From 60f384f3a00796a2f1fdfa3fc1011cd45372945b Mon Sep 17 00:00:00 2001
From: Moritz Bunkus <moritz@bunkus.org>
Date: Sat, 22 Jul 2017 10:56:04 +0200
Subject: [PATCH] GUI: mux: ensure output name uniqueness before adding to
 queue

Otherwise the following steps would end up overwriting an existing
file:

* add a file
* start multiplexing
* re-use the same settings
* don't change anything regarding files & track selection (but modify
  e.g. a track language)
* start multiplexing again

Fixes #2052.
---
 NEWS.md                          | 3 +++
 src/mkvtoolnix-gui/merge/tab.cpp | 1 +
 2 files changed, 4 insertions(+)

diff --git a/NEWS.md b/NEWS.md
index 47573ea10..8b1a5c13b 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -53,6 +53,9 @@
   again. Fixes #2045.
 * mkvmerge: when appending fails the error message details (e.g. "the number
   of channels differs: 1 and 2") were often not output. Fixes #2046.
+* MKVToolNix GUI: multiplexer: if the GUI is set to ensure unique output file
+  names, it will now verify that right before starting to multiplex/adding the
+  job to the queue, too. Fixes #2052.
 
 ## Build system changes
 
diff --git a/src/mkvtoolnix-gui/merge/tab.cpp b/src/mkvtoolnix-gui/merge/tab.cpp
index 24e5fc871..1ca0787c9 100644
--- a/src/mkvtoolnix-gui/merge/tab.cpp
+++ b/src/mkvtoolnix-gui/merge/tab.cpp
@@ -433,6 +433,7 @@ void
 Tab::addToJobQueue(bool startNow,
                    boost::optional<Util::Settings::ClearMergeSettingsAction> clearSettings) {
   updateConfigFromControlValues();
+  setOutputFileNameMaybe();
 
   if (!isReadyForMerging() || !checkIfOverwritingIsOK())
     return;