diff --git a/tests/tests.py b/tests/tests.py
index 7489c0d..c037fef 100644
--- a/tests/tests.py
+++ b/tests/tests.py
@@ -1328,6 +1328,82 @@ class TestPromptPostProcessor(TestPromptPostProcessorBase):
             ppp=self.nocupppp,
         )
 
+    # NaN/undefined variable integer comparison tests
+
+    def test_cmd_if_undefined_var_int_compare_warn(self):  # undefined var integer compare with on_warning=warn
+        self.process(
+            PromptPair(
+                "<ppp:if undefined_var gt 0>YES<ppp:else>NO<ppp:/if>",
+                "",
+            ),
+            PromptPair("NO", ""),
+            ppp=PromptPostProcessor(
+                self.ppp_logger,
+                self.interrupt,
+                self.def_env_info,
+                {**self.defopts, "on_warning": PromptPostProcessor.ONWARNING_CHOICES.warn.value},
+                self.grammar_content,
+                self.wildcards_obj,
+                self.extranetwork_maps_obj,
+            ),
+        )
+
+    def test_cmd_if_undefined_var_int_compare_stop(self):  # undefined var integer compare with on_warning=stop
+        self.process(
+            PromptPair(
+                "<ppp:if undefined_var gt 0>YES<ppp:else>NO<ppp:/if>",
+                "",
+            ),
+            PromptPair("", ""),
+            interrupted=True,
+        )
+
+    def test_cmd_if_nonnumeric_var_int_compare_warn(self):  # non-numeric var integer compare with on_warning=warn
+        self.process(
+            PromptPair(
+                "<ppp:set myvar>abc<ppp:/set><ppp:if myvar gt 0>YES<ppp:else>NO<ppp:/if>",
+                "",
+            ),
+            PromptPair("NO", ""),
+            ppp=PromptPostProcessor(
+                self.ppp_logger,
+                self.interrupt,
+                self.def_env_info,
+                {**self.defopts, "on_warning": PromptPostProcessor.ONWARNING_CHOICES.warn.value},
+                self.grammar_content,
+                self.wildcards_obj,
+                self.extranetwork_maps_obj,
+            ),
+        )
+
+    def test_cmd_if_nonnumeric_var_int_compare_stop(self):  # non-numeric var integer compare with on_warning=stop
+        self.process(
+            PromptPair(
+                "<ppp:set myvar>abc<ppp:/set><ppp:if myvar gt 0>YES<ppp:else>NO<ppp:/if>",
+                "",
+            ),
+            PromptPair("", ""),
+            interrupted=True,
+        )
+
+    def test_cmd_if_empty_var_int_compare(self):  # empty string var integer compare with on_warning=warn
+        self.process(
+            PromptPair(
+                "<ppp:set myvar><ppp:/set><ppp:if myvar gt 0>YES<ppp:else>NO<ppp:/if>",
+                "",
+            ),
+            PromptPair("NO", ""),
+            ppp=PromptPostProcessor(
+                self.ppp_logger,
+                self.interrupt,
+                self.def_env_info,
+                {**self.defopts, "on_warning": PromptPostProcessor.ONWARNING_CHOICES.warn.value},
+                self.grammar_content,
+                self.wildcards_obj,
+                self.extranetwork_maps_obj,
+            ),
+        )
+
 
 if __name__ == "__main__":
     unittest.main()