Throw exception when delimiter/separator are empty Strings

This case originally threw an unhelpful IndexOutOfBounds on MapArgument line 453
CommandAPI · willkroboth · Jun 9, 2023 · May 21, 2023 · May 21, 2023 · May 21, 2023
commit 72c7cd9e0c05c45c46439b8cd081eb44c82f369c
diff --git a/...mmandapi-bukkit-core/src/main/java/dev/jorel/commandapi/arguments/MapArgumentBuilder.java b/...mmandapi-bukkit-core/src/main/java/dev/jorel/commandapi/arguments/MapArgumentBuilder.java
@@ -54,6 +54,8 @@ public MapArgumentBuilder(String nodeName, String delimiter) {
 	 * @param separator the separator between a key and a value
 	 */
 	public MapArgumentBuilder(String nodeName, String delimiter, String separator) {
+		if(delimiter.length() == 0) throw new IllegalArgumentException("The delimiter cannot be an empty String!");
+		if(separator.length() == 0) throw new IllegalArgumentException("The separator cannot be an empty String!");
 		this.nodeName = nodeName;
 		this.delimiter = delimiter;
 		this.separator = separator;

diff --git a/...bukkit-test-tests/src/test/java/dev/jorel/commandapi/test/arguments/ArgumentMapTests.java b/...bukkit-test-tests/src/test/java/dev/jorel/commandapi/test/arguments/ArgumentMapTests.java
@@ -73,6 +73,11 @@ void exceptionTestWithMapArgument() {
 
 		command.withArguments(new StringArgument("string"));
 		assertThrows(GreedyArgumentException.class, command::register);
+
+		// Separator and delimiter cannot be empty strings
+		assertThrows(IllegalArgumentException.class, () -> new MapArgumentBuilder<>("map", ""));
+		assertThrows(IllegalArgumentException.class, () -> new MapArgumentBuilder<>("map", ":", ""));
+		assertDoesNotThrow(() -> new MapArgumentBuilder<>("map", ":", " "));
 	}
 
 	@Test