t/test-lib.sh: add test_external and test_external_without_stderr

This is for running external test scripts in other programming
languages that provide continuous output about their tests.  Using
test_expect_success (like "test_expect_success 'description' 'perl
test-script.pl'") doesn't suffice here because test_expect_success
eats stdout in non-verbose mode, which is not fixable without major
file descriptor trickery.

Signed-off-by: Lea Wiemann <LeWiemann@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/t/test-lib.sh b/t/test-lib.sh
index c861141667eb03eb42f559cbe174c6a76dd704c9..4be466edb79fb7b509888ef5adac5f09c076bb33 100644 (file)
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -302,6 +302,64 @@ test_expect_code () {
        echo >&3 ""
 }
 
+# test_external runs external test scripts that provide continuous
+# test output about their progress, and succeeds/fails on
+# zero/non-zero exit code.  It outputs the test output on stdout even
+# in non-verbose mode, and announces the external script with "* run
+# <n>: ..." before running it.  When providing relative paths, keep in
+# mind that all scripts run in "trash directory".
+# Usage: test_external description command arguments...
+# Example: test_external 'Perl API' perl ../path/to/test.pl
+test_external () {
+       test "$#" -eq 3 ||
+       error >&5 "bug in the test script: not 3 parameters to test_external"
+       descr="$1"
+       shift
+       if ! test_skip "$descr" "$@"
+       then
+               # Announce the script to reduce confusion about the
+               # test output that follows.
+               say_color "" " run $(expr "$test_count" + 1): $descr ($*)"
+               # Run command; redirect its stderr to &4 as in
+               # test_run_, but keep its stdout on our stdout even in
+               # non-verbose mode.
+               "$@" 2>&4
+               if [ "$?" = 0 ]
+               then
+                       test_ok_ "$descr"
+               else
+                       test_failure_ "$descr" "$@"
+               fi
+       fi
+}
+
+# Like test_external, but in addition tests that the command generated
+# no output on stderr.
+test_external_without_stderr () {
+       # The temporary file has no (and must have no) security
+       # implications.
+       tmp="$TMPDIR"; if [ -z "$tmp" ]; then tmp=/tmp; fi
+       stderr="$tmp/git-external-stderr.$$.tmp"
+       test_external "$@" 4> "$stderr"
+       [ -f "$stderr" ] || error "Internal error: $stderr disappeared."
+       descr="no stderr: $1"
+       shift
+       say >&3 "expecting no stderr from previous command"
+       if [ ! -s "$stderr" ]; then
+               rm "$stderr"
+               test_ok_ "$descr"
+       else
+               if [ "$verbose" = t ]; then
+                       output=`echo; echo Stderr is:; cat "$stderr"`
+               else
+                       output=
+               fi
+               # rm first in case test_failure exits.
+               rm "$stderr"
+               test_failure_ "$descr" "$@" "$output"
+       fi
+}
+
 # This is not among top-level (test_expect_success | test_expect_failure)
 # but is a prefix that can be used in the test script, like:
 #