diff --git a/lib/common/tests/nvpair/Makefile.am b/lib/common/tests/nvpair/Makefile.am
index cfd800a7e1..c6f5984315 100644
--- a/lib/common/tests/nvpair/Makefile.am
+++ b/lib/common/tests/nvpair/Makefile.am
@@ -1,24 +1,25 @@
 #
 # Copyright 2021-2024 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.
 #
 
 include $(top_srcdir)/mk/common.mk
 include $(top_srcdir)/mk/tap.mk
 include $(top_srcdir)/mk/unittest.mk
 
 # Add "_test" to the end of all test program names to simplify .gitignore.
 check_PROGRAMS = crm_meta_name_test		\
 		 crm_meta_value_test		\
 		 pcmk__cmp_nvpair_blocks_test	\
 		 pcmk__xe_attr_is_true_test 	\
 		 pcmk__xe_get_bool_attr_test 	\
 		 pcmk__xe_get_datetime_test	\
 		 pcmk__xe_get_flags_test	\
-		 pcmk__xe_set_bool_attr_test
+		 pcmk__xe_set_bool_attr_test	\
+		 pcmk__unpack_nvpair_block_test
 
 TESTS = $(check_PROGRAMS)
diff --git a/lib/common/tests/nvpair/pcmk__unpack_nvpair_block_test.c b/lib/common/tests/nvpair/pcmk__unpack_nvpair_block_test.c
new file mode 100644
index 0000000000..ec7ba2f499
--- /dev/null
+++ b/lib/common/tests/nvpair/pcmk__unpack_nvpair_block_test.c
@@ -0,0 +1,187 @@
+/*
+ * Copyright 2024 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.
+ */
+
+#include <crm_internal.h>
+
+#include <crm/common/unittest_internal.h>
+#include <crm/common/xml_internal.h>
+
+#define XML_PASSING_RULE                                    \
+    "<" PCMK_XE_RULE " " PCMK_XA_ID "='rp' >\n"             \
+      "<" PCMK_XE_DATE_EXPRESSION " " PCMK_XA_ID "='ep' "   \
+          PCMK_XA_OPERATION "='" PCMK_VALUE_GT "' "         \
+          PCMK_XA_START "='1950-01-01 00:00:00' />\n"       \
+    "</" PCMK_XE_RULE ">\n"
+
+#define XML_FAILING_RULE                                    \
+    "<" PCMK_XE_RULE " " PCMK_XA_ID "='rf' >\n"             \
+      "<" PCMK_XE_DATE_EXPRESSION " " PCMK_XA_ID "='ef' "   \
+          PCMK_XA_OPERATION "='" PCMK_VALUE_LT "' "         \
+          PCMK_XA_END "='1950-01-01 00:00:00' />\n"         \
+    "</" PCMK_XE_RULE ">\n"
+
+#define XML_NVPAIRS_1                                       \
+    "<" PCMK_XE_NVPAIR " " PCMK_XA_ID "='nvp1-1' "          \
+        PCMK_XA_NAME "='name1' " PCMK_XA_VALUE "='1' />\n"  \
+    "<" PCMK_XE_NVPAIR " " PCMK_XA_ID "='nvp1-2' "          \
+        PCMK_XA_NAME "='name2' " PCMK_XA_VALUE "='1' />\n"
+
+#define XML_NVPAIRS_2                                       \
+    "<" PCMK_XE_NVPAIR " " PCMK_XA_ID "='nvp2-1' "          \
+        PCMK_XA_NAME "='name1' " PCMK_XA_VALUE "='2' />\n"  \
+    "<" PCMK_XE_NVPAIR " " PCMK_XA_ID "='nvp2-2' "          \
+        PCMK_XA_NAME "='name2' " PCMK_XA_VALUE "='2' />\n"  \
+    "<" PCMK_XE_NVPAIR " " PCMK_XA_ID "='nvp2-3' "          \
+        PCMK_XA_NAME "='name3' " PCMK_XA_VALUE "='2' />\n"
+
+static void
+invalid_args(void **state)
+{
+    pcmk__nvpair_unpack_t unpack_data = {
+        .values = NULL,
+        .rule_input = {
+            .now = NULL,
+        },
+    };
+
+    xmlNode *xml = pcmk__xml_parse("<xml/>");
+
+    assert_non_null(xml);
+
+    pcmk__assert_asserts(pcmk__unpack_nvpair_block(NULL, NULL));
+    pcmk__assert_asserts(pcmk__unpack_nvpair_block(NULL, &unpack_data));
+    pcmk__assert_asserts(pcmk__unpack_nvpair_block(xml, NULL));
+    pcmk__assert_asserts(pcmk__unpack_nvpair_block(xml, &unpack_data));
+
+    unpack_data.values = g_hash_table_new(NULL, NULL);
+    pcmk__assert_asserts(pcmk__unpack_nvpair_block(NULL, &unpack_data));
+    g_hash_table_destroy(unpack_data.values);
+
+    pcmk__xml_free(xml);
+}
+
+static void
+with_rules(void **state) {
+    crm_time_t *now = crm_time_new("2024-01-01 15:00:00");
+    pcmk__nvpair_unpack_t unpack_data = {
+        .values = pcmk__strkey_table(free, free),
+        .rule_input = {
+            .now = now,
+        },
+    };
+
+    xmlNode *xml = NULL;
+
+    xml = pcmk__xml_parse("<xml>\n" XML_NVPAIRS_1 XML_PASSING_RULE "</xml>\n");
+    assert_non_null(xml);
+    pcmk__unpack_nvpair_block(xml, &unpack_data);
+    assert_int_equal(g_hash_table_size(unpack_data.values), 2);
