Remove redundant conditions

As mentioned in C++ Core Guidelines ES.87.

src/common/events.h

@@ -39,7 +39,7 @@ class DefaultDataConverter {
                               const int /*index*/,
                               const intptr_t /*value*/,
                               const void* data) {
-        if (data == nullptr) {
+        if (!data) {
             return nullptr;
         }
 
@@ -355,7 +355,7 @@ auto passthrough_event(AEffect* plugin, F callback) {
                 // `effEditOpen()` I can assume there are plugins that don't
                 // handle this correctly.
                 VstRect* editor_rect = *static_cast<VstRect**>(data);
-                if (editor_rect == nullptr) {
+                if (!editor_rect) {
                     return nullptr;
                 }
 
@@ -369,7 +369,7 @@ auto passthrough_event(AEffect* plugin, F callback) {
                 // host doesn't support this.
                 const auto time_info =
                     reinterpret_cast<const VstTimeInfo*>(return_value);
-                if (time_info == nullptr) {
+                if (!time_info) {
                     return nullptr;
                 } else {
                     return *time_info;

src/plugin/configuration.cpp

@@ -50,7 +50,7 @@ Configuration::Configuration(const fs::path& config_path,
 
         // If the table is missing some fields then they will simply be left at
         // their defaults
-        if (toml::table* config = value.as_table(); config != nullptr) {
+        if (toml::table* config = value.as_table()) {
             group = (*config)["group"].value<std::string>();
         }
 

src/wine-host/bridges/vst2.cpp

@@ -58,7 +58,7 @@ uint32_t WINAPI handle_process_replacing_proxy(void*);
 Vst2Bridge& get_bridge_instance(const AEffect* plugin) {
     // This is needed during the initialization of the plugin since we can only
     // add our own pointer after it's done initializing
-    if (current_bridge_instance != nullptr) {
+    if (current_bridge_instance) {
         return *current_bridge_instance;
     }
 
@@ -77,7 +77,7 @@ Vst2Bridge::Vst2Bridge(boost::asio::io_context& main_context,
       host_vst_parameters(io_context),
       host_vst_process_replacing(io_context) {
     // Got to love these C APIs
-    if (plugin_handle == nullptr) {
+    if (!plugin_handle) {
         throw std::runtime_error("Could not load the Windows .dll file at '" +
                                  plugin_dll_path + "'");
     }
@@ -90,11 +90,11 @@ Vst2Bridge::Vst2Bridge(boost::asio::io_context& main_context,
             reinterpret_cast<VstEntryPoint>(reinterpret_cast<size_t>(
                 GetProcAddress(plugin_handle.get(), name)));
 
-        if (vst_entry_point != nullptr) {
+        if (vst_entry_point) {
             break;
         }
     }
-    if (vst_entry_point == nullptr) {
+    if (!vst_entry_point) {
         throw std::runtime_error(
             "Could not find a valid VST entry point for '" + plugin_dll_path +
             "'.");
@@ -116,7 +116,7 @@ Vst2Bridge::Vst2Bridge(boost::asio::io_context& main_context,
         std::lock_guard lock(current_bridge_instance_mutex);
         current_bridge_instance = this;
         plugin = vst_entry_point(host_callback_proxy);
-        if (plugin == nullptr) {
+        if (!plugin) {
             throw std::runtime_error("VST plugin at '" + plugin_dll_path +
                                      "' failed to initialize.");
         }
@@ -301,7 +301,7 @@ void Vst2Bridge::handle_process_replacing() {
                 // Any plugin made in the last fifteen years or so should
                 // support `processReplacing`. In the off chance it does not we
                 // can just emulate this behavior ourselves.
-                if (plugin->processReplacing != nullptr) {
+                if (plugin->processReplacing) {
                     plugin->processReplacing(plugin, inputs.data(),
                                              outputs.data(),
                                              request.sample_frames);

src/wine-host/editor.cpp

@@ -258,7 +258,7 @@ LRESULT CALLBACK window_proc(HWND handle,
                 reinterpret_cast<CREATESTRUCT*>(lParam);
             const auto editor =
                 static_cast<Editor*>(window_parameters->lpCreateParams);
-            if (editor == nullptr) {
+            if (!editor) {
                 break;
             }
 
@@ -272,7 +272,7 @@ LRESULT CALLBACK window_proc(HWND handle,
         case WM_TIMER: {
             auto editor = reinterpret_cast<Editor*>(
                 GetWindowLongPtr(handle, GWLP_USERDATA));
-            if (editor == nullptr || wParam != idle_timer_id) {
+            if (!editor || wParam != idle_timer_id) {
                 break;
             }