Re: [PATCH] patch-id: fix scan_hunk_header on diffs with -U1
- From
Junio C Hamano <gitster@pobox.com>
- Date
- Jan 26, 2022, 05:13 UTC
- Message-ID
- <xmqqtudrt6yy.fsf@gitster.g>
- In-Reply-To
- <20220125221602.26557-1-jerry@skydio.com>
Jerry Zhang <jerry@skydio.com> writes:
Show 6 quoted lines
> 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).
Show 13 quoted lines
> Signed-off-by: Jerry Zhang <jerry@skydio.com> > --- > 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 ...
Show 9 quoted lines
> 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.
Show 76 quoted lines
> 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