core: add --verify-config to verify the config with Hyprland

fixes #9135

7 files changed, 69 insertions, 25 deletions

diff --git a/src/Compositor.cpp b/src/Compositor.cpp
index cb0665e5..ab9c16f7 100644
--- a/src/Compositor.cpp
+++ b/src/Compositor.cpp
@@ -22,6 +22,7 @@
 #include <cstring>
 #include <filesystem>
 #include <ranges>
+#include <print>
 #include <unordered_set>
 #include "debug/HyprCtl.hpp"
 #include "debug/CrashReporter.hpp"
@@ -162,7 +163,10 @@ void CCompositor::restoreNofile() {
         Debug::log(ERR, "Failed restoring NOFILE limits");
 }
 
-CCompositor::CCompositor() : m_iHyprlandPID(getpid()) {
+CCompositor::CCompositor(bool onlyConfig) : m_bOnlyConfigVerification(onlyConfig), m_iHyprlandPID(getpid()) {
+    if (onlyConfig)
+        return;
+
     m_szHyprTempDataRoot = std::string{getenv("XDG_RUNTIME_DIR")} + "/hypr";
 
     if (m_szHyprTempDataRoot.starts_with("/hypr")) {
@@ -226,7 +230,7 @@ CCompositor::CCompositor() : m_iHyprlandPID(getpid()) {
 }
 
 CCompositor::~CCompositor() {
-    if (!m_bIsShuttingDown)
+    if (!m_bIsShuttingDown && !m_bOnlyConfigVerification)
         cleanup();
 }
 
@@ -262,6 +266,16 @@ static bool filterGlobals(const wl_client* client, const wl_global* global, void
 //
 void CCompositor::initServer(std::string socketName, int socketFd) {
 
+    if (m_bOnlyConfigVerification) {
+        g_pHookSystem       = makeUnique<CHookSystemManager>();
+        g_pKeybindManager   = makeUnique<CKeybindManager>();
+        g_pAnimationManager = makeUnique<CHyprAnimationManager>();
+        g_pConfigManager    = makeUnique<CConfigManager>();
+
+        std::println("\n\n======== Config parsing result:\n\n{}", g_pConfigManager->verify());
+        return;
+    }
+
     m_sWLDisplay = wl_display_create();
 
     wl_display_set_global_filter(m_sWLDisplay, ::filterGlobals, nullptr);
diff --git a/src/Compositor.hpp b/src/Compositor.hpp
index f2e2ca14..295878df 100644
--- a/src/Compositor.hpp
+++ b/src/Compositor.hpp
@@ -24,7 +24,7 @@ enum eManagersInitStage : uint8_t {
 
 class CCompositor {
   public:
-    CCompositor();
+    CCompositor(bool onlyConfig = false);
     ~CCompositor();
 
     wl_display*                                m_sWLDisplay;
@@ -71,10 +71,11 @@ class CCompositor {
     bool                                       m_bUnsafeState    = false; // unsafe state is when there is no monitors.
     bool                                       m_bNextIsUnsafe   = false;
     PHLMONITORREF                              m_pUnsafeOutput; // fallback output for the unsafe state
-    bool                                       m_bIsShuttingDown = false;
-    bool                                       m_bFinalRequests  = false;
-    bool                                       m_bDesktopEnvSet  = false;
-    bool                                       m_bWantsXwayland  = true;
+    bool                                       m_bIsShuttingDown         = false;
+    bool                                       m_bFinalRequests          = false;
+    bool                                       m_bDesktopEnvSet          = false;
+    bool                                       m_bWantsXwayland          = true;
+    bool                                       m_bOnlyConfigVerification = false;
 
     // ------------------------------------------------- //
 
diff --git a/src/config/ConfigManager.cpp b/src/config/ConfigManager.cpp
index f5c9b3ee..c5d70329 100644
--- a/src/config/ConfigManager.cpp
+++ b/src/config/ConfigManager.cpp
@@ -19,6 +19,7 @@
 #include "../render/Renderer.hpp"
 #include "../hyprerror/HyprError.hpp"
 #include "../managers/input/InputManager.hpp"
+#include "../managers/eventLoop/EventLoopManager.hpp"
 #include "../managers/LayoutManager.hpp"
 #include "../managers/EventManager.hpp"
 #include "../debug/HyprNotificationOverlay.hpp"
@@ -730,15 +731,18 @@ CConfigManager::CConfigManager() {
 
     resetHLConfig();
 
