Show the target of terminal hyperlinks when hovering over them with the mouse

Fixes #5830

docs/changelog.rst

@@ -47,6 +47,8 @@ Detailed list of changes
 - Speed up the ``kitty @`` executable by ~10x reducing the time for typical
   remote control commands from ~50ms to ~5ms
 
+- Show the target of terminal hyperlinks when hovering over them with the mouse controlled by :opt:`show_hyperlink_targets` (:pull:`5830`)
+
 - Keyboard protocol: Remove ``CSI R`` from the allowed encodings of the :kbd:`F3` key as it conflicts with the *Cursor Position Report* escape code (:disc:`5813`)
 
 - Allow using the cwd of the original process for :option:`launch --cwd` (:iss:`5672`)

kitty/boss.py

@@ -8,7 +8,7 @@ import os
 import re
 import sys
 from contextlib import suppress
-from functools import partial
+from functools import lru_cache, partial
 from gettext import gettext as _
 from time import monotonic, sleep
 from typing import (
@@ -33,21 +33,19 @@ from .constants import (
 )
 from .fast_data_types import (
     CLOSE_BEING_CONFIRMED, GLFW_MOD_ALT, GLFW_MOD_CONTROL, GLFW_MOD_SHIFT,
-    GLFW_MOD_SUPER, GLFW_MOUSE_BUTTON_LEFT, GLFW_PRESS,
+    GLFW_MOD_SUPER, GLFW_MOUSE_BUTTON_LEFT, GLFW_PRESS, IMPERATIVE_CLOSE_REQUESTED,
-    IMPERATIVE_CLOSE_REQUESTED, NO_CLOSE_REQUESTED, ChildMonitor, Color,
+    NO_CLOSE_REQUESTED, ChildMonitor, Color, EllipticCurveKey, KeyEvent, SingleKey,
-    EllipticCurveKey, KeyEvent, SingleKey, add_timer, apply_options_update,
+    add_timer, apply_options_update, background_opacity_of, change_background_opacity,
-    background_opacity_of, change_background_opacity, change_os_window_state,
+    change_os_window_state, cocoa_hide_app, cocoa_hide_other_apps,
-    cocoa_hide_app, cocoa_hide_other_apps, cocoa_minimize_os_window,
+    cocoa_minimize_os_window, cocoa_set_menubar_title, create_os_window,
-    cocoa_set_menubar_title, create_os_window,
+    current_application_quit_request, current_focused_os_window_id, current_os_window,
-    current_application_quit_request, current_focused_os_window_id,
+    destroy_global_data, focus_os_window, get_boss, get_options, get_os_window_size,
-    current_os_window, destroy_global_data, focus_os_window, get_boss,
+    global_font_size, last_focused_os_window_id, mark_os_window_for_close,
-    get_options, get_os_window_size, global_font_size,
+    os_window_font_size, patch_global_colors, redirect_mouse_handling, ring_bell,
-    last_focused_os_window_id, mark_os_window_for_close, os_window_font_size,
-    patch_global_colors, redirect_mouse_handling, ring_bell,
     run_with_activation_token, safe_pipe, send_data_to_peer,
-    set_application_quit_request, set_background_image, set_boss,
+    set_application_quit_request, set_background_image, set_boss, set_in_sequence_mode,
-    set_in_sequence_mode, set_options, set_os_window_size, set_os_window_title,
+    set_options, set_os_window_size, set_os_window_title, thread_write,
-    thread_write, toggle_fullscreen, toggle_maximized, toggle_secure_input,
+    toggle_fullscreen, toggle_maximized, toggle_secure_input,
 )
 from .key_encoding import get_name_to_functional_number_map
 from .keys import get_shortcut, shortcut_matches
@@ -2604,3 +2602,8 @@ class Boss:
     def discard_event(self) -> None:
         pass
     mouse_discard_event = discard_event
+
+    @lru_cache(maxsize=64)
+    def sanitize_url_for_dispay_to_user(self, url: str) -> str:
+        # TODO: Use punycode, remove percent encoding, etc.
+        return url

