Finer error message for missing submodule

Author: dahlia

MANIFEST.in

@@ -1,9 +1,9 @@
-include *.h
-include *.hpp
-include *.cpp
-include Makefile
-include Makefile.am
-include utf8/*.h
+include libsass/*.h
+include libsass/*.hpp
+include libsass/*.cpp
+include libsass/Makefile
+include libsass/Makefile.am
+include libsass/utf8/*.h
 include win32/*.h
 include test/*.scss
 include README.rst

setup.py

@@ -29,6 +29,13 @@
 ''', re.VERBOSE)
 
 
+if not os.path.isdir(LIBSASS_DIR) and os.path.isdir('.git'):
+    print(file=sys.stderr)
+    print('You seem to miss initializing submodules; '
+          'try the following command', file=sys.stderr)
+    print('  git submodule update --init', file=sys.stderr)
+    print(file=sys.stderr)
+
 libsass_sources = set()
 for makefilename in [
         os.path.join(LIBSASS_DIR, 'Makefile'),