-    Debug::log(INFO,
-               "!!!!HEY YOU, YES YOU!!!!: further logs to stdout / logfile are disabled by default. BEFORE SENDING THIS LOG, ENABLE THEM. Use debug:disable_logs = false to do so: "
-               "https://wiki.hyprland.org/Configuring/Variables/#debug");
+    if (!g_pCompositor->m_bOnlyConfigVerification) {
+        Debug::log(
+            INFO,
+            "!!!!HEY YOU, YES YOU!!!!: further logs to stdout / logfile are disabled by default. BEFORE SENDING THIS LOG, ENABLE THEM. Use debug:disable_logs = false to do so: "
+            "https://wiki.hyprland.org/Configuring/Variables/#debug");
+    }
 
     Debug::disableLogs = reinterpret_cast<int64_t* const*>(m_pConfig->getConfigValuePtr("debug:disable_logs")->getDataStaticPtr());
     Debug::disableTime = reinterpret_cast<int64_t* const*>(m_pConfig->getConfigValuePtr("debug:disable_time")->getDataStaticPtr());
 
-    if (ERR.has_value())
-        g_pHyprError->queueCreate(ERR.value(), CHyprColor{1.0, 0.1, 0.1, 1.0});
+    if (g_pEventLoopManager && ERR.has_value())
+        g_pEventLoopManager->doLater([ERR] { g_pHyprError->queueCreate(ERR.value(), CHyprColor{1.0, 0.1, 0.1, 1.0}); });
 }
 
 std::optional<std::string> CConfigManager::generateConfig(std::string configPath) {
@@ -820,11 +824,23 @@ void CConfigManager::reload() {
     EMIT_HOOK_EVENT("preConfigReload", nullptr);
     setDefaultAnimationVars();
     resetHLConfig();
-    configCurrentPath = getMainConfigPath();
-    const auto ERR    = m_pConfig->parse();
+    configCurrentPath                      = getMainConfigPath();
+    const auto ERR                         = m_pConfig->parse();
+    m_bLastConfigVerificationWasSuccessful = !ERR.error;
     postConfigReload(ERR);
 }
 
+std::string CConfigManager::verify() {
+    setDefaultAnimationVars();
+    resetHLConfig();
+    configCurrentPath                      = getMainConfigPath();
+    const auto ERR                         = m_pConfig->parse();
+    m_bLastConfigVerificationWasSuccessful = !ERR.error;
+    if (ERR.error)
+        return ERR.getError();
+    return "config ok";
+}
+
 void CConfigManager::setDefaultAnimationVars() {
     m_AnimationTree.createNode("__internal_fadeCTM");
     m_AnimationTree.createNode("global");
diff --git a/src/config/ConfigManager.hpp b/src/config/ConfigManager.hpp
index 31ad81cd..564c1ebf 100644
--- a/src/config/ConfigManager.hpp
+++ b/src/config/ConfigManager.hpp
@@ -144,6 +144,7 @@ class CConfigManager {
 
     void                                                            init();
     void                                                            reload();
+    std::string                                                     verify();
 
     int                                                             getDeviceInt(const std::string&, const std::string&, const std::string& fallback = "");
     float                                                           getDeviceFloat(const std::string&, const std::string&, const std::string& fallback = "");
@@ -257,9 +258,10 @@ class CConfigManager {
         {"scrollmouse", [](const PHLWINDOW& pWindow) { return &pWindow->m_sWindowData.scrollMouse; }},
         {"scrolltouchpad", [](const PHLWINDOW& pWindow) { return &pWindow->m_sWindowData.scrollTouchpad; }}};
 
-    bool m_bWantsMonitorReload = false;
-    bool m_bNoMonitorReload    = false;
-    bool isLaunchingExecOnce   = false; // For exec-once to skip initial ws tracking
+    bool m_bWantsMonitorReload                  = false;
+    bool m_bNoMonitorReload                     = false;
+    bool isLaunchingExecOnce                    = false; // For exec-once to skip initial ws tracking
+    bool m_bLastConfigVerificationWasSuccessful = true;
 
   private:
     UP<Hyprlang::CConfig>                            m_pConfig;
diff --git a/src/main.cpp b/src/main.cpp
index bb5e5622..d244f10f 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -27,6 +27,7 @@ static void help() {
     --wayland-fd FD              - Sets the Wayland socket fd (for Wayland socket handover)
     --systeminfo                 - Prints system infos
     --i-am-really-stupid         - Omits root user privileges check (why would you do that?)
+    --verify-config              - Do not run Hyprland, only print if the config has any errors
     --version           -v       - Print this binary's version)");
 }
 
