Merge branch 'jk/log-follow-with-non-literal-pathspec'

"git [-c log.follow=true] log [--follow] ':(glob)f**'" used to barf.

* jk/log-follow-with-non-literal-pathspec:
  diff: detect pathspec magic not supported by --follow
  diff: factor out --follow pathspec check
  pathspec: factor out magic-to-name function

1 files changed, 27 insertions, 2 deletions

diff --git a/diff.c b/diff.c
index 1cdac6e..c106f8a 100644
--- a/diff.c
+++ b/diff.c
@@ -4751,6 +4751,31 @@ unsigned diff_filter_bit(char status)
 	return filter_bit[(int) status];
 }
 
+int diff_check_follow_pathspec(struct pathspec *ps, int die_on_error)
+{
+	unsigned forbidden_magic;
+
+	if (ps->nr != 1) {
+		if (die_on_error)
+			die(_("--follow requires exactly one pathspec"));
+		return 0;
+	}
+
+	forbidden_magic = ps->items[0].magic & ~(PATHSPEC_FROMTOP |
+						 PATHSPEC_LITERAL);
+	if (forbidden_magic) {
+		if (die_on_error) {
+			struct strbuf sb = STRBUF_INIT;
+			pathspec_magic_names(forbidden_magic, &sb);
+			die(_("pathspec magic not supported by --follow: %s"),
+			    sb.buf);
+		}
+		return 0;
+	}
+
+	return 1;
+}
+
 void diff_setup_done(struct diff_options *options)
 {
 	unsigned check_mask = DIFF_FORMAT_NAME |
@@ -4858,8 +4883,8 @@ void diff_setup_done(struct diff_options *options)
 
 	options->diff_path_counter = 0;
 
-	if (options->flags.follow_renames && options->pathspec.nr != 1)
-		die(_("--follow requires exactly one pathspec"));
+	if (options->flags.follow_renames)
+		diff_check_follow_pathspec(&options->pathspec, 1);
 
 	if (!options->use_color || external_diff())
 		options->color_moved = 0;