CODEC-314: Add unit test

Signed-off-by: Arthur Chan <arthur.chan@adalogics.com>

src/test/java/org/apache/commons/codec/net/PercentCodecTest.java

@@ -18,6 +18,7 @@
 package org.apache.commons.codec.net;
 
 import static org.junit.jupiter.api.Assertions.assertArrayEquals;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertNull;
 import static org.junit.jupiter.api.Assertions.assertThrows;
@@ -105,6 +106,13 @@ public void testEncodeUnsupportedObject() {
         assertThrows(EncoderException.class, () -> percentCodec.encode("test"));
     }
 
+    @Test
+    public void testInvalidByte() {
+        byte[] invalid = {(byte)-1};
+
+        assertDoesNotThrow(() -> new PercentCodec(invalid, true));
+    }
+
     @Test
     public void testPercentEncoderDecoderWithNullOrEmptyInput() throws Exception {
         final PercentCodec percentCodec = new PercentCodec(null, true);