kitty/mouse.c

@@ -340,8 +340,16 @@ handle_mouse_movement_in_kitty(Window *w, int button, bool mouse_cell_changed) {
 
 static void
 detect_url(Screen *screen, unsigned int x, unsigned int y) {
-    if (screen_detect_url(screen, x, y)) mouse_cursor_shape = HAND;
+    int hid = screen_detect_url(screen, x, y);
-    else set_mouse_cursor_for_screen(screen);
+    screen->current_hyperlink_under_mouse.id = 0;
+    if (hid != 0) {
+        mouse_cursor_shape = HAND;
+        if (hid > 0) {
+            screen->current_hyperlink_under_mouse.id = (hyperlink_id_type)hid;
+            screen->current_hyperlink_under_mouse.x = x;
+            screen->current_hyperlink_under_mouse.y = y;
+        }
+    } else set_mouse_cursor_for_screen(screen);
 }
 
 static bool

kitty/options/definition.py

@@ -432,6 +432,10 @@ mouse cursor. By default, all characters that are legal in URLs are allowed.
 '''
     )
 
+opt('show_hyperlink_targets', 'yes', option_type='to_bool', ctype='bool', long_text='''
+When the mouse hovers over a terminal hyperlink, show the actual URL that will be
+activated when the hyperlink is clicked.''')
+
 opt('copy_on_select', 'no',
     option_type='copy_on_select',
     long_text='''

kitty/options/parse.py

@@ -1185,6 +1185,9 @@ class Parser:
     def shell_integration(self, val: str, ans: typing.Dict[str, typing.Any]) -> None:
         ans['shell_integration'] = shell_integration(val)
 
+    def show_hyperlink_targets(self, val: str, ans: typing.Dict[str, typing.Any]) -> None:
+        ans['show_hyperlink_targets'] = to_bool(val)
+
     def single_window_margin_width(self, val: str, ans: typing.Dict[str, typing.Any]) -> None:
         ans['single_window_margin_width'] = optional_edge_width(val)
 

kitty/options/to-c-generated.h

@@ -265,6 +265,19 @@ convert_from_opts_url_excluded_characters(PyObject *py_opts, Options *opts) {
     Py_DECREF(ret);
 }
 
+static void
+convert_from_python_show_hyperlink_targets(PyObject *val, Options *opts) {
+    opts->show_hyperlink_targets = PyObject_IsTrue(val);
+}
+
+static void
+convert_from_opts_show_hyperlink_targets(PyObject *py_opts, Options *opts) {
+    PyObject *ret = PyObject_GetAttrString(py_opts, "show_hyperlink_targets");
+    if (ret == NULL) return;
+    convert_from_python_show_hyperlink_targets(ret, opts);
+    Py_DECREF(ret);
+}
+
 static void
 convert_from_python_select_by_word_characters(PyObject *val, Options *opts) {
     select_by_word_characters(val, opts);
@@ -1061,6 +1074,8 @@ convert_opts_from_python_opts(PyObject *py_opts, Options *opts) {
     if (PyErr_Occurred()) return false;
     convert_from_opts_url_excluded_characters(py_opts, opts);
     if (PyErr_Occurred()) return false;
+    convert_from_opts_show_hyperlink_targets(py_opts, opts);
+    if (PyErr_Occurred()) return false;
     convert_from_opts_select_by_word_characters(py_opts, opts);
     if (PyErr_Occurred()) return false;
     convert_from_opts_select_by_word_characters_forward(py_opts, opts);

kitty/options/types.py

@@ -418,6 +418,7 @@ option_names = (  # {{{
  'selection_foreground',
  'shell',
  'shell_integration',
+ 'show_hyperlink_targets',
  'single_window_margin_width',
  'startup_session',
  'strip_trailing_spaces',
@@ -568,6 +569,7 @@ class Options:
     selection_foreground: typing.Optional[kitty.fast_data_types.Color] = Color(0, 0, 0)
     shell: str = '.'
     shell_integration: typing.FrozenSet[str] = frozenset({'enabled'})
+    show_hyperlink_targets: bool = True
     single_window_margin_width: FloatEdges = FloatEdges(left=-1.0, top=-1.0, right=-1.0, bottom=-1.0)
     startup_session: typing.Optional[str] = None
     strip_trailing_spaces: choices_for_strip_trailing_spaces = 'never'

kitty/screen.c

@@ -2722,15 +2722,16 @@ get_url_sentinel(Line *line, index_type url_start) {
     return sentinel;
 }
 
