[PATCH v2] t4027,4041: Use test -s to test for an empty file

[Brian Gernhardt <brian@gernhardtsoftware.com>]

The tests had used a mixture of 'echo -n' (which is non-portable) and
either test_cmp or diff to check if a file is empty.  The much easier
and portable method to check for an empty file is '! test -s'

Signed-off-by: Brian Gernhardt <brian@gernhardtsoftware.com>
---

 Johannes Sixt wrote:
 > Shouldn't you replace these by
 >
 >	! test -s actual2 &&

 Yes, you're right.  I was just trying to get the tests to run and didn't really pay attention to what it was trying to do.

 t/t4027-diff-submodule.sh        |   10 +++++-----
 t/t4041-diff-submodule-option.sh |   14 +++++++-------
 2 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/t/t4027-diff-submodule.sh b/t/t4027-diff-submodule.sh
index 559b41e..8f016aa 100755
--- a/t/t4027-diff-submodule.sh
+++ b/t/t4027-diff-submodule.sh
@@ -105,13 +105,13 @@ test_expect_success 'git diff HEAD with dirty submodule (work tree, refs match)'
 	expect_from_to >expect.body $subprev $subprev-dirty &&
 	test_cmp expect.body actual.body &&
 	git diff --ignore-submodules HEAD >actual2 &&
-	echo -n "" | test_cmp - actual2 &&
+	! test -s actual2 &&
 	git diff --ignore-submodules=untracked HEAD >actual3 &&
 	sed -e "1,/^@@/d" actual3 >actual3.body &&
 	expect_from_to >expect.body $subprev $subprev-dirty &&
 	test_cmp expect.body actual3.body &&
 	git diff --ignore-submodules=dirty HEAD >actual4 &&
-	echo -n "" | test_cmp - actual4
+	! test -s actual4
 '
 test_done
 test_expect_success 'git diff HEAD with dirty submodule (index, refs match)' '
@@ -139,11 +139,11 @@ test_expect_success 'git diff HEAD with dirty submodule (untracked, refs match)'
 	expect_from_to >expect.body $subprev $subprev-dirty &&
 	test_cmp expect.body actual.body &&
 	git diff --ignore-submodules=all HEAD >actual2 &&
-	echo -n "" | test_cmp - actual2 &&
+	! test -s actual2 &&
 	git diff --ignore-submodules=untracked HEAD >actual3 &&
-	echo -n "" | test_cmp - actual3 &&
+	! test -s actual3 &&
 	git diff --ignore-submodules=dirty HEAD >actual4 &&
-	echo -n "" | test_cmp - actual4
+	! test -s actual4
 '
 
 test_expect_success 'git diff (empty submodule dir)' '
diff --git a/t/t4041-diff-submodule-option.sh b/t/t4041-diff-submodule-option.sh
index f44b906..db9b64d 100755
--- a/t/t4041-diff-submodule-option.sh
+++ b/t/t4041-diff-submodule-option.sh
@@ -207,17 +207,17 @@ EOF
 
 test_expect_success 'submodule contains untracked content (untracked ignored)' "
 	git diff-index -p --ignore-submodules=untracked --submodule=log HEAD >actual &&
-	echo -n '' | diff actual -
+	! test -s actual -
 "
 
 test_expect_success 'submodule contains untracked content (dirty ignored)' "
 	git diff-index -p --ignore-submodules=dirty --submodule=log HEAD >actual &&
-	echo -n '' | diff actual -
+	! test -s actual -
 "
 
 test_expect_success 'submodule contains untracked content (all ignored)' "
 	git diff-index -p --ignore-submodules=all --submodule=log HEAD >actual &&
-	echo -n '' | diff actual -
+	! test -s actual -
 "
 
 test_expect_success 'submodule contains untracked and modifed content' "
@@ -240,13 +240,13 @@ EOF
 test_expect_success 'submodule contains untracked and modifed content (dirty ignored)' "
 	echo new > sm1/foo6 &&
 	git diff-index -p --ignore-submodules=dirty --submodule=log HEAD >actual &&
-	echo -n '' | diff actual -
+	! test -s actual -
 "
 
 test_expect_success 'submodule contains untracked and modifed content (all ignored)' "
 	echo new > sm1/foo6 &&
 	git diff-index -p --ignore-submodules --submodule=log HEAD >actual &&
-	echo -n '' | diff actual -
+	! test -s actual -
 "
 
 test_expect_success 'submodule contains modifed content' "
@@ -295,7 +295,7 @@ EOF
 
 test_expect_success 'modified submodule contains untracked content (all ignored)' "
 	git diff-index -p --ignore-submodules=all --submodule=log HEAD >actual &&
-	echo -n '' | diff actual -
+	! test -s actual -
 "
 
 test_expect_success 'modified submodule contains untracked and modifed content' "
@@ -331,7 +331,7 @@ EOF
 test_expect_success 'modified submodule contains untracked and modifed content (all ignored)' "
 	echo modification >> sm1/foo6 &&
 	git diff-index -p --ignore-submodules --submodule=log HEAD >actual &&
-	echo -n '' | diff actual -
+	! test -s actual -
 "
 
 test_expect_success 'modified submodule contains modifed content' "
-- 
1.7.1.756.gb48b1