Merge pull request #119 from olajep/let-local-conf-override-global

Let local YCM config file override global config file

README.md

@@ -314,7 +314,7 @@ or in any directory above it in the hierarchy (recursively); when the file is
 found, it is loaded (only once!) as a Python module. YCM calls a `FlagsForFile`
 method in that module which should provide it with the information necessary to
 compile the current file. (You can also provide a path to a global
-`.ycm_extra_conf.py` file and override this searching behavior. See the Options
+`.ycm_extra_conf.py` file, which will be used as a fallback. See the Options
 section for more details.)
 
 This system was designed this way so that the user can perform any arbitrary
@@ -640,11 +640,10 @@ Default: `<leader>d`
 
 ### The `g:ycm_global_ycm_extra_conf` option
 
-Normally, YCM searches for a `.ycm_extra_conf.py` file for compilation flags
-(see the User Guide for more details on how this works). You can use this option
-to override this searching behavior by providing a full, absolute path to a
-global `.ycm_extra_conf.py` file (although you can call the global file whatever
-you want).
+Normally, YCM searches for a '.ycm_extra_conf.py' file for compilation flags
+(see the User Guide for more details on how this works). This option specifies
+a fallback path to a config file which is used if no '.ycm_extra_conf.py' is
+found.
 
 You can place such a global file anywhere in your filesystem.
 

doc/youcompleteme.txt

@@ -717,10 +717,9 @@ Default: '<leader>d'
 The *g:ycm_global_ycm_extra_conf* option
 
 Normally, YCM searches for a '.ycm_extra_conf.py' file for compilation flags
-(see the User Guide for more details on how this works). You can use this
-option to override this searching behavior by providing a full, absolute path
-to a global '.ycm_extra_conf.py' file (although you can call the global file
-whatever you want).
+(see the User Guide for more details on how this works). This option specifies
+a fallback path to a config file which is used if no '.ycm_extra_conf.py' is
+found.
 
 You can place such a global file anywhere in your filesystem.
 

python/completers/cpp/flags.py

@@ -92,27 +92,31 @@ class Flags( object ):
 
 def _FlagsModuleSourceFileForFile( filename ):
   """For a given filename, finds its nearest YCM_EXTRA_CONF_FILENAME file that
-  will compute the flags necessary to compile the file. Returns None if no
-  YCM_EXTRA_CONF_FILENAME file could be found. Uses the global ycm_extra_conf
-  file if one is set."""
-
-  if ( GLOBAL_YCM_EXTRA_CONF_FILE and
-       os.path.exists( GLOBAL_YCM_EXTRA_CONF_FILE ) ):
-    return GLOBAL_YCM_EXTRA_CONF_FILE
+  will compute the flags necessary to compile the file. If no
+  YCM_EXTRA_CONF_FILENAME file could be found, try to use
+  GLOBAL_YCM_EXTRA_CONF_FILE instead. If that also fails, return None.
+  Uses the global ycm_extra_conf file if one is set."""
 
+  ycm_conf_file = None
   parent_folder = os.path.dirname( filename )
   old_parent_folder = ''
 
   while True:
     current_file = os.path.join( parent_folder, YCM_EXTRA_CONF_FILENAME )
     if os.path.exists( current_file ):
-      return current_file
+      ycm_conf_file = current_file
+      break
 
     old_parent_folder = parent_folder
     parent_folder = os.path.dirname( parent_folder )
+    if parent_folder is old_parent_folder:
+      break
 
-    if parent_folder == old_parent_folder:
-      return None
+  if ( not ycm_conf_file and GLOBAL_YCM_EXTRA_CONF_FILE and
+       os.path.exists( GLOBAL_YCM_EXTRA_CONF_FILE ) ):
+    ycm_conf_file = GLOBAL_YCM_EXTRA_CONF_FILE
+
+  return ycm_conf_file
 
 
 def _RandomName():