-bool
+int
 screen_detect_url(Screen *screen, unsigned int x, unsigned int y) {
     bool has_url = false;
     index_type url_start, url_end = 0;
     Line *line = screen_visual_line(screen, y);
-    if (!line || x >= screen->columns) return false;
+    if (!line || x >= screen->columns) return 0;
-    if (line->cpu_cells[x].hyperlink_id) {
+    hyperlink_id_type hid;
+    if ((hid = line->cpu_cells[x].hyperlink_id)) {
         screen_mark_hyperlink(screen, x, y);
-        return true;
+        return hid;
     }
     char_type sentinel = 0;
     if (line) {
@@ -2754,7 +2755,7 @@ screen_detect_url(Screen *screen, unsigned int x, unsigned int y) {
     } else {
         screen_mark_url(screen, 0, 0, 0, 0);
     }
-    return has_url;
+    return has_url ? -1 : 0;
 }
 
 

kitty/screen.h

@@ -150,6 +150,10 @@ typedef struct {
         bool is_set;
     } last_visited_prompt;
     PyObject *last_reported_cwd;
+    struct {
+        hyperlink_id_type id;
+        index_type x, y;
+    } current_hyperlink_under_mouse;
 } Screen;
 
 
@@ -261,7 +265,7 @@ void screen_push_key_encoding_flags(Screen *self, uint32_t val);
 void screen_pop_key_encoding_flags(Screen *self, uint32_t num);
 uint8_t screen_current_key_encoding_flags(Screen *self);
 void screen_report_key_encoding_flags(Screen *self);
-bool screen_detect_url(Screen *screen, unsigned int x, unsigned int y);
+int screen_detect_url(Screen *screen, unsigned int x, unsigned int y);
 int screen_cursor_at_a_shell_prompt(const Screen *);
 bool screen_fake_move_cursor_to_position(Screen *, index_type x, index_type y);
 bool screen_send_signal_for_key(Screen *, char key);

kitty/shaders.c

@@ -571,32 +571,38 @@ set_cell_uniforms(float current_inactive_text_alpha, bool force) {
 }
 
