From fbf3546f18e8de57138aca43b4a91c9d7752c7c0 Mon Sep 17 00:00:00 2001
From: Nathan Adams <dinnerbone@dinnerbone.com>
Date: Wed, 28 Jun 2017 12:22:35 +0200
Subject: [PATCH] Fixed crash executing ""

---
 .../com/mojang/brigadier/CommandDispatcher.java     | 10 +++++++---
 .../com/mojang/brigadier/CommandDispatcherTest.java | 13 +++++++++++++
 2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/src/main/java/com/mojang/brigadier/CommandDispatcher.java b/src/main/java/com/mojang/brigadier/CommandDispatcher.java
index 46d6119..cfec02e 100644
--- a/src/main/java/com/mojang/brigadier/CommandDispatcher.java
+++ b/src/main/java/com/mojang/brigadier/CommandDispatcher.java
@@ -39,9 +39,13 @@ public class CommandDispatcher<S> {
         root.addChild(command.build());
     }
 
-    public int execute(String command, S source) throws CommandException {
-        CommandContext<S> context = parse(command, source).build();
-        return context.getCommand().run(context);
+    public int execute(String input, S source) throws CommandException {
+        CommandContext<S> context = parse(input, source).build();
+        Command<S> command = context.getCommand();
+        if (command == null) {
+            throw ERROR_UNKNOWN_COMMAND.create();
+        }
+        return command.run(context);
     }
 
     public CommandContextBuilder<S> parse(String command, S source) throws CommandException {
diff --git a/src/test/java/com/mojang/brigadier/CommandDispatcherTest.java b/src/test/java/com/mojang/brigadier/CommandDispatcherTest.java
index 07914a8..b704a06 100644
--- a/src/test/java/com/mojang/brigadier/CommandDispatcherTest.java
+++ b/src/test/java/com/mojang/brigadier/CommandDispatcherTest.java
@@ -117,6 +117,19 @@ public class CommandDispatcherTest {
         }
     }
 
+    @Test
+    public void testExecuteEmptyCommand() throws Exception {
+        subject.register(literal(""));
+
+        try {
+            subject.execute("", source);
+            fail();
+        } catch (CommandException ex) {
+            assertThat(ex.getType(), is(CommandDispatcher.ERROR_UNKNOWN_COMMAND));
+            assertThat(ex.getData(), is(Collections.<String, Object>emptyMap()));
+        }
+    }
+
     @Test
     public void testExecuteUnknownSubcommand() throws Exception {
         subject.register(literal("foo").executes(command));