macOS: Fix option as alt not working for keys that act as dead keys in the current keyboard layout

glfw/cocoa_platform.h

@@ -37,6 +37,7 @@ typedef void* id;
 #endif
 
 typedef VkFlags VkMacOSSurfaceCreateFlagsMVK;
+typedef int (* GLFWcocoatextinputfilterfun)(int,int,int);
 
 typedef struct VkMacOSSurfaceCreateInfoMVK
 {
@@ -98,6 +99,8 @@ typedef struct _GLFWwindowNS
     // This is kept to counteract Cocoa doing the same internally
     double          cursorWarpDeltaX, cursorWarpDeltaY;
 
+    // The text input filter callback
+    GLFWcocoatextinputfilterfun textInputFilterCallback;
 } _GLFWwindowNS;
 
 // Cocoa-specific global data

glfw/cocoa_window.m

@@ -725,10 +725,12 @@ - (void)keyDown:(NSEvent *)event
     const int key = translateKey(scancode, GLFW_TRUE);
     const int mods = translateFlags([event modifierFlags]);
     _glfw.ns.text[0] = 0;
-    // this will call insertText with the text for this event, if any
-    [self interpretKeyEvents:[NSArray arrayWithObject:event]];
-    if ((1 <= _glfw.ns.text[0] && _glfw.ns.text[0] <= 31) || (unsigned)_glfw.ns.text[0] == 127) _glfw.ns.text[0] = 0;  // dont send text for ascii control codes
-    debug_key(@"scancode: 0x%x (%s) mods: %stext: %s glfw_key: %s\n",
+    if (!window->ns.textInputFilterCallback || window->ns.textInputFilterCallback(key, mods, scancode) != 1) {
+        // this will call insertText with the text for this event, if any
+        [self interpretKeyEvents:[NSArray arrayWithObject:event]];
+        if ((1 <= _glfw.ns.text[0] && _glfw.ns.text[0] <= 31) || (unsigned)_glfw.ns.text[0] == 127) _glfw.ns.text[0] = 0;  // dont send text for ascii control codes
+    }
+    debug_key(@"scancode: 0x%x (%s)%stext: %s glfw_key: %s\n",
             scancode, safe_name_for_scancode(scancode), format_mods(mods),
             format_text(_glfw.ns.text), _glfwGetKeyName(key));
     _glfwInputKeyboard(window, key, scancode, GLFW_PRESS, mods, _glfw.ns.text, 0);
@@ -2000,3 +2002,11 @@ GLFWAPI id glfwGetCocoaWindow(GLFWwindow* handle)
     _GLFW_REQUIRE_INIT_OR_RETURN(nil);
     return window->ns.object;
 }
+
+GLFWAPI GLFWcocoatextinputfilterfun glfwSetCocoaTextInputFilter(GLFWwindow *handle, GLFWcocoatextinputfilterfun callback) {
+    _GLFWwindow* window = (_GLFWwindow*) handle;
+    _GLFW_REQUIRE_INIT_OR_RETURN(nil);
+    GLFWcocoatextinputfilterfun previous = window->ns.textInputFilterCallback;
+    window->ns.textInputFilterCallback = callback;
+    return previous;
+}

glfw/glfw.py

@@ -196,6 +196,7 @@ def generate_wrappers(glfw_header, glfw_native_header):
     for line in '''\
     void* glfwGetCocoaWindow(GLFWwindow* window)
     uint32_t glfwGetCocoaMonitor(GLFWmonitor* monitor)
+    GLFWcocoatextinputfilterfun glfwSetCocoaTextInputFilter(GLFWwindow* window, GLFWcocoatextinputfilterfun callback)
     void* glfwGetX11Display(void)
     int32_t glfwGetX11Window(GLFWwindow* window)
     void glfwSetX11SelectionString(const char* string)
@@ -212,6 +213,7 @@ def generate_wrappers(glfw_header, glfw_native_header):
 #pragma once
 #include <stddef.h>
 #include <stdint.h>
+typedef int (* GLFWcocoatextinputfilterfun)(int,int,unsigned int);
 {}
 