 static GLfloat
-render_window_title(OSWindow *os_window, Screen *screen UNUSED, GLfloat xstart, GLfloat ystart, GLfloat width, Window *window, GLfloat left, GLfloat right) {
+render_a_bar(OSWindow *os_window, Screen *screen, const CellRenderData *crd, WindowBarData *bar, PyObject *title, bool along_bottom) {
+    GLfloat left = os_window->viewport_width * (crd->gl.xstart + 1.f) / 2.f;
+    GLfloat right = left + os_window->viewport_width * crd->gl.width / 2.f;
     unsigned bar_height = os_window->fonts_data->cell_height + 2;
     if (!bar_height || right <= left) return 0;
     unsigned bar_width = (unsigned)ceilf(right - left);
-    if (!window->title_bar_data.buf || window->title_bar_data.width != bar_width || window->title_bar_data.height != bar_height) {
+    if (!bar->buf || bar->width != bar_width || bar->height != bar_height) {
-        free(window->title_bar_data.buf);
+        free(bar->buf);
-        Py_CLEAR(window->title_bar_data.last_drawn_title_object_id);
+        bar->buf = malloc((size_t)4 * bar_width * bar_height);
-        window->title_bar_data.buf = malloc((size_t)4 * bar_width * bar_height);
+        if (!bar->buf) return 0;
-        if (!window->title_bar_data.buf) return 0;
+        bar->height = bar_height;
-        window->title_bar_data.height = bar_height;
+        bar->width = bar_width;
-        window->title_bar_data.width = bar_width;
+        bar->needs_render = true;
     }
-    static char title[2048] = {0};
+
-    if (window->title_bar_data.last_drawn_title_object_id != window->title) {
+    if (bar->last_drawn_title_object_id != title || bar->needs_render) {
-        snprintf(title, arraysz(title), " %s", PyUnicode_AsUTF8(window->title));
+        static char titlebuf[2048] = {0};
+        if (!title) return 0;
+        snprintf(titlebuf, arraysz(titlebuf), " %s", PyUnicode_AsUTF8(title));
 #define RGBCOL(which, fallback) ( 0xff000000 | colorprofile_to_color_with_fallback(screen->color_profile, screen->color_profile->overridden.which, screen->color_profile->configured.which, screen->color_profile->overridden.fallback, screen->color_profile->configured.fallback))
-        if (!draw_window_title(os_window, title, RGBCOL(highlight_fg, default_fg), RGBCOL(highlight_bg, default_bg), window->title_bar_data.buf, bar_width, bar_height)) return 0;
+        if (!draw_window_title(os_window, titlebuf, RGBCOL(highlight_fg, default_fg), RGBCOL(highlight_bg, default_bg), bar->buf, bar_width, bar_height)) return 0;
 #undef RGBCOL
-        window->title_bar_data.last_drawn_title_object_id = window->title;
+        bar->last_drawn_title_object_id = title;
-        Py_INCREF(window->title_bar_data.last_drawn_title_object_id);
+        Py_INCREF(bar->last_drawn_title_object_id);
     }
     static ImageRenderData data = {.group_count=1};
-    xstart = clamp_position_to_nearest_pixel(xstart, os_window->viewport_width);
+    GLfloat xstart, ystart;
-    ystart = clamp_position_to_nearest_pixel(ystart, os_window->viewport_height);
+    xstart = clamp_position_to_nearest_pixel(crd->gl.xstart, os_window->viewport_width);
     GLfloat height_gl = gl_size(bar_height, os_window->viewport_height);
-    gpu_data_for_image(&data, xstart, ystart, xstart + width, ystart - height_gl);
+    if (along_bottom) ystart = crd->gl.ystart - crd->gl.height + height_gl;
+    else ystart = clamp_position_to_nearest_pixel(crd->gl.ystart, os_window->viewport_height);
+    gpu_data_for_image(&data, xstart, ystart, xstart + crd->gl.width, ystart - height_gl);
     if (!data.texture_id) { glGenTextures(1, &data.texture_id); }
     glBindTexture(GL_TEXTURE_2D, data.texture_id);
     glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
@@ -604,7 +610,7 @@ render_window_title(OSWindow *os_window, Screen *screen UNUSED, GLfloat xstart,
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
-    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, bar_width, bar_height, 0, GL_RGBA, GL_UNSIGNED_BYTE, window->title_bar_data.buf);
+    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, bar_width, bar_height, 0, GL_RGBA, GL_UNSIGNED_BYTE, bar->buf);
     set_cell_uniforms(1.f, false);
     bind_program(GRAPHICS_PROGRAM);
     send_graphics_data_to_gpu(1, os_window->gvao_idx, &data);
@@ -615,6 +621,25 @@ render_window_title(OSWindow *os_window, Screen *screen UNUSED, GLfloat xstart,
     return height_gl;
 }
 
