[BUG] git log -S not respecting --no-textconv

Hi,

It seems the command "git log --no-textconv -Sfoo" still runs the
textconv filter (noticed because I have a broken textconv filter that
lets "git log -S" error out).

Steps to reproduce:

Create a repo with *.txt file(s) in it
$ echo '*.txt diff=wrong' > .gitattributes

An incorrect textconv filter errors out as expected:

$ git -c diff.wrong.textconv='xxx' log -Sfoo 
error: cannot run xxx: No such file or directory
fatal: unable to read files to diff

but --no-textconv has no effect:

$ git -c diff.wrong.textconv='xxx' log --no-textconv -Sfoo
error: cannot run xxx: No such file or directory
fatal: unable to read files to diff

-- 
Matthieu Moy
http://www-verimag.imag.fr/~moy/

git log -S doesn't respect --no-textconv:

    $ echo '*.txt diff=wrong' > .gitattributes
    $ git -c diff.wrong.textconv='xxx' log --no-textconv -Sfoo
    error: cannot run xxx: No such file or directory
    fatal: unable to read files to diff

Signed-off-by: Simon Ruderich <redacted>
Reported-by: Matthieu Moy <redacted>
---
On Thu, Apr 04, 2013 at 10:34:17AM +0200, Matthieu Moy wrote:

Hi,

It seems the command "git log --no-textconv -Sfoo" still runs the
textconv filter (noticed because I have a broken textconv filter that
lets "git log -S" error out).

[snip]

Hello Matthieu,

This patch should fix it. All tests pass.

Regards
Simon

 diffcore-pickaxe.c     | 15 ++++++++++++---
 t/t4209-log-pickaxe.sh | 14 ++++++++++++++
 2 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/diffcore-pickaxe.c b/diffcore-pickaxe.c
index b097fa7..f814a52 100644
--- a/diffcore-pickaxe.c
+++ b/diffcore-pickaxe.c

@@ -78,7 +78,6 @@ static void fill_one(struct diff_filespec *one,
 		     mmfile_t *mf, struct userdiff_driver **textconv)
 {
 	if (DIFF_FILE_VALID(one)) {
-		*textconv = get_textconv(one);
 		mf->size = fill_textconv(*textconv, one, &mf->ptr);
 	} else {
 		memset(mf, 0, sizeof(*mf));

@@ -97,6 +96,11 @@ static int diff_grep(struct diff_filepair *p, struct diff_options *o,
 	if (diff_unmodified_pair(p))
 		return 0;
 
+	if (DIFF_OPT_TST(o, ALLOW_TEXTCONV)) {
+		textconv_one = get_textconv(p->one);
+		textconv_two = get_textconv(p->two);
+	}
+
 	fill_one(p->one, &mf1, &textconv_one);
 	fill_one(p->two, &mf2, &textconv_two);
 

@@ -201,14 +205,19 @@ static unsigned int contains(mmfile_t *mf, struct diff_options *o,
 static int has_changes(struct diff_filepair *p, struct diff_options *o,
 		       regex_t *regexp, kwset_t kws)
 {
-	struct userdiff_driver *textconv_one = get_textconv(p->one);
-	struct userdiff_driver *textconv_two = get_textconv(p->two);
+	struct userdiff_driver *textconv_one = NULL;
+	struct userdiff_driver *textconv_two = NULL;
 	mmfile_t mf1, mf2;
 	int ret;
 
 	if (!o->pickaxe[0])
 		return 0;
 
+	if (DIFF_OPT_TST(o, ALLOW_TEXTCONV)) {
+		textconv_one = get_textconv(p->one);
+		textconv_two = get_textconv(p->two);
+	}
+
 	/*
 	 * If we have an unmodified pair, we know that the count will be the
 	 * same and don't even have to load the blobs. Unless textconv is in

diff --git a/t/t4209-log-pickaxe.sh b/t/t4209-log-pickaxe.sh
index eed7273..953cec8 100755
--- a/t/t4209-log-pickaxe.sh
+++ b/t/t4209-log-pickaxe.sh

@@ -116,4 +116,18 @@ test_expect_success 'log -S -i (nomatch)' '
 	test_cmp expect actual
 '
 
+test_expect_success 'log -S --textconv (missing textconv tool)' '
+	echo "* diff=test" >.gitattributes &&
+	test_must_fail git -c diff.test.textconv=missing log -Sfoo &&
+	rm .gitattributes
+'
+
+test_expect_success 'log -S --no-textconv (missing textconv tool)' '
+	echo "* diff=test" >.gitattributes &&
+	git -c diff.test.textconv=missing log -Sfoo --no-textconv >actual &&
+	>expect &&
+	test_cmp expect actual &&
+	rm .gitattributes
+'
+
 test_done

-- 
1.8.2

-- 
+ privacy is necessary
+ using gnupg http://gnupg.org
+ public key id: 0x92FEFDB7E44C32F9

On Thu, Apr 04, 2013 at 06:03:59PM +0200, Simon Ruderich wrote:

git log -S doesn't respect --no-textconv:

    $ echo '*.txt diff=wrong' > .gitattributes
    $ git -c diff.wrong.textconv='xxx' log --no-textconv -Sfoo
    error: cannot run xxx: No such file or directory
    fatal: unable to read files to diff

Signed-off-by: Simon Ruderich <redacted>
Reported-by: Matthieu Moy <redacted>

Usually these pseudo-headers are meant to be chronological, so you would
swap the order.

quoted

It seems the command "git log --no-textconv -Sfoo" still runs the
textconv filter (noticed because I have a broken textconv filter that
lets "git log -S" error out).

[snip]

Hello Matthieu,

This patch should fix it. All tests pass.

Thanks, the patch looks correct to me, although...

Dropping this is the right thing to do with the rest of your patch, but
like Matthieu, it took me a second to see why. Something like this
should probably go into the commit message:

  We need to check that the ALLOW_TEXTCONV diff option is set before
  loading the textconv drivers. Rather than pass the diff options
  structure into the fill_one helper, let's just determine the textconv
  driver outside of that function and pass that in.

Though I really think that justification would make more sense if your
second cleanup patch came first, pulling the get_textconv calls back out
to the callers (which is easy to justify, since one of the callers
already has to load them itself _anyway_, which is just ugly).

-Peff