test: -loglevel raises on invalid values

test/functional/feature_logging.py

@@ -82,6 +82,23 @@ class LoggingTest(BitcoinTestFramework):
             match=ErrorMatch.FULL_REGEX,
         )
 
+        self.log.info("Test -loglevel raises when invalid values are passed")
+        self.nodes[0].assert_start_raises_init_error(
+            extra_args=["-loglevel=abc"],
+            expected_msg="Error: Unsupported global logging level -loglevel=abc. Valid values: info, debug, trace.",
+            match=ErrorMatch.FULL_REGEX,
+        )
+        self.nodes[0].assert_start_raises_init_error(
+            extra_args=["-loglevel=net:abc"],
+            expected_msg="Error: Unsupported category-specific logging level -loglevel=net:abc.",
+            match=ErrorMatch.PARTIAL_REGEX,
+        )
+        self.nodes[0].assert_start_raises_init_error(
+            extra_args=["-loglevel=net:info:abc"],
+            expected_msg="Error: Unsupported category-specific logging level -loglevel=net:info:abc.",
+            match=ErrorMatch.PARTIAL_REGEX,
+        )
+
 
 if __name__ == '__main__':
     LoggingTest().main()