From a5229cc95103fab9449bf198a8a119482a8f0845 Mon Sep 17 00:00:00 2001 From: Johannes Schindelin Date: Sat, 9 Jul 2016 09:23:50 +0200 Subject: diff: demonstrate a bug with --patience and --ignore-space-at-eol When a single character is added to a line, the combination of these two options results in an empty diff. This bug was noticed and reported by Naja Melan. Signed-off-by: Johannes Schindelin Signed-off-by: Junio C Hamano --- t/t4033-diff-patience.sh | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 't') diff --git a/t/t4033-diff-patience.sh b/t/t4033-diff-patience.sh index 3c9932edf3..5f0d0b164c 100755 --- a/t/t4033-diff-patience.sh +++ b/t/t4033-diff-patience.sh @@ -5,6 +5,14 @@ test_description='patience diff algorithm' . ./test-lib.sh . "$TEST_DIRECTORY"/lib-diff-alternative.sh +test_expect_failure '--ignore-space-at-eol with a single appended character' ' + printf "a\nb\nc\n" >pre && + printf "a\nbX\nc\n" >post && + test_must_fail git diff --no-index \ + --patience --ignore-space-at-eol pre post >diff && + grep "^+.*X" diff +' + test_diff_frobnitz "patience" test_diff_unique "patience" -- cgit v1.2.3 From 044fb190f75cdec35e56bde30ec214ab144311d9 Mon Sep 17 00:00:00 2001 From: Johannes Schindelin Date: Sat, 9 Jul 2016 09:23:55 +0200 Subject: diff: fix a double off-by-one with --ignore-space-at-eol When comparing two lines, ignoring any whitespace at the end, we first try to match as many bytes as possible and break out of the loop only upon mismatch, to let the remainder be handled by the code shared with the other whitespace-ignoring code paths. When comparing the bytes, however, we incremented the counters always, even if the bytes did not match. And because we fall through to the space-at-eol handling at that point, it is as if that mismatch never happened. Signed-off-by: Johannes Schindelin Signed-off-by: Junio C Hamano --- t/t4033-diff-patience.sh | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 't') diff --git a/t/t4033-diff-patience.sh b/t/t4033-diff-patience.sh index 5f0d0b164c..113304dc59 100755 --- a/t/t4033-diff-patience.sh +++ b/t/t4033-diff-patience.sh @@ -5,7 +5,7 @@ test_description='patience diff algorithm' . ./test-lib.sh . "$TEST_DIRECTORY"/lib-diff-alternative.sh -test_expect_failure '--ignore-space-at-eol with a single appended character' ' +test_expect_success '--ignore-space-at-eol with a single appended character' ' printf "a\nb\nc\n" >pre && printf "a\nbX\nc\n" >post && test_must_fail git diff --no-index \ -- cgit v1.2.3