reset: don't allow "git reset -- $pathspec" in bare repo

Running e.g. "git reset ." in a bare repo results in an index file
being created from the HEAD commit. The differences compared to the
index are then printed as usual, but since there is no worktree, it
will appear as if all files are deleted. For example, in a bare clone
of git.git:

  Unstaged changes after reset:
  D       .gitattributes
  D       .gitignore
  D       .mailmap
  ...

This happens because the check for is_bare_repository() happens after
we branch off into read_from_tree() to reset with paths. Fix by moving
the branching point after the check.

Signed-off-by: Martin von Zweigbergk <martinvonz@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/reset.c

@@ -295,8 +295,6 @@ int cmd_reset(int argc, const char **argv, const char *prefix)
 		else if (reset_type != NONE)
 			die(_("Cannot do %s reset with paths."),
 					_(reset_type_names[reset_type]));
-		return read_from_tree(pathspec, sha1,
-				quiet ? REFRESH_QUIET : REFRESH_IN_PORCELAIN);
 	}
 	if (reset_type == NONE)
 		reset_type = MIXED; /* by default */
@@ -308,6 +306,10 @@ int cmd_reset(int argc, const char **argv, const char *prefix)
 		die(_("%s reset is not allowed in a bare repository"),
 		    _(reset_type_names[reset_type]));
 
+	if (pathspec)
+		return read_from_tree(pathspec, sha1,
+				quiet ? REFRESH_QUIET : REFRESH_IN_PORCELAIN);
+
 	/* Soft reset does not touch the index file nor the working tree
 	 * at all, but requires them in a good order.  Other resets reset
 	 * the index file to the tree object we are switching to. */