macOS: Use the system cursor blink interval by default

Can be changed with:

defaults write -g NSTextInsertionPointBlinkPeriodOff -float 500
defaults write -g NSTextInsertionPointBlinkPeriodOn -float 500

docs/changelog.rst

@@ -66,6 +66,10 @@ To update |kitty|, :doc:`follow the instructions <binary>`.
 
 - macOS: Fix :opt:`sync_to_monitor` not working on Mojave.
 
+- macOS: Use the system cursor blink interval by default
+  :opt:`cursor_blink_interval`.
+
+
 0.13.3 [2019-01-19]
 ------------------------------
 

kitty/cocoa_window.m

@@ -427,6 +427,21 @@ cocoa_get_lang(PyObject UNUSED *self) {
     return Py_BuildValue("s", [locale UTF8String]);
 }
 
+double
+cocoa_cursor_blink_interval(void) {
+    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
+    double on_period_ms = [defaults doubleForKey:@"NSTextInsertionPointBlinkPeriodOn"];
+    double off_period_ms = [defaults doubleForKey:@"NSTextInsertionPointBlinkPeriodOff"];
+    double period_ms = [defaults doubleForKey:@"NSTextInsertionPointBlinkPeriod"];
+    double max_value = 60 * 1000.0, ans = -1.0;
+    if (on_period_ms || off_period_ms) {
+        ans = on_period_ms + off_period_ms;
+    } else if (period_ms) {
+        ans = period_ms;
+    }
+    return ans > max_value ? 0.0 : ans;
+}
+
 void
 cocoa_set_hide_from_tasks(void) {
     [NSApp setActivationPolicy:NSApplicationActivationPolicyAccessory];

kitty/config_data.py

@@ -309,13 +309,15 @@ Choose the color of text under the cursor. If you want it rendered with the
 background color of the cell underneath instead, use the special keyword: background'''))
 o('cursor_shape', 'block', option_type=to_cursor_shape, long_text=_(
     'The cursor shape can be one of (block, beam, underline)'))
-o('cursor_blink_interval', 0.5, option_type=positive_float, long_text=_('''
+o('cursor_blink_interval', -1, option_type=float, long_text=_('''
 The interval (in seconds) at which to blink the cursor. Set to zero to disable
-blinking. Note that numbers smaller than :opt:`repaint_delay` will be limited
+blinking. Negative values mean use system default. Note that numbers smaller
-to :opt:`repaint_delay`. Stop blinking cursor after the specified number of
+than :opt:`repaint_delay` will be limited to :opt:`repaint_delay`.
-seconds of keyboard inactivity. Set to zero to never stop blinking.
+'''))
+o('cursor_stop_blinking_after', 15.0, option_type=positive_float, long_text=_('''
+Stop blinking cursor after the specified number of seconds of keyboard
+inactivity.  Set to zero to never stop blinking.
 '''))
-o('cursor_stop_blinking_after', 15.0, option_type=positive_float)
 
 # }}}
 

kitty/glfw.c

@@ -16,6 +16,7 @@ extern void cocoa_set_hide_from_tasks(void);
 extern void cocoa_set_titlebar_color(void *w, color_type color);
 extern bool cocoa_alt_option_key_pressed(unsigned long);
 extern size_t cocoa_get_workspace_ids(void *w, size_t *workspace_ids, size_t array_sz);
+extern double cocoa_cursor_blink_interval(void);
 
 
 #if GLFW_KEY_LAST >= MAX_KEY_COUNT
@@ -541,6 +542,13 @@ create_os_window(PyObject UNUSED *self, PyObject *args) {
     CC(standard, IBEAM); CC(click, HAND); CC(arrow, ARROW);
 #undef CC
         if (OPT(click_interval) < 0) OPT(click_interval) = glfwGetDoubleClickInterval(glfw_window);
+        if (OPT(cursor_blink_interval) < 0) {
+            OPT(cursor_blink_interval) = 0.5;
+#ifdef __APPLE__
+            double cbi = cocoa_cursor_blink_interval();
+            if (cbi >= 0) OPT(cursor_blink_interval) = cbi / 2.0;
+#endif
+        }
         is_first_window = false;
     }
     OSWindow *w = add_os_window();