From 56fa5ac39a8601d965127abebbc533f29eaef751 Mon Sep 17 00:00:00 2001
From: Jerry Zhang <jerry@skydio.com>
Date: Tue, 1 Feb 2022 20:20:15 -0800
Subject: patch-id: fix antipatterns in tests

Clean up the tests for patch-id by moving file preparation
tasks inside the test body and redirecting files directly into
stdin instead of using 'cat'.

Signed-off-by: Jerry Zhang <jerry@skydio.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 t/t4204-patch-id.sh | 64 ++++++++++++++++++++++++++---------------------------
 1 file changed, 31 insertions(+), 33 deletions(-)

(limited to 't')

diff --git a/t/t4204-patch-id.sh b/t/t4204-patch-id.sh
index 80f4a65b28..2bc940a07e 100755
--- a/t/t4204-patch-id.sh
+++ b/t/t4204-patch-id.sh
@@ -166,40 +166,38 @@ test_expect_success 'patch-id respects config from subdir' '
 	)
 '
 
-cat >nonl <<\EOF
-diff --git i/a w/a
-index e69de29..2e65efe 100644
---- i/a
-+++ w/a
-@@ -0,0 +1 @@
-+a
-\ No newline at end of file
-diff --git i/b w/b
-index e69de29..6178079 100644
---- i/b
-+++ w/b
-@@ -0,0 +1 @@
-+b
-EOF
-
-cat >withnl <<\EOF
-diff --git i/a w/a
-index e69de29..7898192 100644
---- i/a
-+++ w/a
-@@ -0,0 +1 @@
-+a
-diff --git i/b w/b
-index e69de29..6178079 100644
---- i/b
-+++ w/b
-@@ -0,0 +1 @@
-+b
-EOF
-
 test_expect_success 'patch-id handles no-nl-at-eof markers' '
-	cat nonl | calc_patch_id nonl &&
-	cat withnl | calc_patch_id withnl &&
+	cat >nonl <<-\EOF &&
+	diff --git i/a w/a
+	index e69de29..2e65efe 100644
+	--- i/a
+	+++ w/a
+	@@ -0,0 +1 @@
+	+a
+	\ No newline at end of file
+	diff --git i/b w/b
+	index e69de29..6178079 100644
+	--- i/b
+	+++ w/b
+	@@ -0,0 +1 @@
+	+b
+	EOF
+	cat >withnl <<-\EOF &&
+	diff --git i/a w/a
+	index e69de29..7898192 100644
+	--- i/a
+	+++ w/a
+	@@ -0,0 +1 @@
+	+a
+	diff --git i/b w/b
+	index e69de29..6178079 100644
+	--- i/b
+	+++ w/b
+	@@ -0,0 +1 @@
+	+b
+	EOF
+	calc_patch_id nonl <nonl &&
+	calc_patch_id withnl <withnl &&
 	test_cmp patch-id_nonl patch-id_withnl
 '
 test_done
-- 
cgit v1.2.3


From 757e75c81e4332e363b90a0534a657b1bb6546fa Mon Sep 17 00:00:00 2001
From: Jerry Zhang <jerry@skydio.com>
Date: Tue, 1 Feb 2022 20:19:45 -0800
Subject: patch-id: fix scan_hunk_header on diffs with 1 line of before/after

Normally diffs will contain a hunk header of the format
"@@ -2,2 +2,15 @@ code". However when there is only 1 line of
change, the unified diff format allows for the second comma
separated value to be omitted in either before or after
line counts.

This can produce hunk headers that look like
"@@ -2 +2,18 @@ code" or "@@ -2,2 +2 @@ code".
As a result, scan_hunk_header mistakenly returns the line
number as line count, which then results in unpredictable
parsing errors with the rest of the patch, including giving
multiple lines of output for a single commit.

Fix by explicitly setting line count to 1 when there is
no comma, and add a test.

apply.c contains this same logic except it is correct. A
worthwhile future project might be to unify these two diff
parsers so they both benefit from fixes.

Signed-off-by: Jerry Zhang <jerry@skydio.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 t/t4204-patch-id.sh | 31 ++++++++++++++++++++++++++++++-
 1 file changed, 30 insertions(+), 1 deletion(-)

(limited to 't')

diff --git a/t/t4204-patch-id.sh b/t/t4204-patch-id.sh
index 2bc940a07e..a730c0db98 100755
--- a/t/t4204-patch-id.sh
+++ b/t/t4204-patch-id.sh
@@ -38,7 +38,7 @@ calc_patch_id () {
 	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 () {
@@ -200,4 +200,33 @@ test_expect_success 'patch-id handles no-nl-at-eof markers' '
 	calc_patch_id withnl <withnl &&
 	test_cmp patch-id_nonl patch-id_withnl
 '
+
+test_expect_success 'patch-id handles diffs with one line of before/after' '
+	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
+	calc_patch_id diffu1 <diffu1 &&
+	test_config patchid.stable true &&
+	calc_patch_id diffu1stable <diffu1
+'
 test_done
-- 
cgit v1.2.3