[PATCH 3/3] test: implement and document NOTMUCH_TEST_QUIET variable usage

[Tomi Ollila]

When NOTMUCH_TEST_QUIET environment variable is set to non-null value
messages when new test script starts and when test PASSes are disabled.
This eases picking the cases when tests FAIL (as those are still printed).
---
 test/README      |  8 ++++++++
 test/basic       |  4 ++--
 test/test-lib.sh | 11 ++++++++++-
 3 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/test/README b/test/README
index d12cff2..79a9b1b 100644
--- a/test/README
+++ b/test/README
@@ -74,10 +74,18 @@ the tests in one of the following ways.
 
 	TEST_EMACS=my-special-emacs TEST_EMACSCLIENT=my-emacsclient make test
 	TEST_EMACS=my-special-emacs TEST_EMACSCLIENT=my-emacsclient ./emacs
 	make test TEST_EMACS=my-special-emacs TEST_EMACSCLIENT=my-emacsclient
 
+Quiet Execution
+---------------
+
+Normally, when new script starts and when test PASSes you get a message
+printed on screen. This printing can be disabled by setting the
+NOTMUCH_TEST_QUIET variable to a non-null value. Message on test
+failures and skips are still printed.
+
 Skipping Tests
 --------------
 If, for any reason, you need to skip one or more tests, you can do so
 by setting the NOTMUCH_SKIP_TESTS variable to the name of one or more
 sections of tests.
diff --git a/test/basic b/test/basic
index 64eb7d7..f7eed32 100755
--- a/test/basic
+++ b/test/basic
@@ -72,16 +72,16 @@ suppress_diff_date() {
     sed -e 's/\(.*\-\-\- test-verbose\.4\.\expected\).*/\1/' \
 	-e 's/\(.*\+\+\+ test-verbose\.4\.\output\).*/\1/'
 }
 
 test_begin_subtest "Ensure that test output is suppressed unless the test fails"
-output=$(cd $TEST_DIRECTORY; ./test-verbose 2>&1 | suppress_diff_date)
+output=$(cd $TEST_DIRECTORY; NOTMUCH_TEST_QUIET= ./test-verbose 2>&1 | suppress_diff_date)
 expected=$(cat $EXPECTED/test-verbose-no | suppress_diff_date)
 test_expect_equal "$output" "$expected"
 
 test_begin_subtest "Ensure that -v does not suppress test output"
-output=$(cd $TEST_DIRECTORY; ./test-verbose -v 2>&1 | suppress_diff_date)
+output=$(cd $TEST_DIRECTORY; NOTMUCH_TEST_QUIET= ./test-verbose -v 2>&1 | suppress_diff_date)
 expected=$(cat $EXPECTED/test-verbose-yes | suppress_diff_date)
 # Do not include the results of test-verbose in totals
 rm $TEST_DIRECTORY/test-results/test-verbose
 rm -r $TEST_DIRECTORY/tmp.test-verbose
 test_expect_equal "$output" "$expected"
diff --git a/test/test-lib.sh b/test/test-lib.sh
index 34e0db6..9d4a807 100644
--- a/test/test-lib.sh
+++ b/test/test-lib.sh
@@ -196,11 +196,14 @@ print_test_description ()
 	test -z "$test_description_printed" || return 0
 	echo
 	echo $this_test: "Testing ${test_description}"
 	test_description_printed=1
 }
-print_test_description
+if [ -z "$NOTMUCH_TEST_QUIET" ]
+then
+	print_test_description
+fi
 
 exec 5>&1
 
 test_failure=0
 test_count=0
@@ -715,20 +718,26 @@ test_ok_ () {
 	if test "$test_subtest_known_broken_" = "t"; then
 		test_known_broken_ok_
 		return
 	fi
 	test_success=$(($test_success + 1))
+	if test -n "$NOTMUCH_TEST_QUIET"; then
+		return 0
+	fi
 	say_color pass "%-6s" "PASS"
 	echo " $test_subtest_name"
 }
 
 test_failure_ () {
 	if test "$test_subtest_known_broken_" = "t"; then
 		test_known_broken_failure_ "$@"
 		return
 	fi
 	test_failure=$(($test_failure + 1))
+	if test -n "$NOTMUCH_TEST_QUIET"; then
+		print_test_description
+	fi
 	test_failure_message_ "FAIL" "$test_subtest_name" "$@"
 	test "$immediate" = "" || { GIT_EXIT_OK=t; exit 1; }
 	return 1
 }
 
-- 
1.8.4.2