test-lib: add the test_pause convenience function

Since 781f76b15 (test-lib: redirect stdin of tests) you can't simply put a
"bash &&" into a test for debugging purposes anymore. Instead you'll have
to use "bash <&6 >&3 2>&4".

As that invocation is not that easy to remember add the test_pause
convenience function. It invokes "$SHELL_PATH" to provide a sane shell
for the user.

This function also checks if the -v flag is given and will error out if
that is not the case instead of letting the test hang until ^D is pressed.

Signed-off-by: Jens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 13 insertions, 0 deletions

diff --git a/t/README b/t/README
index c85abaffb3..c09c582c16 100644
--- a/t/README
+++ b/t/README
@@ -548,6 +548,19 @@ library for your script to use.
 		...
 	'
 
+ - test_pause
+
+	This command is useful for writing and debugging tests and must be
+	removed before submitting. It halts the execution of the test and
+	spawns a shell in the trash directory. Exit the shell to continue
+	the test. Example:
+
+	test_expect_success 'test' '
+		git do-something >actual &&
+		test_pause &&
+		test_cmp expected actual
+	'
+
 Prerequisites
 -------------