5 files changed, 55 insertions, 1 deletions

diff --git a/src/ClientHandle.cpp b/src/ClientHandle.cpp
index 772d8ad6c..997510684 100644
--- a/src/ClientHandle.cpp
+++ b/src/ClientHandle.cpp
@@ -1831,12 +1831,24 @@ void cClientHandle::HandleUnmount(void)
 void cClientHandle::HandleTabCompletion(const AString & a_Text)
 {
 	AStringVector Results;
-	m_Player->GetWorld()->TabCompleteUserName(a_Text, Results);
+	// Get player name completions.
+	if (cRoot::Get()->GetServer()->ShouldAllowMultiWorldTabCompletion())
+	{
+		Results = cRoot::Get()->GetPlayerTabCompletionMultiWorld(a_Text);
+	}
+	else
+	{
+		m_Player->GetWorld()->TabCompleteUserName(a_Text, Results);
+	}
+
+	// Get command completions.
 	cRoot::Get()->GetPluginManager()->TabCompleteCommand(a_Text, Results, m_Player);
 	if (Results.empty())
 	{
 		return;
 	}
+
+	// Sort and send results.
 	std::sort(Results.begin(), Results.end());
 	SendTabCompletionResults(Results);
 }
diff --git a/src/Root.cpp b/src/Root.cpp
index 1eca73cb2..09c91bc72 100644
--- a/src/Root.cpp
+++ b/src/Root.cpp
@@ -1006,3 +1006,33 @@ int cRoot::GetFurnaceFuelBurnTime(const cItem & a_Fuel)
 	cFurnaceRecipe * FR = Get()->GetFurnaceRecipe();
 	return FR->GetBurnTime(a_Fuel);
 }
+
+
+
+
+
+AStringVector cRoot::GetPlayerTabCompletionMultiWorld(const AString & a_Text)
+{
+	AStringVector Results;
+	class cWorldCallback : public cWorldListCallback
+	{
+	public:
+		cWorldCallback(AStringVector & a_Results, const AString & a_Search) :
+			m_Results(a_Results),
+			m_Search(a_Search)
+		{
+		}
+
+		virtual bool Item(cWorld * a_World) override
+		{
+			a_World->TabCompleteUserName(m_Search, m_Results);
+			return true;
+		}
+	private:
+		AStringVector & m_Results;
+		const AString & m_Search;
+	} WC(Results, a_Text);
+
+	Get()->ForEachWorld(WC);
+	return Results;
+}
diff --git a/src/Root.h b/src/Root.h
index a828dc3fa..722554332 100644
--- a/src/Root.h
+++ b/src/Root.h
@@ -89,6 +89,10 @@ public:
 	/** Returns the number of ticks for how long the item would fuel a furnace. Returns zero if not a fuel */
 	static int GetFurnaceFuelBurnTime(const cItem & a_Fuel);  // tolua_export
 
+	/** Returns the completions for a player name across all worlds. Returns an
+	empty vector if none are found. */
+	AStringVector GetPlayerTabCompletionMultiWorld(const AString & a_Text);
+
 	/** The current time where the startup of the server has been completed */
 	std::chrono::steady_clock::time_point m_StartTime;
 
diff --git a/src/Server.cpp b/src/Server.cpp
index 8405109de..ba469bd3e 100644
--- a/src/Server.cpp
+++ b/src/Server.cpp
@@ -234,6 +234,7 @@ bool cServer::InitServer(cSettingsRepositoryInterface & a_Settings, bool a_Shoul
 		LOGWARNING("WARNING: BungeeCord is allowed and server set to online mode. This is unsafe and will not work properly. Disable either authentication or BungeeCord in settings.ini.");
 	}
 
+	m_ShouldAllowMultiWorldTabCompletion = a_Settings.GetValueSetB("Server", "AllowMultiWorldTabCompletion", true);
 	m_ShouldLoadOfflinePlayerData = a_Settings.GetValueSetB("PlayerData", "LoadOfflinePlayerData", false);
 	m_ShouldLoadNamedPlayerData   = a_Settings.GetValueSetB("PlayerData", "LoadNamedPlayerData", true);
 
diff --git a/src/Server.h b/src/Server.h
index b6c8bfe1f..600e7ca97 100644
--- a/src/Server.h
+++ b/src/Server.h
@@ -139,6 +139,10 @@ public:
 	it makes the server vulnerable to identity theft through direct connections. */
 	bool ShouldAllowBungeeCord(void) const { return m_ShouldAllowBungeeCord; }
 
+	/** Returns true if usernames should be completed across worlds. This is read
+	from the settings. */
+	bool ShouldAllowMultiWorldTabCompletion(void) const { return m_ShouldAllowMultiWorldTabCompletion; }
+
 private:
 
 	friend class cRoot;  // so cRoot can create and destroy cServer
@@ -230,6 +234,9 @@ private:
 	/** True if BungeeCord handshake packets (with player UUID) should be accepted. */
 	bool m_ShouldAllowBungeeCord;
 
+	/** True if usernames should be completed across worlds. */
+	bool m_ShouldAllowMultiWorldTabCompletion;
+
 	/** The list of ports on which the server should listen for connections.
 	Initialized in InitServer(), used in Start(). */
 	AStringVector m_Ports;