Re: [PATCH] patch-id: fix scan_hunk_header on diffs with -U1
From: Junio C Hamano <hidden>
Date: 2022-01-26 05:13:31
Jerry Zhang [off-list ref] writes:
Normally diffs will contain a hunk header of the format "@@ -2,2 +2,15 @@ code". However when git diff is given "-U1" indicating that diffs are surrounded by only one line of context, it can omit the second comma separated value in either before or after line counts in the case where there is only one line.
Yes, it is possible that l and n in "@@ -k,l +m,n @@" is 1 in which case ",1" is omitted altogether. I however do not think it is limited to "-U1". The above description is inaccurate. $ echo one >foo $ git add foo $ echo two >foo $ git diff foo diff --git i/foo w/foo index 257cc5642c..5716ca5987 100644 --- i/foo +++ w/foo @@ -1 +1 @@ -one +two
Fix by explicitly setting line count to 1 when there is no comma, and add a test.
It is correct to assume missing ,l and ,n as 1. We should have the same logic in apply.c (I wonder if there is a way to share the parser, but I do not know if it is worth it).
quoted hunk
Signed-off-by: Jerry Zhang <redacted> --- builtin/patch-id.c | 9 +++++++-- t/t4204-patch-id.sh | 32 +++++++++++++++++++++++++++++++- 2 files changed, 38 insertions(+), 3 deletions(-)diff --git a/builtin/patch-id.c b/builtin/patch-id.c index 822ffff51f..881fcf3273 100644 --- a/builtin/patch-id.c +++ b/builtin/patch-id.c@@ -30,26 +30,31 @@ static int scan_hunk_header(const char *p, int *p_before, int *p_after) q = p + 4;
I wonder if the repeated code from here ...
n = strspn(q, digits);
if (q[n] == ',') {
q += n + 1;
+ *p_before = atoi(q);
n = strspn(q, digits);
+ } else {
+ *p_before = 1;
}
+... down to here ought to be in a helper function to parse l out of k[,l]. But that can and should be done as a post-fix cleanup.
quoted hunk
if (n == 0 || q[n] != ' ' || q[n+1] != '+') return 0; r = q + n + 2; n = strspn(r, digits); if (r[n] == ',') { r += n + 1; + *p_after = atoi(r); n = strspn(r, digits); + } else { + *p_after = 1; } if (n == 0) return 0; - *p_before = atoi(q); - *p_after = atoi(r); return 1; } static int get_one_patchid(struct object_id *next_oid, struct object_id *result, struct strbuf *line_buf, int stable)diff --git a/t/t4204-patch-id.sh b/t/t4204-patch-id.sh index 80f4a65b28..08d10dfc3e 100755 --- a/t/t4204-patch-id.sh +++ b/t/t4204-patch-id.sh@@ -36,11 +36,11 @@ test_expect_success 'patch-id output is well-formed' ' calc_patch_id () { patch_name="$1" shift git patch-id "$@" >patch-id.output && sed "s/ .*//" patch-id.output >patch-id_"$patch_name" && - test_line_count -gt 0 patch-id_"$patch_name" + test_line_count -eq 1 patch-id_"$patch_name" } get_top_diff () { git log -p -1 "$@" -O bar-then-foo -- }@@ -200,6 +200,36 @@ EOF test_expect_success 'patch-id handles no-nl-at-eof markers' ' cat nonl | calc_patch_id nonl && cat withnl | calc_patch_id withnl && test_cmp patch-id_nonl patch-id_withnl ' + +cat >diffu1 <<\EOF +diff --git a/bar b/bar +index bdaf90f..31051f6 100644 +--- a/bar ++++ b/bar +@@ -2 +2,2 @@ + b ++c +diff --git a/car b/car +index 00750ed..2ae5e34 100644 +--- a/car ++++ b/car +@@ -1 +1,2 @@ + 3 ++d +diff --git a/foo b/foo +index e439850..7146eb8 100644 +--- a/foo ++++ b/foo +@@ -2 +2,2 @@ + a ++e +EOF + +test_expect_success 'patch-id handles diffs with -U1' ' + cat diffu1 | calc_patch_id diffu1 && + test_config patchid.stable true && + cat diffu1 | calc_patch_id diffu1stable +' test_done