Fixed commands with a trailing whitespace

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

@@ -153,7 +153,9 @@ public class CommandDispatcher<S> {
 
             context.withCommand(child.getCommand());
             if (reader.canRead()) {
-                reader.skip();
+                if (reader.canRead(2)) {
+                    reader.skip();
+                }
                 if (child.getRedirect() != null) {
                     final CommandContextBuilder<S> childContext = new CommandContextBuilder<>(this, source, reader.getCursor());
                     childContext.withNode(child.getRedirect(), new StringRange(reader.getCursor(), reader.getCursor()));

src/test/java/com/mojang/brigadier/CommandDispatcherTest.java

@@ -173,6 +173,16 @@ public class CommandDispatcherTest {
         verify(subCommand).run(any(CommandContext.class));
     }
 
+    @SuppressWarnings("unchecked")
+    @Test
+    public void testParseIncomplete() throws Exception {
+        subject.register(literal("foo").then(literal("bar").executes(command)));
+
+        final ParseResults<Object> parse = subject.parse("foo ", source);
+        assertThat(parse.getReader().getRemaining(), equalTo(" "));
+        assertThat(parse.getContext().getNodes().size(), is(1));
+    }
+
     @SuppressWarnings("unchecked")
     @Test
     public void testExecuteAmbiguiousParentSubcommand() throws Exception {