 {}

kitty/glfw-wrapper.c

@@ -357,6 +357,8 @@ load_glfw(const char* path) {
 
     *(void **) (&glfwGetCocoaMonitor_impl) = dlsym(handle, "glfwGetCocoaMonitor");
 
+    *(void **) (&glfwSetCocoaTextInputFilter_impl) = dlsym(handle, "glfwSetCocoaTextInputFilter");
+
     *(void **) (&glfwGetX11Display_impl) = dlsym(handle, "glfwGetX11Display");
 
     *(void **) (&glfwGetX11Window_impl) = dlsym(handle, "glfwGetX11Window");

kitty/glfw-wrapper.h

@@ -1,6 +1,7 @@
 #pragma once
 #include <stddef.h>
 #include <stdint.h>
+typedef int (* GLFWcocoatextinputfilterfun)(int,int,unsigned int);
 
 
 /*! @name GLFW version macros
@@ -1825,6 +1826,10 @@ typedef uint32_t (*glfwGetCocoaMonitor_func)(GLFWmonitor*);
 glfwGetCocoaMonitor_func glfwGetCocoaMonitor_impl;
 #define glfwGetCocoaMonitor glfwGetCocoaMonitor_impl
 
+typedef GLFWcocoatextinputfilterfun (*glfwSetCocoaTextInputFilter_func)(GLFWwindow*, GLFWcocoatextinputfilterfun);
+glfwSetCocoaTextInputFilter_func glfwSetCocoaTextInputFilter_impl;
+#define glfwSetCocoaTextInputFilter glfwSetCocoaTextInputFilter_impl
+
 typedef void* (*glfwGetX11Display_func)();
 glfwGetX11Display_func glfwGetX11Display_impl;
 #define glfwGetX11Display glfwGetX11Display_impl

kitty/glfw.c

@@ -309,6 +309,13 @@ set_dpi_from_os_window(OSWindow *w) {
 
 static bool is_first_window = true;
 
+#ifdef __APPLE__
+static int
+filter_option(int key UNUSED, int mods, unsigned int scancode UNUSED) {
+    return ((mods == GLFW_MOD_ALT) || (mods == (GLFW_MOD_ALT | GLFW_MOD_SHIFT))) ? 1 : 0;
+}
+#endif
+
 static PyObject*
 create_os_window(PyObject UNUSED *self, PyObject *args) {
     int width, height, x = -1, y = -1;
@@ -367,6 +374,7 @@ create_os_window(PyObject UNUSED *self, PyObject *args) {
         Py_DECREF(ret);
 #ifdef __APPLE__
         cocoa_create_global_menu();
+        if (OPT(macos_option_as_alt)) glfwSetCocoaTextInputFilter(glfw_window, filter_option);
 #endif
         is_first_window = false;
     }

kitty/keys.c

@@ -43,22 +43,6 @@ active_window() {
     return NULL;
 }
 
-void
-on_text_input(unsigned int codepoint, int mods) {
-    Window *w = active_window();
-    static char buf[16];
-    unsigned int sz = 0;
-
-    if (w != NULL) {
-        bool is_text = mods <= GLFW_MOD_SHIFT;
-        if (is_text) sz = encode_utf8(codepoint, buf);
-#ifdef __APPLE__
-        if (!OPT(macos_option_as_alt) && IS_ALT_MODS(mods)) sz = encode_utf8(codepoint, buf);
-#endif
-        if (sz) schedule_write_to_child(w->id, buf, sz);
-    }
-}
-
 static inline bool
 is_modifier_key(int key) {
     switch(key) {
@@ -107,9 +91,6 @@ on_key_input(int key, int scancode, int action, int mods, const char* text, int
     }
     Screen *screen = w->render_data.screen;
     bool has_text = text && !is_ascii_control_char(text[0]);
-#ifdef __APPLE__
-    if (has_text && IS_ALT_MODS(mods) && OPT(macos_option_as_alt)) has_text = false;
-#endif
     if (action == GLFW_PRESS || action == GLFW_REPEAT) {
         uint16_t qkey = (0 <= key && key < (ssize_t)arraysz(key_map)) ? key_map[key] : UINT8_MAX;
         bool special = false;