1550.

Author: gregmuellegger

readthedocs/doc_builder/base.py

@@ -93,16 +93,14 @@ def create_index(self, extension='md', **kwargs):
         """
 
         docs_dir = self.docs_dir()
-
-        index_filename = os.path.join(docs_dir, 'index.{ext}'.format(ext=extension))
-        if not os.path.exists(index_filename):
-            readme_filename = os.path.join(docs_dir, 'README.{ext}'.format(ext=extension))
-            if os.path.exists(readme_filename):
-                os.system('mv {readme} {index}'.format(index=index_filename,
-                                                       readme=readme_filename))
-            else:
-                index_file = open(index_filename, 'w+')
-                index_text = """
+        valid_filenames = ('index', 'README')
+        index_filenames = [
+            os.path.join(docs_dir, '{filename}.{ext}'.format(
+                filename=filename, ext=extension))
+            for filename in valid_filenames]
+        if not any(os.path.exists(filename) for filename in index_filenames):
+            primary_index = index_filenames[0]
+            index_text = """
 
 Welcome to Read the Docs
 ------------------------
@@ -112,10 +110,11 @@ def create_index(self, extension='md', **kwargs):
 Please create a ``{dir}/index.{ext}`` or ``{dir}/README.{ext}`` file with your own content.
 
 If you want to use another markup, choose a different builder in your settings.
-                """
-
-                index_file.write(index_text.format(dir=docs_dir, ext=extension))
-                index_file.close()
+            """
+            with open(primary_index, 'w+') as index_file:
+                index_file.write(index_text.format(
+                    dir=docs_dir,
+                    ext=extension))
 
     def run(self, *args, **kwargs):
         '''Proxy run to build environment'''