t7400: clarify submodule update tests

In particular, add a missing && to the update --init test.

The goal is to make it clearer what happened when one of these
tests fails.  The update --init test is currently (consistently)
failing on a few unusual machines.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t7400-submodule-basic.sh

@@ -28,9 +28,6 @@ test_expect_success 'setup - repository in init subdirectory' '
 		git commit -m "submodule commit 1" &&
 		git tag -a -m "rev-1" rev-1
 	)
-	rev1=$(cd init && git rev-parse HEAD) &&
-	printf "rev1: %s\n" "$rev1" &&
-	test -n "$rev1"
 '
 
 test_expect_success 'setup - commit with gitlink' '
@@ -44,11 +41,6 @@ test_expect_success 'setup - hide init subdirectory' '
 	mv init .subrepo
 '
 
-test_expect_success 'setup - add an example entry to .gitmodules' '
-	GIT_CONFIG=.gitmodules \
-	git config submodule.example.url git://example.com/init.git
-'
-
 test_expect_success 'setup - repository to add submodules to' '
 	git init addtest
 '
@@ -69,6 +61,7 @@ inspect() {
 		cd "$dir" &&
 		listbranches >"$dotdot/heads" &&
 		{ git symbolic-ref HEAD || :; } >"$dotdot/head" &&
+		git rev-parse HEAD >"$dotdot/head-sha1" &&
 		git update-index --refresh &&
 		git diff-files --exit-code &&
 		git clean -n -d -x >"$dotdot/untracked"
@@ -181,131 +174,129 @@ test_expect_success 'submodule add with ./, /.. and // in path' '
 	test_cmp empty untracked
 '
 
+test_expect_success 'setup - add an example entry to .gitmodules' '
+	GIT_CONFIG=.gitmodules \
+	git config submodule.example.url git://example.com/init.git
+'
+
 test_expect_success 'status should fail for unmapped paths' '
-	if git submodule status
-	then
-		echo "[OOPS] submodule status succeeded"
-		false
-	elif ! GIT_CONFIG=.gitmodules git config submodule.example.path init
-	then
-		echo "[OOPS] git config failed to update .gitmodules"
-		false
-	fi
+	test_must_fail git submodule status
+'
+
+test_expect_success 'setup - map path in .gitmodules' '
+	cat <<\EOF >expect &&
+[submodule "example"]
+	url = git://example.com/init.git
+	path = init
+EOF
+
+	GIT_CONFIG=.gitmodules git config submodule.example.path init &&
+
+	test_cmp expect .gitmodules
 '
 
 test_expect_success 'status should only print one line' '
-	lines=$(git submodule status | wc -l) &&
-	test $lines = 1
+	git submodule status >lines &&
+	test $(wc -l <lines) = 1
+'
+
+test_expect_success 'setup - fetch commit name from submodule' '
+	rev1=$(cd .subrepo && git rev-parse HEAD) &&
+	printf "rev1: %s\n" "$rev1" &&
+	test -n "$rev1"
 '
 
 test_expect_success 'status should initially be "missing"' '
-	git submodule status | grep "^-$rev1"
+	git submodule status >lines &&
+	grep "^-$rev1" lines
 '
 
 test_expect_success 'init should register submodule url in .git/config' '
+	echo git://example.com/init.git >expect &&
+
 	git submodule init &&
-	url=$(git config submodule.example.url) &&
-	if test "$url" != "git://example.com/init.git"
-	then
-		echo "[OOPS] init succeeded but submodule url is wrong"
-		false
-	elif test_must_fail git config submodule.example.url ./.subrepo
-	then
-		echo "[OOPS] init succeeded but update of url failed"
-		false
-	fi
+	git config submodule.example.url >url &&
+	git config submodule.example.url ./.subrepo &&
+
+	test_cmp expect url
 '
 
 test_expect_success 'update should fail when path is used by a file' '
+	echo hello >expect &&
+
 	echo "hello" >init &&
-	if git submodule update
-	then
-		echo "[OOPS] update should have failed"
-		false
-	elif test "$(cat init)" != "hello"
-	then
-		echo "[OOPS] update failed but init file was molested"
-		false
-	else
-		rm init
-	fi
+	test_must_fail git submodule update &&
+
+	test_cmp expect init
 '
 
