doc for msvc14_library_dir_option

setuptools/msvc.py

@@ -86,7 +86,7 @@ def patch_for_specialized_compiler():
         pass
 
     try:
-        # Patch distutils._msvccompiler.library_dir_option
+        # Patch distutils._msvccompiler.MSVCCompiler.library_dir_option
         unpatched['msvc14_library_dir_option'] = msvc14compiler.MSVCCompiler.library_dir_option
         msvc14compiler.MSVCCompiler.library_dir_option = msvc14_library_dir_option
     except Exception:
@@ -220,7 +220,21 @@ def msvc14_get_vc_env(plat_spec):
 
 
 def msvc14_library_dir_option(self, dir):
+    """
+    Patched "distutils._msvccompiler.MSVCCompiler.library_dir_option"
+    to fix unquoted path in "\LIBPATH" argument when a space is on path.
+
+    Parameters
+    ----------
+    dir: str
+        Path to convert in "\LIBPATH" argument.
+
+    Return
+    ------
+    "\LIBPATH" argument: str
+    """
     if ' ' in dir and '"' not in dir:
+        # Quote if space and not already quoted
         dir = '"%s"' % dir
     return unpatched['msvc14_library_dir_option'](self, dir)