From c59c91ec93c44586676437bf97f1fd4c18d34ffe Mon Sep 17 00:00:00 2001
From: Be <be@mixxx.org>
Date: Sun, 14 Jun 2020 15:26:53 -0500
Subject: [PATCH] ControllerEngine: reload JS module when the file changes

This only applies to the JS module loaded from the XML file. JS files
loaded from that via the JS `import` keyword are not reloaded unless the
module file loaded by the XML file is changed.
---
 src/controllers/engine/controllerengine.cpp | 10 ++++++++++
 src/controllers/engine/controllerengine.h   |  1 +
 2 files changed, 11 insertions(+)

diff --git a/src/controllers/engine/controllerengine.cpp b/src/controllers/engine/controllerengine.cpp
index 890a48fd82f3..b7491ed2c745 100644
--- a/src/controllers/engine/controllerengine.cpp
+++ b/src/controllers/engine/controllerengine.cpp
@@ -228,11 +228,20 @@ void ControllerEngine::uninitializeScriptEngine() {
 }
 
 void ControllerEngine::loadModule(QFileInfo moduleFileInfo) {
+    m_moduleFileInfo = moduleFileInfo;
+
     QJSValue mod = m_pScriptEngine->importModule(moduleFileInfo.absoluteFilePath());
     if (mod.isError()) {
         showScriptExceptionDialog(mod);
         return;
     }
+
+    connect(&m_scriptWatcher,
+            &QFileSystemWatcher::fileChanged,
+            this,
+            &ControllerEngine::scriptHasChanged);
+    m_scriptWatcher.addPath(moduleFileInfo.absoluteFilePath());
+
     QJSValue initFunction = mod.property("init");
     if (initFunction.isCallable()) {
         initFunction.call();
@@ -307,6 +316,7 @@ void ControllerEngine::reloadScripts() {
 
     qDebug() << "Re-initializing scripts";
     initializeScripts(m_lastScriptFiles);
+    loadModule(m_moduleFileInfo);
 }
 
 void ControllerEngine::initializeScripts(const QList<ControllerPreset::ScriptFileInfo>& scripts) {
diff --git a/src/controllers/engine/controllerengine.h b/src/controllers/engine/controllerengine.h
index 46bacbb5ca75..42ac2cba912e 100644
--- a/src/controllers/engine/controllerengine.h
+++ b/src/controllers/engine/controllerengine.h
@@ -171,6 +171,7 @@ class ControllerEngine : public QObject {
     QJSValue m_byteArrayToScriptValueJSFunction;
     // Filesystem watcher for script auto-reload
     QFileSystemWatcher m_scriptWatcher;
+    QFileInfo m_moduleFileInfo;
     QList<ControllerPreset::ScriptFileInfo> m_lastScriptFiles;
 
     bool m_bTesting;