diff --git a/lib/common/tests/strings/Makefile.am b/lib/common/tests/strings/Makefile.am
index 33f8b98d12..1d6c7aabbe 100644
--- a/lib/common/tests/strings/Makefile.am
+++ b/lib/common/tests/strings/Makefile.am
@@ -1,38 +1,39 @@
 #
 # Copyright 2020-2021 the Pacemaker project contributors
 #
 # The version control history for this file may have further details.
 #
 # This source code is licensed under the GNU General Public License version 2
 # or later (GPLv2+) WITHOUT ANY WARRANTY.
 #
 
 AM_CPPFLAGS = -I$(top_srcdir)/include -I$(top_builddir)/include
 LDADD = $(top_builddir)/lib/common/libcrmcommon.la
 
 include $(top_srcdir)/mk/glib-tap.mk
 
 # Add each test program here.  Each test should be written as a little standalone
 # program using the glib unit testing functions.  See the documentation for more
 # information.
 #
 # https://developer.gnome.org/glib/unstable/glib-Testing.html
 #
 # Add "_test" to the end of all test program names to simplify .gitignore.
-test_programs =	crm_str_to_boolean_test 	\
+test_programs =	crm_is_true_test 	\
+		crm_str_to_boolean_test 	\
 		pcmk__add_word_test		\
 		pcmk__btoa_test			\
 		pcmk__char_in_any_str_test	\
 		pcmk__parse_ll_range_test	\
 		pcmk__scan_double_test		\
 		pcmk__str_any_of_test		\
 		pcmk__str_in_list_test		\
 		pcmk__strcmp_test
 
 # If any extra data needs to be added to the source distribution, add it to the
 # following list.
 dist_test_data =
 
 # If any extra data needs to be used by tests but should not be added to the
 # source distribution, add it to the following list.
 test_data =
diff --git a/lib/common/tests/strings/crm_is_true_test.c b/lib/common/tests/strings/crm_is_true_test.c
new file mode 100644
index 0000000000..20def0d9b7
--- /dev/null
+++ b/lib/common/tests/strings/crm_is_true_test.c
@@ -0,0 +1,61 @@
+/*
+ * Copyright 2021 the Pacemaker project contributors
+ *
+ * The version control history for this file may have further details.
+ *
+ * This source code is licensed under the GNU Lesser General Public License
+ * version 2.1 or later (LGPLv2.1+) WITHOUT ANY WARRANTY.
+ */
+
+#include <crm_internal.h>
+
+static void
+bad_input(void) {
+    g_assert_false(crm_is_true(NULL));
+}
+
+static void
+is_true(void) {
+    g_assert_true(crm_is_true("true"));
+    g_assert_true(crm_is_true("TrUe"));
+    g_assert_true(crm_is_true("on"));
+    g_assert_true(crm_is_true("ON"));
+    g_assert_true(crm_is_true("yes"));
+    g_assert_true(crm_is_true("yES"));
+    g_assert_true(crm_is_true("y"));
+    g_assert_true(crm_is_true("Y"));
+    g_assert_true(crm_is_true("1"));
+}
+
+static void
+is_false(void) {
+    g_assert_false(crm_is_true("false"));
+    g_assert_false(crm_is_true("fAlSe"));
+    g_assert_false(crm_is_true("off"));
+    g_assert_false(crm_is_true("OFF"));
+    g_assert_false(crm_is_true("no"));
+    g_assert_false(crm_is_true("No"));
+    g_assert_false(crm_is_true("n"));
+    g_assert_false(crm_is_true("N"));
+    g_assert_false(crm_is_true("0"));
+
+    g_assert_false(crm_is_true(""));
+    g_assert_false(crm_is_true("blahblah"));
+
+    g_assert_false(crm_is_true("truedat"));
+    g_assert_false(crm_is_true("onnn"));
+    g_assert_false(crm_is_true("yep"));
+    g_assert_false(crm_is_true("Y!"));
+    g_assert_false(crm_is_true("100"));
+}
+
+int
+main(int argc, char **argv)
+{
+    g_test_init(&argc, &argv, NULL);
+
+    g_test_add_func("/common/strings/crm_is_true/bad_input", bad_input);
+    g_test_add_func("/common/strings/crm_is_true/is_true", is_true);
+    g_test_add_func("/common/strings/crm_is_true/is_false", is_false);
+    return g_test_run();
+}