Subject: Re: [PATCH v2 0/3] Unify trailers formatting logic for pretty.c and ref-filter.c

From: Junio C Hamano <[email-masked]>
Date: Sat, 30 Jan 2021 12:20:56 -0800

Junio C Hamano <[email-masked]> writes:

> With this queued directly on top of master, I am getting these
> failures.
>
> t6300-for-each-ref.sh                            (Wstat: 256 Tests: 301 Failed: 6)
>   Failed tests:  277-280, 285, 287
>   Non-zero exit status: 1

Judging from the way the first failure happens, it appears that
some code depends on a kind of shell portability issues?

The failure is under GNU bash, version 5.1.4(1)-release (x86_64-pc-linux-gnu)

Ah, I think I know what is going on.

test_trailer_option() {
	title="$1"
	option="$2"
	expect="$3"
	test_expect_success "$title" '
		echo $expect >expect &&
		git for-each-ref --format="%($option)" refs/heads/main >actual &&
		test_cmp expect actual &&
		git for-each-ref --format="%(contents:$option)" refs/heads/main >actual &&
		test_cmp expect actual
	'
}

Not quoting "$expect" given to 'echo' inside double-quote is
criminal, but I do not think that contributes to this particular
failure.  The problem is in the callers.

test_trailer_option '%(trailers:key=foo) shows that trailer' \
	'trailers:key=Signed-off-by' 'Signed-off-by: A U Thor <[email-masked]>\n'

Doing

	expect='foo\n'
	echo $expect

and expecting that somebody would magically turn \n to a true
newline is the bug.  Not everybody's builtin "echo" works that way.

Here is a quick fix-up.  I didn't check which parts are to be blamed
on which patch of yours, if any, so you might need to split them up
into multiple pieces (i.e. a preliminary clean-up patch, and a patch
each to be applied to part N/3 (1 <= N <= 3) of your patch).

 t/t6300-for-each-ref.sh | 22 +++++++++++++++-------
 1 file changed, 15 insertions(+), 7 deletions(-)

diff --git c/t/t6300-for-each-ref.sh w/t/t6300-for-each-ref.sh
index a8835b1391..0278cb9924 100755
--- c/t/t6300-for-each-ref.sh
+++ w/t/t6300-for-each-ref.sh
@@ -874,7 +874,7 @@ test_trailer_option() {
 	option="$2"
 	expect="$3"
 	test_expect_success "$title" '
-		echo $expect >expect &&
+		echo "$expect" >expect &&
 		git for-each-ref --format="%($option)" refs/heads/main >actual &&
 		test_cmp expect actual &&
 		git for-each-ref --format="%(contents:$option)" refs/heads/main >actual &&
@@ -883,13 +883,18 @@ test_trailer_option() {
 }
 
 test_trailer_option '%(trailers:key=foo) shows that trailer' \
-	'trailers:key=Signed-off-by' 'Signed-off-by: A U Thor <[email-masked]>\n'
+	'trailers:key=Signed-off-by' 'Signed-off-by: A U Thor <[email-masked]>
+'
 test_trailer_option '%(trailers:key=foo) is case insensitive' \
-	'trailers:key=SiGned-oFf-bY' 'Signed-off-by: A U Thor <[email-masked]>\n'
+	'trailers:key=SiGned-oFf-bY' 'Signed-off-by: A U Thor <[email-masked]>
+'
 test_trailer_option '%(trailers:key=foo:) trailing colon also works' \
-	'trailers:key=Signed-off-by:' 'Signed-off-by: A U Thor <[email-masked]>\n'
+	'trailers:key=Signed-off-by:' 'Signed-off-by: A U Thor <[email-masked]>
+'
 test_trailer_option '%(trailers:key=foo) multiple keys' \
-	'trailers:key=Reviewed-by:,key=Signed-off-by' 'Reviewed-by: A U Thor <[email-masked]>\nSigned-off-by: A U Thor <[email-masked]>\n'
+	'trailers:key=Reviewed-by:,key=Signed-off-by' 'Reviewed-by: A U Thor <[email-masked]>
+Signed-off-by: A U Thor <[email-masked]>
+'
 test_trailer_option '%(trailers:key=nonexistent) becomes empty' \
 	'trailers:key=Shined-off-by:' ''
 
@@ -928,11 +933,14 @@ test_expect_success 'pretty format %(trailers:key=foo,only=no) also includes non
 '
 
 test_trailer_option '%(trailers:key=foo,valueonly) shows only value' \
-	'trailers:key=Signed-off-by,valueonly' 'A U Thor <[email-masked]>\n'
+	'trailers:key=Signed-off-by,valueonly' 'A U Thor <[email-masked]>
+'
 test_trailer_option '%(trailers:separator) changes separator' \
 	'trailers:separator=%x2C,key=Reviewed-by,key=Signed-off-by:' 'Reviewed-by: A U Thor <[email-masked]>,Signed-off-by: A U Thor <[email-masked]>'
 test_trailer_option '%(trailers:key_value_separator) changes key-value separator' \
-	'trailers:key_value_separator=%x2C,key=Reviewed-by,key=Signed-off-by:' 'Reviewed-by,A U Thor <[email-masked]>\nSigned-off-by,A U Thor <[email-masked]>\n'
+	'trailers:key_value_separator=%x2C,key=Reviewed-by,key=Signed-off-by:' 'Reviewed-by,A U Thor <[email-masked]>
+Signed-off-by,A U Thor <[email-masked]>
+'
 test_trailer_option '%(trailers:separator,key_value_separator) changes both separators' \
 	'trailers:separator=%x2C,key_value_separator=%x2C,key=Reviewed-by,key=Signed-off-by:' 'Reviewed-by,A U Thor <[email-masked]>,Signed-off-by,A U Thor <[email-masked]>'