refactor get_textconv to not require diff_filespec

This function actually does two things:

  1. Load the userdiff driver for the filespec.

  2. Decide whether the driver has a textconv component, and
     initialize the textconv cache if applicable.

Only part (1) requires the filespec object, and some callers
may not have a filespec at all. So let's split them it into
two functions, and put part (2) with the userdiff code,
which is a better fit.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 1 insertions, 13 deletions

diff --git a/diff.c b/diff.c
index ba5f7aa217..3f538f5803 100644
--- a/diff.c
+++ b/diff.c
@@ -1976,19 +1976,7 @@ struct userdiff_driver *get_textconv(struct diff_filespec *one)
 		return NULL;
 
 	diff_filespec_load_driver(one);
-	if (!one->driver->textconv)
-		return NULL;
-
-	if (one->driver->textconv_want_cache && !one->driver->textconv_cache) {
-		struct notes_cache *c = xmalloc(sizeof(*c));
-		struct strbuf name = STRBUF_INIT;
-
-		strbuf_addf(&name, "textconv/%s", one->driver->name);
-		notes_cache_init(c, name.buf, one->driver->textconv);
-		one->driver->textconv_cache = c;
-	}
-
-	return one->driver;
+	return userdiff_get_textconv(one->driver);
 }
 
 static void builtin_diff(const char *name_a,