 test_expect_success 'update should fail when path is used by a nonempty directory' '
+	echo hello >expect &&
+
+	rm -fr init &&
 	mkdir init &&
 	echo "hello" >init/a &&
-	if git submodule update
-	then
-		echo "[OOPS] update should have failed"
-		false
-	elif test "$(cat init/a)" != "hello"
-	then
-		echo "[OOPS] update failed but init/a was molested"
-		false
-	else
-		rm init/a
-	fi
+
+	test_must_fail git submodule update &&
+
+	test_cmp expect init/a
 '
 
 test_expect_success 'update should work when path is an empty dir' '
-	rm -rf init &&
+	rm -fr init &&
+	rm -f head-sha1 &&
+	echo "$rev1" >expect &&
+
 	mkdir init &&
 	git submodule update &&
-	head=$(cd init && git rev-parse HEAD) &&
-	if test -z "$head"
-	then
-		echo "[OOPS] Failed to obtain submodule head"
-		false
-	elif test "$head" != "$rev1"
-	then
-		echo "[OOPS] Submodule head is $head but should have been $rev1"
-		false
-	fi
+
+	inspect init &&
+	test_cmp expect head-sha1
 '
 
 test_expect_success 'status should be "up-to-date" after update' '
-	git submodule status | grep "^ $rev1"
+	git submodule status >list &&
+	grep "^ $rev1" list
 '
 
 test_expect_success 'status should be "modified" after submodule commit' '
-	cd init &&
-	echo b >b &&
-	git add b &&
-	git commit -m "submodule commit 2" &&
-	rev2=$(git rev-parse HEAD) &&
-	cd .. &&
-	if test -z "$rev2"
-	then
-		echo "[OOPS] submodule git rev-parse returned nothing"
-		false
-	fi &&
-	git submodule status | grep "^+$rev2"
+	(
+		cd init &&
+		echo b >b &&
+		git add b &&
+		git commit -m "submodule commit 2"
+	) &&
+
+	rev2=$(cd init && git rev-parse HEAD) &&
+	test -n "$rev2" &&
+	git submodule status >list &&
+
+	grep "^+$rev2" list
 '
 
 test_expect_success 'the --cached sha1 should be rev1' '
-	git submodule --cached status | grep "^+$rev1"
+	git submodule --cached status >list &&
+	grep "^+$rev1" list
 '
 
 test_expect_success 'git diff should report the SHA1 of the new submodule commit' '
-	git diff | grep "^+Subproject commit $rev2"
+	git diff >diff &&
+	grep "^+Subproject commit $rev2" diff
 '
 
 test_expect_success 'update should checkout rev1' '
+	rm -f head-sha1 &&
+	echo "$rev1" >expect &&
+
 	git submodule update init &&
-	head=$(cd init && git rev-parse HEAD) &&
-	if test -z "$head"
-	then
-		echo "[OOPS] submodule git rev-parse returned nothing"
-		false
-	elif test "$head" != "$rev1"
-	then
-		echo "[OOPS] init did not checkout correct head"
-		false
-	fi
+	inspect init &&
+
+	test_cmp expect head-sha1
 '
 
 test_expect_success 'status should be "up-to-date" after update' '
-	git submodule status | grep "^ $rev1"
+	git submodule status >list &&
+	grep "^ $rev1" list
 '
 
 test_expect_success 'checkout superproject with subproject already present' '
@@ -314,6 +305,8 @@ test_expect_success 'checkout superproject with subproject already present' '
 '
 
 test_expect_success 'apply submodule diff' '
+	>empty &&
+
 	git branch second &&
 	(
 		cd init &&
@@ -326,21 +319,24 @@ test_expect_success 'apply submodule diff' '
 	git format-patch -1 --stdout >P.diff &&
 	git checkout second &&
 	git apply --index P.diff &&
-	D=$(git diff --cached master) &&
-	test -z "$D"
+
+	git diff --cached master >staged &&
+	test_cmp empty staged
 '
 
 test_expect_success 'update --init' '
-
 	mv init init2 &&
 	git config -f .gitmodules submodule.example.url "$(pwd)/init2" &&
-	git config --remove-section submodule.example
+	git config --remove-section submodule.example &&
+	test_must_fail git config submodule.example.url &&
+
 	git submodule update init > update.out &&
+	cat update.out &&
 	grep "not initialized" update.out &&
-	test ! -d init/.git &&
+	! test -d init/.git &&
+
 	git submodule update --init init &&
 	test -d init/.git
-
 '
 
 test_expect_success 'do not add files from a submodule' '