core: add CacheDir pragma

Closes #293

changelog/next.md

@@ -2,6 +2,7 @@
 
 - Added support for creating wayland idle inhibitors.
 - Added support for wayland idle timeouts.
+- Added the ability to override Quickshell.cacheDir with a custom path.
 
 ## Bug Fixes
 

src/core/paths.cpp

@@ -27,12 +27,19 @@ QsPaths* QsPaths::instance() {
 	return instance;
 }
 
-void QsPaths::init(QString shellId, QString pathId, QString dataOverride, QString stateOverride) {
+void QsPaths::init(
+    QString shellId,
+    QString pathId,
+    QString dataOverride,
+    QString stateOverride,
+    QString cacheOverride
+) {
 	auto* instance = QsPaths::instance();
 	instance->shellId = std::move(shellId);
 	instance->pathId = std::move(pathId);
 	instance->shellDataOverride = std::move(dataOverride);
 	instance->shellStateOverride = std::move(stateOverride);
+	instance->shellCacheOverride = std::move(cacheOverride);
 }
 
 QDir QsPaths::crashDir(const QString& id) {
@@ -316,9 +323,16 @@ QDir QsPaths::shellStateDir() {
 
 QDir QsPaths::shellCacheDir() {
 	if (this->shellCacheState == DirState::Unknown) {
-		auto dir = QDir(QStandardPaths::writableLocation(QStandardPaths::CacheLocation));
-		dir = QDir(dir.filePath("by-shell"));
-		dir = QDir(dir.filePath(this->shellId));
+		QDir dir;
+		if (this->shellCacheOverride.isEmpty()) {
+			dir = QDir(QStandardPaths::writableLocation(QStandardPaths::CacheLocation));
+			dir = QDir(dir.filePath("by-shell"));
+			dir = QDir(dir.filePath(this->shellId));
+		} else {
+			auto basedir = QStandardPaths::writableLocation(QStandardPaths::GenericCacheLocation);
+			dir = QDir(this->shellCacheOverride.replace("$BASE", basedir));
+		}
+
 		this->mShellCacheDir = dir;
 
 		qCDebug(logPaths) << "Initialized cache path:" << dir.path();

src/core/paths.hpp

@@ -17,7 +17,13 @@ QDataStream& operator>>(QDataStream& stream, InstanceLockInfo& info);
 class QsPaths {
 public:
 	static QsPaths* instance();
-	static void init(QString shellId, QString pathId, QString dataOverride, QString stateOverride);
+	static void init(
+	    QString shellId,
+	    QString pathId,
+	    QString dataOverride,
+	    QString stateOverride,
+	    QString cacheOverride
+	);
 	static QDir crashDir(const QString& id);
 	static QString basePath(const QString& id);
 	static QString ipcPath(const QString& id);
@@ -65,4 +71,5 @@ private:
 
 	QString shellDataOverride;
 	QString shellStateOverride;
+	QString shellCacheOverride;
 };

src/core/qmlglobal.hpp

@@ -127,18 +127,21 @@ class QuickshellGlobal: public QObject {
 	/// Usually `~/.local/share/quickshell/by-shell/<shell-id>`
 	///
 	/// Can be overridden using `//@ pragma DataDir $BASE/path` in the root qml file, where `$BASE`
-	/// corrosponds to `$XDG_DATA_HOME` (usually `~/.local/share`).
+	/// corresponds to `$XDG_DATA_HOME` (usually `~/.local/share`).
 	Q_PROPERTY(QString dataDir READ dataDir CONSTANT);
 	/// The per-shell state directory.
 	///
 	/// Usually `~/.local/state/quickshell/by-shell/<shell-id>`
 	///
 	/// Can be overridden using `//@ pragma StateDir $BASE/path` in the root qml file, where `$BASE`
-	/// corrosponds to `$XDG_STATE_HOME` (usually `~/.local/state`).
+	/// corresponds to `$XDG_STATE_HOME` (usually `~/.local/state`).
 	Q_PROPERTY(QString stateDir READ stateDir CONSTANT);
 	/// The per-shell cache directory.
 	///
 	/// Usually `~/.cache/quickshell/by-shell/<shell-id>`
+	///
+	/// Can be overridden using `//@ pragma CacheDir $BASE/path` in the root qml file, where `$BASE`
+	/// corresponds to `$XDG_CACHE_HOME` (usually `~/.cache`).
 	Q_PROPERTY(QString cacheDir READ cacheDir CONSTANT);
 	// clang-format on
 	QML_SINGLETON;

src/launch/launch.cpp

@@ -78,6 +78,7 @@ int launch(const LaunchArgs& args, char** argv, QCoreApplication* coreApplicatio
 		QHash<QString, QString> envOverrides;
 		QString dataDir;
 		QString stateDir;
+		QString cacheDir;
 	} pragmas;
 
 	auto stream = QTextStream(&file);
@@ -109,6 +110,8 @@ int launch(const LaunchArgs& args, char** argv, QCoreApplication* coreApplicatio
 				pragmas.dataDir = pragma.sliced(8).trimmed();
 			} else if (pragma.startsWith("StateDir ")) {
 				pragmas.stateDir = pragma.sliced(9).trimmed();
+			} else if (pragma.startsWith("CacheDir ")) {
+				pragmas.cacheDir = pragma.sliced(9).trimmed();
 			} else {
 				qCritical() << "Unrecognized pragma" << pragma;
 				return -1;
@@ -150,7 +153,7 @@ int launch(const LaunchArgs& args, char** argv, QCoreApplication* coreApplicatio
 	}
 #endif
 
-	QsPaths::init(shellId, pathId, pragmas.dataDir, pragmas.stateDir);
+	QsPaths::init(shellId, pathId, pragmas.dataDir, pragmas.stateDir, pragmas.cacheDir);
 	QsPaths::instance()->linkRunDir();
 	QsPaths::instance()->linkPathDir();
 	LogManager::initFs();