Updated StringArgumentType.escapeIfRequired to new string rules

src/main/java/com/mojang/brigadier/StringReader.java

@@ -137,7 +137,7 @@ public class StringReader implements ImmutableStringReader {
         }
     }
 
-    private static boolean isAllowedInUnquotedString(final char c) {
+    public static boolean isAllowedInUnquotedString(final char c) {
         return c >= '0' && c <= '9'
             || c >= 'A' && c <= 'Z'
             || c >= 'a' && c <= 'z'

src/main/java/com/mojang/brigadier/arguments/StringArgumentType.java

@@ -52,8 +52,10 @@ public class StringArgumentType implements ArgumentType<String> {
     }
 
     public static String escapeIfRequired(final String input) {
-        if (input.contains("\\") || input.contains("\"") || input.contains(CommandDispatcher.ARGUMENT_SEPARATOR)) {
-            return escape(input);
+        for (final char c : input.toCharArray()) {
+            if (!StringReader.isAllowedInUnquotedString(c)) {
+                return escape(input);
+            }
         }
         return input;
     }

src/test/java/com/mojang/brigadier/arguments/StringArgumentTypeTest.java

@@ -58,7 +58,7 @@ public class StringArgumentTypeTest {
 
     @Test
     public void testEscapeIfRequired_notRequired() throws Exception {
-        assertThat(escapeIfRequired("hello!"), is(equalTo("hello!")));
+        assertThat(escapeIfRequired("hello"), is(equalTo("hello")));
         assertThat(escapeIfRequired(""), is(equalTo("")));
     }