@@ -49,7 +50,7 @@ int main(int argc, char** argv) {
     std::string              configPath;
     std::string              socketName;
     int                      socketFd   = -1;
-    bool                     ignoreSudo = false;
+    bool                     ignoreSudo = false, verifyConfig = false;
 
     std::vector<std::string> args{argv + 1, argv + argc};
 
@@ -124,6 +125,9 @@ int main(int argc, char** argv) {
         } else if (*it == "--systeminfo") {
             std::println("{}", systemInfoRequest(eHyprCtlOutputFormat::FORMAT_NORMAL, ""));
             return 0;
+        } else if (*it == "--verify-config") {
+            verifyConfig = true;
+            continue;
         } else {
             std::println(stderr, "[ ERROR ] Unknown option '{}' !", *it);
             help();
@@ -138,9 +142,8 @@ int main(int argc, char** argv) {
                      "          Hint: Use the --i-am-really-stupid flag to omit that check.");
 
         return 1;
-    } else if (ignoreSudo && NInit::isSudo()) {
+    } else if (ignoreSudo && NInit::isSudo())
         std::println("Superuser privileges check is omitted. I hope you know what you're doing.");
-    }
 
     if (socketName.empty() ^ (socketFd == -1)) {
         std::println(stderr,
@@ -150,12 +153,13 @@ int main(int argc, char** argv) {
         return 1;
     }
 
-    std::println("Welcome to Hyprland!");
+    if (!verifyConfig)
+        std::println("Welcome to Hyprland!");
 
     // let's init the compositor.
     // it initializes basic Wayland stuff in the constructor.
     try {
-        g_pCompositor                     = makeUnique<CCompositor>();
+        g_pCompositor                     = makeUnique<CCompositor>(verifyConfig);
         g_pCompositor->explicitConfigPath = configPath;
     } catch (const std::exception& e) {
         std::println(stderr, "Hyprland threw in ctor: {}\nCannot continue.", e.what());
@@ -164,6 +168,9 @@ int main(int argc, char** argv) {
 
     g_pCompositor->initServer(socketName, socketFd);
 
+    if (verifyConfig)
+        return !g_pConfigManager->m_bLastConfigVerificationWasSuccessful;
+
     if (!envEnabled("HYPRLAND_NO_RT"))
         NInit::gainRealTime();
 
diff --git a/src/managers/AnimationManager.cpp b/src/managers/AnimationManager.cpp
index f884acdd..964f7cfa 100644
--- a/src/managers/AnimationManager.cpp
+++ b/src/managers/AnimationManager.cpp
@@ -34,7 +34,8 @@ static int wlTick(SP<CEventLoopTimer> self, void* data) {
 
 CHyprAnimationManager::CHyprAnimationManager() {
     m_pAnimationTimer = SP<CEventLoopTimer>(new CEventLoopTimer(std::chrono::microseconds(500), wlTick, nullptr));
-    g_pEventLoopManager->addTimer(m_pAnimationTimer);
+    if (g_pEventLoopManager) // null in --verify-config mode
+        g_pEventLoopManager->addTimer(m_pAnimationTimer);
 
     addBezierWithName("linear", Vector2D(0.0, 0.0), Vector2D(1.0, 1.0));
 }
diff --git a/src/managers/KeybindManager.cpp b/src/managers/KeybindManager.cpp
index 4706c1e1..e2191bc6 100644
--- a/src/managers/KeybindManager.cpp
+++ b/src/managers/KeybindManager.cpp
@@ -172,8 +172,11 @@ CKeybindManager::CKeybindManager() {
         },
         nullptr);
 
-    g_pEventLoopManager->addTimer(m_pLongPressTimer);
-    g_pEventLoopManager->addTimer(m_pRepeatKeyTimer);
+    // null in --verify-config mode
+    if (g_pEventLoopManager) {
+        g_pEventLoopManager->addTimer(m_pLongPressTimer);
+        g_pEventLoopManager->addTimer(m_pRepeatKeyTimer);
+    }
 
     static auto P = g_pHookSystem->hookDynamic("configReloaded", [this](void* hk, SCallbackInfo& info, std::any param) {
         // clear cuz realloc'd