From aa621021e293652093b8b64fd0aaa2805dffa5e6 Mon Sep 17 00:00:00 2001
From: NitrinCloud <113344017+NitrinCloud@users.noreply.github.com>
Date: Sat, 7 Jan 2023 08:39:32 +0100
Subject: [PATCH] Support dynamic selection of a port using '0' (#1661)

---
 .../minestom/server/network/socket/Server.java    |  4 ++++
 .../server/network/socket/ServerAddressTest.java  | 15 ++++++++++++++-
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/src/main/java/net/minestom/server/network/socket/Server.java b/src/main/java/net/minestom/server/network/socket/Server.java
index 68f0189e4..88dd5393e 100644
--- a/src/main/java/net/minestom/server/network/socket/Server.java
+++ b/src/main/java/net/minestom/server/network/socket/Server.java
@@ -63,6 +63,10 @@ public final class Server {
         server.register(selector, SelectionKey.OP_ACCEPT);
         this.serverSocket = server;
         this.socketAddress = address;
+
+        if (address instanceof InetSocketAddress && port == 0) {
+            port = server.socket().getLocalPort();
+        }
     }
 
     @ApiStatus.Internal
diff --git a/src/test/java/net/minestom/server/network/socket/ServerAddressTest.java b/src/test/java/net/minestom/server/network/socket/ServerAddressTest.java
index 931fb9600..1836cf2b6 100644
--- a/src/test/java/net/minestom/server/network/socket/ServerAddressTest.java
+++ b/src/test/java/net/minestom/server/network/socket/ServerAddressTest.java
@@ -14,7 +14,7 @@ public class ServerAddressTest {
 
     @Test
     public void inetAddressTest() throws IOException {
-        InetSocketAddress address = new InetSocketAddress("localhost", 0);
+        InetSocketAddress address = new InetSocketAddress("localhost", 25565);
         var server = new Server(new PacketProcessor());
         server.init(address);
         assertSame(address, server.socketAddress());
@@ -25,6 +25,19 @@ public class ServerAddressTest {
         assertDoesNotThrow(server::stop);
     }
 
+    @Test
+    public void inetAddressDynamicTest() throws IOException {
+        InetSocketAddress address = new InetSocketAddress("localhost", 0);
+        var server = new Server(new PacketProcessor());
+        server.init(address);
+        assertSame(address, server.socketAddress());
+        assertEquals(address.getHostString(), server.getAddress());
+        assertNotEquals(address.getPort(), server.getPort());
+
+        assertDoesNotThrow(server::start);
+        assertDoesNotThrow(server::stop);
+    }
+
     @Test
     public void unixAddressTest() throws IOException {
         UnixDomainSocketAddress address = UnixDomainSocketAddress.of("minestom.sock");