gnu: qtdeclarative: Disable QML cache to avoid stale cache issues.

Fixes <https://issues.guix.gnu.org/64605> and similar reports.

* gnu/packages/patches/qtdeclarative-5-disable-qmlcache.patch: New patch.
* gnu/packages/patches/qtdeclarative-disable-qmlcache.patch: Likewise.
* gnu/local.mk (dist_patch_DATA): Register them.
* gnu/packages/qt.scm (qtdeclarative-5, qtdeclarative): Apply them.

Reported-by: Distopico Vegan <distopico@riseup.net>

4 files changed, 38 insertions, 2 deletions

diff --git a/gnu/local.mk b/gnu/local.mk
index 011ababfb7..6e2f70cdaa 100644
--- a/gnu/local.mk
+++ b/gnu/local.mk
@@ -1733,6 +1733,8 @@ dist_patch_DATA =						\
   %D%/packages/patches/python-typeguard-python3.10.patch	\
   %D%/packages/patches/python-w3lib-fix-test-failure.patch	\
   %D%/packages/patches/python-wxwidgets-type-errors.patch	\
+  %D%/packages/patches/qtdeclarative-5-disable-qmlcache.patch	\
+  %D%/packages/patches/qtdeclarative-disable-qmlcache.patch	\
   %D%/packages/patches/quodlibet-fix-invalid-glob.patch	\
   %D%/packages/patches/quodlibet-fix-mtime-tests.patch		\
   %D%/packages/patches/qxlsx-fix-include-directory.patch	\
diff --git a/gnu/packages/patches/qtdeclarative-5-disable-qmlcache.patch b/gnu/packages/patches/qtdeclarative-5-disable-qmlcache.patch
new file mode 100644
index 0000000000..2f1cf0dd4e
--- /dev/null
+++ b/gnu/packages/patches/qtdeclarative-5-disable-qmlcache.patch
@@ -0,0 +1,16 @@
+Retrieved from
+https://github.com/NixOS/nixpkgs/raw/master/pkgs/development/libraries/qt-5/5.15/qtdeclarative-default-disable-qmlcache.patch
+
+diff --git a/src/qml/qml/qqmltypeloader.cpp b/src/qml/qml/qqmltypeloader.cpp
+index 1d66e75..827567a 100644
+--- a/src/qml/qml/qqmltypeloader.cpp
++++ b/src/qml/qml/qqmltypeloader.cpp
+@@ -727,7 +727,7 @@ bool QQmlTypeLoader::Blob::isDebugging() const
+ 
+ bool QQmlTypeLoader::Blob::diskCacheEnabled() const
+ {
+-    return (!disableDiskCache() && !isDebugging()) || forceDiskCache();
++    return forceDiskCache();
+ }
+ 
+ bool QQmlTypeLoader::Blob::qmldirDataAvailable(const QQmlRefPointer<QQmlQmldirData> &data, QList<QQmlError> *errors)
diff --git a/gnu/packages/patches/qtdeclarative-disable-qmlcache.patch b/gnu/packages/patches/qtdeclarative-disable-qmlcache.patch
new file mode 100644
index 0000000000..5f06ec53b4
--- /dev/null
+++ b/gnu/packages/patches/qtdeclarative-disable-qmlcache.patch
@@ -0,0 +1,16 @@
+Retrieved from
+https://raw.githubusercontent.com/NixOS/nixpkgs/master/pkgs/development/libraries/qt-6/patches/qtdeclarative-default-disable-qmlcache.patch
+
+diff --git a/src/qml/jsruntime/qv4engine.cpp b/src/qml/jsruntime/qv4engine.cpp
+index 852cde9e..165f1b57 100644
+--- a/src/qml/jsruntime/qv4engine.cpp
++++ b/src/qml/jsruntime/qv4engine.cpp
+@@ -2093,7 +2093,7 @@ void ExecutionEngine::registerModule(const QString &_name, const QJSValue &modul
+ 
+ bool ExecutionEngine::diskCacheEnabled() const
+ {
+-    return (!disableDiskCache() && !debugger()) || forceDiskCache();
++    return forceDiskCache();
+ }
+ 
+ void ExecutionEngine::callInContext(QV4::Function *function, QObject *self,
diff --git a/gnu/packages/qt.scm b/gnu/packages/qt.scm
index 9708cd6486..e98957ccba 100644
--- a/gnu/packages/qt.scm
+++ b/gnu/packages/qt.scm
@@ -1231,7 +1231,8 @@ xmlpatternsvalidator.")))
               (uri (qt-url name version))
               (sha256
                (base32
-                "1kb8nj17vmnky0ayiwypim7kf6rmlmfcjf6gnrw8rydmp61w0vh2"))))
+                "1kb8nj17vmnky0ayiwypim7kf6rmlmfcjf6gnrw8rydmp61w0vh2"))
+              (patches (search-patches "qtdeclarative-5-disable-qmlcache.patch"))))
     (arguments
      (substitute-keyword-arguments (package-arguments qtsvg-5)
        ((#:tests? _ #f) #f)             ;TODO: Enable the tests
@@ -1277,7 +1278,8 @@ with JavaScript and C++.")))
               (uri (qt-url name version))
               (sha256
                (base32
-                "1hbw63828pp8vm9b46i2pkcbcpr4mq9nblhmpwrw2pflq0fi24xq"))))
+                "1hbw63828pp8vm9b46i2pkcbcpr4mq9nblhmpwrw2pflq0fi24xq"))
+              (patches (search-patches "qtdeclarative-disable-qmlcache.patch"))))
     (build-system cmake-build-system)
     (arguments
      (list