test: add function to explicitly check for external dependencies

[notmuch] / test / test-lib.sh

diff --git a/test/test-lib.sh b/test/test-lib.sh
index 99b9e8b8096386484f27fea028e75292a93e1007..2422e32d9ece07aae03871fb0c81ea7b2825608c 100644 (file)
--- a/test/test-lib.sh
+++ b/test/test-lib.sh
@@ -555,12 +555,26 @@ test_declare_external_prereq () {
 
        hash $binary 2>/dev/null || eval "
 $binary () {
+       test_missing_external_prereq_${binary}_=t
        echo -n \"\$test_subtest_missing_external_prereqs_\" | grep -e \" $name \" ||
        test_subtest_missing_external_prereqs_=\"$test_subtest_missing_external_prereqs_ $name\"
        false
 }"
 }
 
+# Explicitly require external prerequisite.  Useful when binary is
+# called indirectly (e.g. from emacs).
+# Returns success if dependency is available, failure otherwise.
+test_require_external_prereq () {
+       binary="$1"
+       if [ "$(eval echo -n \$test_missing_external_prereq_${binary}_)" = t ]; then
+               # dependency is missing, call the replacement function to note it
+               eval "$binary"
+       else
+               true
+       fi
+}
+
 # You are not expected to call test_ok_ and test_failure_ directly, use
 # the text_expect_* functions instead.
 
@@ -1123,3 +1137,10 @@ test -z "$NO_PYTHON" && test_set_prereq PYTHON
 # test whether the filesystem supports symbolic links
 ln -s x y 2>/dev/null && test -h y 2>/dev/null && test_set_prereq SYMLINKS
 rm -f y
+
+# declare prerequisites for external binaries used in tests
+test_declare_external_prereq dtach
+test_declare_external_prereq emacs
+test_declare_external_prereq emacsclient
+test_declare_external_prereq gdb
+test_declare_external_prereq gpg