add test_cmp function for test scripts

Many scripts compare actual and expected output using
"diff -u". This is nicer than "cmp" because the output shows
how the two differ. However, not all versions of diff
understand -u, leading to unnecessary test failure.

This adds a test_cmp function to the test scripts and
switches all "diff -u" invocations to use it. The function
uses the contents of "$GIT_TEST_CMP" to compare its
arguments; the default is "diff -u".

On systems with a less-capable diff, you can do:

  GIT_TEST_CMP=cmp make test

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 7 insertions, 7 deletions

diff --git a/t/t7502-commit.sh b/t/t7502-commit.sh
index b780fdd..284c941 100755
--- a/t/t7502-commit.sh
+++ b/t/t7502-commit.sh
@@ -85,7 +85,7 @@ test_expect_success 'verbose' '
 	git add negative &&
 	git status -v | sed -ne "/^diff --git /p" >actual &&
 	echo "diff --git a/negative b/negative" >expect &&
-	diff -u expect actual
+	test_cmp expect actual
 
 '
 
@@ -95,7 +95,7 @@ test_expect_success 'cleanup commit messages (verbatim,-t)' '
 	{ echo;echo "# text";echo; } >expect &&
 	git commit --cleanup=verbatim -t expect -a &&
 	git cat-file -p HEAD |sed -e "1,/^\$/d" |head -n 3 >actual &&
-	diff -u expect actual
+	test_cmp expect actual
 
 '
 
@@ -104,7 +104,7 @@ test_expect_success 'cleanup commit messages (verbatim,-F)' '
 	echo >>negative &&
 	git commit --cleanup=verbatim -F expect -a &&
 	git cat-file -p HEAD |sed -e "1,/^\$/d">actual &&
-	diff -u expect actual
+	test_cmp expect actual
 
 '
 
@@ -113,7 +113,7 @@ test_expect_success 'cleanup commit messages (verbatim,-m)' '
 	echo >>negative &&
 	git commit --cleanup=verbatim -m "$(cat expect)" -a &&
 	git cat-file -p HEAD |sed -e "1,/^\$/d">actual &&
-	diff -u expect actual
+	test_cmp expect actual
 
 '
 
@@ -124,7 +124,7 @@ test_expect_success 'cleanup commit messages (whitespace,-F)' '
 	echo "# text" >expect &&
 	git commit --cleanup=whitespace -F text -a &&
 	git cat-file -p HEAD |sed -e "1,/^\$/d">actual &&
-	diff -u expect actual
+	test_cmp expect actual
 
 '
 
@@ -135,7 +135,7 @@ test_expect_success 'cleanup commit messages (strip,-F)' '
 	echo sample >expect &&
 	git commit --cleanup=strip -F text -a &&
 	git cat-file -p HEAD |sed -e "1,/^\$/d">actual &&
-	diff -u expect actual
+	test_cmp expect actual
 
 '
 
@@ -150,7 +150,7 @@ test_expect_success 'cleanup commit messages (strip,-F,-e)' '
 	{ echo;echo sample;echo; } >text &&
 	git commit -e -F text -a &&
 	head -n 4 .git/COMMIT_EDITMSG >actual &&
-	diff -u expect actual
+	test_cmp expect actual
 
 '