+static void
+draw_hyperlink_target(OSWindow *os_window, Screen *screen, const CellRenderData *crd, Window *window) {
+    WindowBarData *bd = &window->url_target_bar_data;
+    if (bd->hyperlink_id_for_title_object != screen->current_hyperlink_under_mouse.id) {
+        bd->hyperlink_id_for_title_object = screen->current_hyperlink_under_mouse.id;
+        Py_CLEAR(bd->last_drawn_title_object_id);
+        const char *url = get_hyperlink_for_id(screen->hyperlink_pool, bd->hyperlink_id_for_title_object, true);
+        if (url == NULL) url = "";
+        PyObject *h = PyObject_CallMethod(global_state.boss, "sanitize_url_for_dispay_to_user", "s", url);
+        if (h == NULL) { PyErr_Print(); return; }
+        bd->last_drawn_title_object_id = h;
+        Py_INCREF(bd->last_drawn_title_object_id);
+        bd->needs_render = true;
+    }
+    if (bd->last_drawn_title_object_id == NULL) return;
+    const bool along_bottom = screen->lines < 3 || screen->current_hyperlink_under_mouse.y < screen->lines - 2;
+    render_a_bar(os_window, screen, crd, &window->title_bar_data, bd->last_drawn_title_object_id, along_bottom);
+}
+
 static void
 draw_window_logo(ssize_t vao_idx, OSWindow *os_window, const WindowLogoRenderData *wl, const CellRenderData *crd) {
     if (os_window->live_resize.in_progress) return;
@@ -642,7 +667,7 @@ draw_window_number(OSWindow *os_window, Screen *screen, const CellRenderData *cr
     GLfloat title_bar_height = 0;
     size_t requested_height = (size_t)(os_window->viewport_height * crd->gl.height / 2.f);
     if (window->title && PyUnicode_Check(window->title) && (requested_height > (os_window->fonts_data->cell_height + 1) * 2)) {
-        title_bar_height = render_window_title(os_window, screen, crd->gl.xstart, crd->gl.ystart, crd->gl.width, window, left, right);
+        title_bar_height = render_a_bar(os_window, screen, crd, &window->title_bar_data, window->title, false);
     }
     GLfloat ystart = crd->gl.ystart, height = crd->gl.height, xstart = crd->gl.xstart, width = crd->gl.width;
     if (title_bar_height > 0) {
@@ -933,6 +958,7 @@ draw_cells(ssize_t vao_idx, ssize_t gvao_idx, const ScreenRenderData *srd, float
     }
 
     if (window && screen->display_window_char) draw_window_number(os_window, screen, &crd, window);
+    if (OPT(show_hyperlink_targets) && window && screen->current_hyperlink_under_mouse.id) draw_hyperlink_target(os_window, screen, &crd, window);
 }
 // }}}
 

kitty/state.c

@@ -335,6 +335,8 @@ destroy_window(Window *w) {
     Py_CLEAR(w->render_data.screen); Py_CLEAR(w->title);
     Py_CLEAR(w->title_bar_data.last_drawn_title_object_id);
     free(w->title_bar_data.buf); w->title_bar_data.buf = NULL;
+    Py_CLEAR(w->url_target_bar_data.last_drawn_title_object_id);
+    free(w->url_target_bar_data.buf); w->url_target_bar_data.buf = NULL;
     release_gpu_resources_for_window(w);
     if (w->window_logo.id) {
         decref_window_logo(global_state.all_window_logos, w->window_logo.id);

kitty/state.h

@@ -87,6 +87,7 @@ typedef struct {
     struct {
         float val; AdjustmentUnit unit;
     } underline_position, underline_thickness, strikethrough_position, strikethrough_thickness, cell_width, cell_height, baseline;
+    bool show_hyperlink_targets;
 } Options;
 
 typedef struct WindowLogoRenderData {
@@ -126,6 +127,14 @@ typedef struct MousePosition {
     bool in_left_half_of_cell;
 } MousePosition;
 
+typedef struct WindowBarData {
+    unsigned width, height;
+    uint8_t *buf;
+    PyObject *last_drawn_title_object_id;
+    hyperlink_id_type hyperlink_id_for_title_object;
+    bool needs_render;
+} WindowBarData;
+
 typedef struct {
     id_type id;
     bool visible, cursor_visible_at_last_render;
@@ -142,11 +151,7 @@ typedef struct {
     ClickQueue click_queues[8];
     monotonic_t last_drag_scroll_at;
     uint32_t last_special_key_pressed;
-    struct {
+    WindowBarData title_bar_data, url_target_bar_data;
-        unsigned width, height;
-        uint8_t *buf;
-        PyObject *last_drawn_title_object_id;
-    } title_bar_data;
 } Window;
 
 typedef struct {