test-lib: Infrastructure to test and check for prerequisites
Some tests can be run only if a particular prerequisite is available. For
example, some tests require that an UTF-8 locale is available. Here we
introduce functions that are used in this way:
1. Insert code that checks whether the prerequisite is available. If it is,
call test_set_prereq with an arbitrary tag name that subsequently can be
used to check for the prerequisite:
case $LANG in
*.utf-8)
test_set_prereq UTF8
;;
esac
2. In the calls to test_expect_success pass the tag name:
test_expect_success UTF8 '...description...' '...tests...'
3. There is an auxiliary predicate that can be used anywhere to test for
a prerequisite explicitly:
if test_have_prereq UTF8
then
...code to be skipped if prerequisite is not available...
fi
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
diff --git a/t/test-lib.sh b/t/test-lib.sh
index 0a0696a..3c65cfe 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -247,6 +247,31 @@
git update-index --add "--chmod=$@"
}
+# Use test_set_prereq to tell that a particular prerequisite is available.
+# The prerequisite can later be checked for in two ways:
+#
+# - Explicitly using test_have_prereq.
+#
+# - Implicitly by specifying the prerequisite tag in the calls to
+# test_expect_{success,failure,code}.
+#
+# The single parameter is the prerequisite tag (a simple word, in all
+# capital letters by convention).
+
+test_set_prereq () {
+ satisfied="$satisfied$1 "
+}
+satisfied=" "
+
+test_have_prereq () {
+ case $satisfied in
+ *" $1 "*)
+ : yes, have it ;;
+ *)
+ ! : nope ;;
+ esac
+}
+
# You are not expected to call test_ok_ and test_failure_ directly, use
# the text_expect_* functions instead.
@@ -293,6 +318,11 @@
to_skip=t
esac
done
+ if test -z "$to_skip" && test -n "$prereq" &&
+ ! test_have_prereq "$prereq"
+ then
+ to_skip=t
+ fi
case "$to_skip" in
t)
say_color skip >&3 "skipping test: $@"
@@ -306,8 +336,9 @@
}
test_expect_failure () {
+ test "$#" = 3 && { prereq=$1; shift; } || prereq=
test "$#" = 2 ||
- error "bug in the test script: not 2 parameters to test-expect-failure"
+ error "bug in the test script: not 2 or 3 parameters to test-expect-failure"
if ! test_skip "$@"
then
say >&3 "checking known breakage: $2"
@@ -323,8 +354,9 @@
}
test_expect_success () {
+ test "$#" = 3 && { prereq=$1; shift; } || prereq=
test "$#" = 2 ||
- error "bug in the test script: not 2 parameters to test-expect-success"
+ error "bug in the test script: not 2 or 3 parameters to test-expect-success"
if ! test_skip "$@"
then
say >&3 "expecting success: $2"
@@ -340,8 +372,9 @@
}
test_expect_code () {
+ test "$#" = 4 && { prereq=$1; shift; } || prereq=
test "$#" = 3 ||
- error "bug in the test script: not 3 parameters to test-expect-code"
+ error "bug in the test script: not 3 or 4 parameters to test-expect-code"
if ! test_skip "$@"
then
say >&3 "expecting exit code $1: $3"
@@ -365,8 +398,9 @@
# Usage: test_external description command arguments...
# Example: test_external 'Perl API' perl ../path/to/test.pl
test_external () {
- test "$#" -eq 3 ||
- error >&5 "bug in the test script: not 3 parameters to test_external"
+ test "$#" = 4 && { prereq=$1; shift; } || prereq=
+ test "$#" = 3 ||
+ error >&5 "bug in the test script: not 3 or 4 parameters to test_external"
descr="$1"
shift
if ! test_skip "$descr" "$@"
