RF(TEMP?): just ignore if some provided files are not staged

apparently add(".") would not "filter out" those which are clean and not
modified, so we might have no good chance to detect those.  What if we skip
- what will fail?

datalad/support/annexrepo.py

@@ -2785,23 +2785,29 @@ def commit(self, msg=None, options=None, _datalad_msg=False,
                     # assuming that what is to be committed is staged (!could be
                     # wrong assumption), we need to prepare a custom index, and
                     # commit without specifying any paths
-                    all_staged_files = {
-                        opj(self.path, p)
-                        for p in self.get_changed_files(staged=True)
+                    changed_files = {
+                        staged: {
+                            opj(self.path, p)
+                            for p in self.get_changed_files(staged=staged)
+                        } for staged in (True,) #  False}
                     }
                     files_set = set(files)
-                    files_notstaged = files_set.difference(all_staged_files)
-                    if files_notstaged:
-                        # To be safe(r), let's just blow for now!
-                        # We could be smart(er) and do all the git or annex add
-                        # but let's see if we run into those cases first
-                        raise RuntimeError(
-                            "To commit files in direct mode, please first git "
-                            "or git-annex add them first!  Files: %s"
-                            % ', '.join(files_notstaged)
-                        )
+                    files_notstaged = files_set.difference(changed_files[True])
+                    # Lazy .add('.') results in ALL (performance?) files listed
+                    # here even if they are not changed at all and could be ignored
+                    #files_changed_notstaged = files_notstaged.difference(changed_files[False])
+                    # if files_changed_notstaged:
+                    #     # To be safe(r), let's just blow for now!
+                    #     # We could be smart(er) and do all the git or annex add
+                    #     # but let's see if we run into those cases first
+                    #     import pdb; pdb.set_trace()
+                    #     raise RuntimeError(
+                    #         "To commit files in direct mode, please first git "
+                    #         "or git-annex add them first!  Files: %s"
+                    #         % ', '.join(files_changed_notstaged)
+                    #     )
                     # Files which were staged but not among files
-                    staged_not_to_commit = all_staged_files.difference(files_set)
+                    staged_not_to_commit = changed_files[True].difference(files_set)
                     if staged_not_to_commit:
                         # Need an alternative index_file
                         with make_tempfile() as index_file: