t4215: use helper function to check output

When git commands are placed in the upstream of a pipe, their return
codes are lost. In this particular case, it is especially bad since we
are testing the intricacies of `git log --graph` behavior and if we hit
an unexpected failure or segfault, we want to know this.

Extract the common output checking logic into check_graph() where we
redirect the output of git commands upstream of pipe into a file and
have sed read from that file so that git failures are detected.

This patch is best viewed with `--color-moved`.

Signed-off-by: Denton Liu <liu.denton@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 97 insertions, 111 deletions

diff --git a/t/t4215-log-skewed-merges.sh b/t/t4215-log-skewed-merges.sh
index d33c6438d8..18709a723e 100755
--- a/t/t4215-log-skewed-merges.sh
+++ b/t/t4215-log-skewed-merges.sh
@@ -4,8 +4,25 @@ test_description='git log --graph of skewed merges'
 
 . ./test-lib.sh
 
+check_graph () {
+	cat >expect &&
+	git log --graph --pretty=tformat:%s "$@" >actual.raw &&
+	sed "s/ *$//" actual.raw >actual &&
+	test_cmp expect actual
+}
+
 test_expect_success 'log --graph with merge fusing with its left and right neighbors' '
-	cat >expect <<-\EOF &&
+	git checkout --orphan _p &&
+	test_commit A &&
+	test_commit B &&
+	git checkout -b _q @^ && test_commit C &&
+	git checkout -b _r @^ && test_commit D &&
+	git checkout _p && git merge --no-ff _q _r -m E &&
+	git checkout _r && test_commit F &&
+	git checkout _p && git merge --no-ff _r -m G &&
+	git checkout @^^ && git merge --no-ff _p -m H &&
+
+	check_graph <<-\EOF
 	*   H
 	|\
 	| *   G
@@ -20,23 +37,20 @@ test_expect_success 'log --graph with merge fusing with its left and right neigh
 	|/
 	* A
 	EOF
-
-	git checkout --orphan _p &&
-	test_commit A &&
-	test_commit B &&
-	git checkout -b _q @^ && test_commit C &&
-	git checkout -b _r @^ && test_commit D &&
-	git checkout _p && git merge --no-ff _q _r -m E &&
-	git checkout _r && test_commit F &&
-	git checkout _p && git merge --no-ff _r -m G &&
-	git checkout @^^ && git merge --no-ff _p -m H &&
-
-	git log --graph --pretty=tformat:%s | sed "s/ *$//" >actual &&
-	test_cmp expect actual
 '
 
 test_expect_success 'log --graph with left-skewed merge' '
-	cat >expect <<-\EOF &&
+	git checkout --orphan 0_p && test_commit 0_A &&
+	git checkout -b 0_q 0_p && test_commit 0_B &&
+	git checkout -b 0_r 0_p &&
+	test_commit 0_C &&
+	test_commit 0_D &&
+	git checkout -b 0_s 0_p && test_commit 0_E &&
+	git checkout -b 0_t 0_p && git merge --no-ff 0_r^ 0_s -m 0_F &&
+	git checkout 0_p && git merge --no-ff 0_s -m 0_G &&
+	git checkout @^ && git merge --no-ff 0_q 0_r 0_t 0_p -m 0_H &&
+
+	check_graph <<-\EOF
 	*-----.   0_H
 	|\ \ \ \
 	| | | | * 0_G
@@ -57,23 +71,20 @@ test_expect_success 'log --graph with left-skewed merge' '
 	|/
 	* 0_A
 	EOF
-
-	git checkout --orphan 0_p && test_commit 0_A &&
-	git checkout -b 0_q 0_p && test_commit 0_B &&
-	git checkout -b 0_r 0_p &&
-	test_commit 0_C &&
-	test_commit 0_D &&
-	git checkout -b 0_s 0_p && test_commit 0_E &&
-	git checkout -b 0_t 0_p && git merge --no-ff 0_r^ 0_s -m 0_F &&
-	git checkout 0_p && git merge --no-ff 0_s -m 0_G &&
-	git checkout @^ && git merge --no-ff 0_q 0_r 0_t 0_p -m 0_H &&
-
-	git log --graph --pretty=tformat:%s | sed "s/ *$//" >actual &&
-	test_cmp expect actual
 '
 
 test_expect_success 'log --graph with nested left-skewed merge' '
-	cat >expect <<-\EOF &&
+	git checkout --orphan 1_p &&
+	test_commit 1_A &&
+	test_commit 1_B &&
+	test_commit 1_C &&
+	git checkout -b 1_q @^ && test_commit 1_D &&
+	git checkout 1_p && git merge --no-ff 1_q -m 1_E &&
+	git checkout -b 1_r @~3 && test_commit 1_F &&
+	git checkout 1_p && git merge --no-ff 1_r -m 1_G &&
+	git checkout @^^ && git merge --no-ff 1_p -m 1_H &&
+
+	check_graph <<-\EOF
 	*   1_H
 	|\
 	| *   1_G
@@ -88,23 +99,24 @@ test_expect_success 'log --graph with nested left-skewed merge' '
 	|/
 	* 1_A
 	EOF
-
-	git checkout --orphan 1_p &&
-	test_commit 1_A &&
-	test_commit 1_B &&
-	test_commit 1_C &&
-	git checkout -b 1_q @^ && test_commit 1_D &&
-	git checkout 1_p && git merge --no-ff 1_q -m 1_E &&
-	git checkout -b 1_r @~3 && test_commit 1_F &&
-	git checkout 1_p && git merge --no-ff 1_r -m 1_G &&
-	git checkout @^^ && git merge --no-ff 1_p -m 1_H &&
-
-	git log --graph --pretty=tformat:%s | sed "s/ *$//" >actual &&
-	test_cmp expect actual
 '
 
 test_expect_success 'log --graph with nested left-skewed merge following normal merge' '
-	cat >expect <<-\EOF &&
+	git checkout --orphan 2_p &&
+	test_commit 2_A &&
+	test_commit 2_B &&
+	test_commit 2_C &&
+	git checkout -b 2_q @^^ &&
+	test_commit 2_D &&
+	test_commit 2_E &&
+	git checkout -b 2_r @^ && test_commit 2_F &&
+	git checkout 2_q &&
+	git merge --no-ff 2_r -m 2_G &&
+	git merge --no-ff 2_p^ -m 2_H &&
+	git checkout -b 2_s @^^ && git merge --no-ff 2_q -m 2_J &&
+	git checkout 2_p && git merge --no-ff 2_s -m 2_K &&
+
+	check_graph <<-\EOF
 	*   2_K
 	|\
 	| *   2_J
@@ -124,27 +136,23 @@ test_expect_success 'log --graph with nested left-skewed merge following normal
 	|/
 	* 2_A
 	EOF
-
-	git checkout --orphan 2_p &&
-	test_commit 2_A &&
-	test_commit 2_B &&
-	test_commit 2_C &&
-	git checkout -b 2_q @^^ &&
-	test_commit 2_D &&
-	test_commit 2_E &&
-	git checkout -b 2_r @^ && test_commit 2_F &&
-	git checkout 2_q &&
-	git merge --no-ff 2_r -m 2_G &&
-	git merge --no-ff 2_p^ -m 2_H &&
-	git checkout -b 2_s @^^ && git merge --no-ff 2_q -m 2_J &&
-	git checkout 2_p && git merge --no-ff 2_s -m 2_K &&
-
-	git log --graph --pretty=tformat:%s | sed "s/ *$//" >actual &&
-	test_cmp expect actual
 '
 
 test_expect_success 'log --graph with nested right-skewed merge following left-skewed merge' '
-	cat >expect <<-\EOF &&
+	git checkout --orphan 3_p &&
+	test_commit 3_A &&
+	git checkout -b 3_q &&
+	test_commit 3_B &&
+	test_commit 3_C &&
+	git checkout -b 3_r @^ &&
+	test_commit 3_D &&
+	git checkout 3_q && git merge --no-ff 3_r -m 3_E &&
+	git checkout 3_p && git merge --no-ff 3_q -m 3_F &&
+	git checkout 3_r && test_commit 3_G &&
+	git checkout 3_p && git merge --no-ff 3_r -m 3_H &&
+	git checkout @^^ && git merge --no-ff 3_p -m 3_J &&
+
+	check_graph <<-\EOF
 	*   3_J
 	|\
 	| *   3_H
@@ -161,26 +169,21 @@ test_expect_success 'log --graph with nested right-skewed merge following left-s
 	|/
 	* 3_A
 	EOF
-
-	git checkout --orphan 3_p &&
-	test_commit 3_A &&
-	git checkout -b 3_q &&
-	test_commit 3_B &&
-	test_commit 3_C &&
-	git checkout -b 3_r @^ &&
-	test_commit 3_D &&
-	git checkout 3_q && git merge --no-ff 3_r -m 3_E &&
-	git checkout 3_p && git merge --no-ff 3_q -m 3_F &&
-	git checkout 3_r && test_commit 3_G &&
-	git checkout 3_p && git merge --no-ff 3_r -m 3_H &&
-	git checkout @^^ && git merge --no-ff 3_p -m 3_J &&
-
-	git log --graph --pretty=tformat:%s | sed "s/ *$//" >actual &&
-	test_cmp expect actual
 '
 
 test_expect_success 'log --graph with right-skewed merge following a left-skewed one' '
-	cat >expect <<-\EOF &&
+	git checkout --orphan 4_p &&
+	test_commit 4_A &&
+	test_commit 4_B &&
+	test_commit 4_C &&
+	git checkout -b 4_q @^^ && test_commit 4_D &&
+	git checkout -b 4_r 4_p^ && git merge --no-ff 4_q -m 4_E &&
+	git checkout -b 4_s 4_p^^ &&
+	git merge --no-ff 4_r -m 4_F &&
+	git merge --no-ff 4_p -m 4_G &&
+	git checkout @^^ && git merge --no-ff 4_s -m 4_H &&
+
+	check_graph --date-order <<-\EOF
 	*   4_H
 	|\
 	| *   4_G
@@ -198,24 +201,25 @@ test_expect_success 'log --graph with right-skewed merge following a left-skewed
 	|/
 	* 4_A
 	EOF
-
-	git checkout --orphan 4_p &&
-	test_commit 4_A &&
-	test_commit 4_B &&
-	test_commit 4_C &&
-	git checkout -b 4_q @^^ && test_commit 4_D &&
-	git checkout -b 4_r 4_p^ && git merge --no-ff 4_q -m 4_E &&
-	git checkout -b 4_s 4_p^^ &&
-	git merge --no-ff 4_r -m 4_F &&
-	git merge --no-ff 4_p -m 4_G &&
-	git checkout @^^ && git merge --no-ff 4_s -m 4_H &&
-
-	git log --graph --date-order --pretty=tformat:%s | sed "s/ *$//" >actual &&
-	test_cmp expect actual
 '
 
 test_expect_success 'log --graph with octopus merge with column joining its penultimate parent' '
-	cat >expect <<-\EOF &&
+	git checkout --orphan 5_p &&
+	test_commit 5_A &&
+	git branch 5_q &&
+	git branch 5_r &&
+	test_commit 5_B &&
+	git checkout 5_q && test_commit 5_C &&
+	git checkout 5_r && test_commit 5_D &&
+	git checkout 5_p &&
+	git merge --no-ff 5_q 5_r -m 5_E &&
+	git checkout 5_q && test_commit 5_F &&
+	git checkout -b 5_s 5_p^ &&
+	git merge --no-ff 5_p 5_q -m 5_G &&
+	git checkout 5_r &&
+	git merge --no-ff 5_s -m 5_H &&
+
+	check_graph <<-\EOF
 	*   5_H
 	|\
 	| *-.   5_G
@@ -234,24 +238,6 @@ test_expect_success 'log --graph with octopus merge with column joining its penu
 	|/
 	* 5_A
 	EOF
-
-	git checkout --orphan 5_p &&
-	test_commit 5_A &&
-	git branch 5_q &&
-	git branch 5_r &&
-	test_commit 5_B &&
-	git checkout 5_q && test_commit 5_C &&
-	git checkout 5_r && test_commit 5_D &&
-	git checkout 5_p &&
-	git merge --no-ff 5_q 5_r -m 5_E &&
-	git checkout 5_q && test_commit 5_F &&
-	git checkout -b 5_s 5_p^ &&
-	git merge --no-ff 5_p 5_q -m 5_G &&
-	git checkout 5_r &&
-	git merge --no-ff 5_s -m 5_H &&
-
-	git log --graph --pretty=tformat:%s | sed "s/ *$//" >actual &&
-	test_cmp expect actual
 '
 
 test_done