+    assert_string_equal(g_hash_table_lookup(unpack_data.values, "name1"), "1");
+    assert_string_equal(g_hash_table_lookup(unpack_data.values, "name2"), "1");
+    pcmk__xml_free(xml);
+
+    xml = pcmk__xml_parse("<xml>\n" XML_NVPAIRS_2 XML_FAILING_RULE "</xml>\n");
+    assert_non_null(xml);
+    pcmk__unpack_nvpair_block(xml, &unpack_data);
+    assert_int_equal(g_hash_table_size(unpack_data.values), 2);
+    assert_string_equal(g_hash_table_lookup(unpack_data.values, "name1"), "1");
+    assert_string_equal(g_hash_table_lookup(unpack_data.values, "name2"), "1");
+    assert_null(g_hash_table_lookup(unpack_data.values, "name3"));
+
+    pcmk__xml_free(xml);
+    crm_time_free(now);
+    g_hash_table_destroy(unpack_data.values);
+}
+
+static void
+without_overwrite(void **state)
+{
+    pcmk__nvpair_unpack_t unpack_data = {
+        .values = pcmk__strkey_table(free, free),
+        .overwrite = false,
+    };
+
+    xmlNode *xml = NULL;
+
+    xml = pcmk__xml_parse("<xml>\n" XML_NVPAIRS_1 "</xml>\n");
+    assert_non_null(xml);
+    pcmk__unpack_nvpair_block(xml, &unpack_data);
+    assert_int_equal(g_hash_table_size(unpack_data.values), 2);
+    assert_string_equal(g_hash_table_lookup(unpack_data.values, "name1"), "1");
+    assert_string_equal(g_hash_table_lookup(unpack_data.values, "name2"), "1");
+    pcmk__xml_free(xml);
+
+    xml = pcmk__xml_parse("<xml>\n" XML_NVPAIRS_2 "</xml>\n");
+    assert_non_null(xml);
+    pcmk__unpack_nvpair_block(xml, &unpack_data);
+    assert_int_equal(g_hash_table_size(unpack_data.values), 3);
+    assert_string_equal(g_hash_table_lookup(unpack_data.values, "name1"), "1");
+    assert_string_equal(g_hash_table_lookup(unpack_data.values, "name2"), "1");
+    assert_string_equal(g_hash_table_lookup(unpack_data.values, "name3"), "2");
+    pcmk__xml_free(xml);
+
+    g_hash_table_destroy(unpack_data.values);
+}
+
+static void
+with_overwrite(void **state)
+{
+    pcmk__nvpair_unpack_t unpack_data = {
+        .values = pcmk__strkey_table(free, free),
+        .overwrite = true,
+    };
+
+    xmlNode *xml = NULL;
+
+    xml = pcmk__xml_parse("<xml>\n" XML_NVPAIRS_1 "</xml>\n");
+    assert_non_null(xml);
+    pcmk__unpack_nvpair_block(xml, &unpack_data);
+    assert_int_equal(g_hash_table_size(unpack_data.values), 2);
+    assert_string_equal(g_hash_table_lookup(unpack_data.values, "name1"), "1");
+    assert_string_equal(g_hash_table_lookup(unpack_data.values, "name2"), "1");
+    pcmk__xml_free(xml);
+
+    xml = pcmk__xml_parse("<xml>\n" XML_NVPAIRS_2 "</xml>\n");
+    assert_non_null(xml);
+    pcmk__unpack_nvpair_block(xml, &unpack_data);
+    assert_int_equal(g_hash_table_size(unpack_data.values), 3);
+    assert_string_equal(g_hash_table_lookup(unpack_data.values, "name1"), "2");
+    assert_string_equal(g_hash_table_lookup(unpack_data.values, "name2"), "2");
+    assert_string_equal(g_hash_table_lookup(unpack_data.values, "name3"), "2");
+    pcmk__xml_free(xml);
+
+    g_hash_table_destroy(unpack_data.values);
+}
+
+static void
+attributes_child(void **state)
+{
+    pcmk__nvpair_unpack_t unpack_data = {
+        .values = pcmk__strkey_table(free, free),
+    };
+
+    xmlNode *xml = pcmk__xml_parse("<xml>\n<" PCMK__XE_ATTRIBUTES ">\n"
+                                   XML_NVPAIRS_1
+                                   "</" PCMK__XE_ATTRIBUTES ">\n</xml>\n");
+    assert_non_null(xml);
+    pcmk__unpack_nvpair_block(xml, &unpack_data);
+    assert_int_equal(g_hash_table_size(unpack_data.values), 2);
+    assert_string_equal(g_hash_table_lookup(unpack_data.values, "name1"), "1");
+    assert_string_equal(g_hash_table_lookup(unpack_data.values, "name2"), "1");
+    pcmk__xml_free(xml);
+
+    g_hash_table_destroy(unpack_data.values);
+}
+
+PCMK__UNIT_TEST(pcmk__xml_test_setup_group, pcmk__xml_test_teardown_group,
+                cmocka_unit_test(invalid_args),
+                cmocka_unit_test(with_rules),
+                cmocka_unit_test(without_overwrite),
+                cmocka_unit_test(with_overwrite),
+                cmocka_unit_test(attributes_child))