Calling PrepareClangFlags is not needed anymore

ycm_extra_conf.py files used to import clang_helpers and then use the
PrepareClangFlags function; this is now unnecessary since the logic from that
function has been moved to flags.py. The old PrepareClangFlags function is still
there (it just returns the flags it gets) for the sake of backwards
compatibility with old ycm_extra_conf.py files.

cpp/ycm/.ycm_extra_conf.py

@@ -30,7 +30,6 @@
 
 import os
 import ycm_core
-from clang_helpers import PrepareClangFlags
 
 # These are the compilation flags that will be used in case there's no
 # compilation database set (by default, one is not set).
@@ -134,11 +133,9 @@ def FlagsForFile( filename ):
     # Bear in mind that compilation_info.compiler_flags_ does NOT return a
     # python list, but a "list-like" StringVec object
     compilation_info = database.GetCompilationInfoForFile( filename )
-    final_flags = PrepareClangFlags(
-        MakeRelativePathsInFlagsAbsolute(
-            compilation_info.compiler_flags_,
-            compilation_info.compiler_working_dir_ ),
-        filename )
+    final_flags = MakeRelativePathsInFlagsAbsolute(
+      compilation_info.compiler_flags_,
+      compilation_info.compiler_working_dir_ )
 
     # NOTE: This is just for YouCompleteMe; it's highly likely that your project
     # does NOT need to remove the stdlib flag. DO NOT USE THIS IN YOUR

python/completers/cpp/clang_helpers.py

@@ -17,28 +17,9 @@
 # You should have received a copy of the GNU General Public License
 # along with YouCompleteMe.  If not, see <http://www.gnu.org/licenses/>.
 
-import os
 
-# Given an iterable object that produces strings (flags for Clang), removes the
-# '-c' and '-o' options that Clang does not like to see when it's producing
-# completions for a file.
+# This function doesn't do anything; it used to do something useful, but not
+# anymore. It MUST NOT be removed because of backwards compatibility with old
+# ycm_extra_conf.py files.
 def PrepareClangFlags( flags, filename ):
-  new_flags = []
-  skip = True
-  for flag in flags:
-    if skip:
-      skip = False
-      continue
-
-    if flag == '-c':
-      continue
-
-    if flag == '-o':
-      skip = True;
-      continue
-
-    if flag == filename or os.path.realpath(flag) == filename:
-      continue
-
-    new_flags.append( flag )
-  return new_flags
+  return flags

python/completers/cpp/flags.py

@@ -56,7 +56,7 @@ class Flags( object ):
 
       if add_special_clang_flags:
         results[ 'flags' ] += self.special_clang_flags
-      sanitized_flags = _SanitizeFlags( results[ 'flags' ] )
+      sanitized_flags = _PrepareFlagsForClang( results[ 'flags' ], filename )
 
       if results[ 'do_cache' ]:
         self.flags_for_file[ filename ] = sanitized_flags
@@ -88,6 +88,11 @@ class Flags( object ):
     return [ x for x in include_paths if x ]
 
 
+def _PrepareFlagsForClang( flags, filename ):
+  flags = _RemoveUnusedFlags( flags, filename )
+  flags = _SanitizeFlags( flags )
+  return flags
+
 
 def _SanitizeFlags( flags ):
   """Drops unsafe flags. Currently these are only -arch flags; they tend to
@@ -113,6 +118,32 @@ def _SanitizeFlags( flags ):
   return vector
 
 
+def _RemoveUnusedFlags( flags, filename ):
+  """Given an iterable object that produces strings (flags for Clang), removes
+  the '-c' and '-o' options that Clang does not like to see when it's producing
+  completions for a file."""
+
+  new_flags = []
+  skip = True
+  for flag in flags:
+    if skip:
+      skip = False
+      continue
+
+    if flag == '-c':
+      continue
+
+    if flag == '-o':
+      skip = True;
+      continue
+
+    if flag == filename or os.path.realpath(flag) == filename:
+      continue
+
+    new_flags.append( flag )
+  return new_flags
+
+
 def _SpecialClangIncludes():
   libclang_dir = os.path.dirname( ycm_core.__file__ )
   path_to_includes = os.path.join( libclang_dir, 'clang_includes' )

python/extra_conf_store.py

@@ -115,6 +115,10 @@ def _Load( module_file, force = False ):
     if not _ShouldLoad( module_file ):
       return _Disable( module_file )
 
+  # This has to be here because a long time ago, the ycm_extra_conf.py files
+  # used to import clang_helpers.py from the cpp folder. This is not needed
+  # anymore, but there are a lot of old ycm_extra_conf.py files that we don't
+  # want to break.
   sys.path.insert( 0, _PathToCppCompleterFolder() )
   module = imp.load_source( _RandomName(), module_file )
   del sys.path[ 0 ]