fix(tui): set id parameter in OSC 8 sequences (#29840)

The id parameter is used to communicate to the terminal that two URLs
are the same. Without an id, the terminal must rely on heuristics to
determine which cells belong together to make a single hyperlink.

See the relevant section in the spec [1] for more details.

[1]: https://gist.github.com/egmontkob/eb114294efbcd5adb1944c9f3cb5feda#hover-underlining-and-the-id-parameter

2 files changed, 10 insertions, 5 deletions

diff --git a/src/nvim/tui/tui.c b/src/nvim/tui/tui.c
index c7ec013b28..0adf0712c0 100644
--- a/src/nvim/tui/tui.c
+++ b/src/nvim/tui/tui.c
@@ -793,7 +793,12 @@ static void update_attrs(TUIData *tui, int attr_id)
     if (attrs.url >= 0) {
       const char *url = urls.keys[attrs.url];
       kv_size(tui->urlbuf) = 0;
-      kv_printf(tui->urlbuf, "\x1b]8;;%s\x1b\\", url);
+
+      // Add some fixed offset to the URL ID to deconflict with other
+      // applications which may set their own IDs
+      const uint64_t id = 0xE1EA0000U + (uint32_t)attrs.url;
+
+      kv_printf(tui->urlbuf, "\x1b]8;id=%" PRIu64 ";%s\x1b\\", id, url);
       out(tui, tui->urlbuf.items, kv_size(tui->urlbuf));
     } else {
       out(tui, S_LEN("\x1b]8;;\x1b\\"));
diff --git a/test/functional/terminal/tui_spec.lua b/test/functional/terminal/tui_spec.lua
index 3e0b907ea2..50199bd83d 100644
--- a/test/functional/terminal/tui_spec.lua
+++ b/test/functional/terminal/tui_spec.lua
@@ -1968,9 +1968,9 @@ describe('TUI', function()
           if not req then
             return
           end
-          local url = req:match('\027]8;;(.*)$')
-          if url ~= nil then
-            table.insert(_G.urls, url)
+          local id, url = req:match('\027]8;id=(%d+);(.*)$')
+          if id ~= nil and url ~= nil then
+            table.insert(_G.urls, { id = tonumber(id), url = url })
           end
         end,
       })
@@ -1984,7 +1984,7 @@ describe('TUI', function()
       })
     ]])
     retry(nil, 1000, function()
-      eq({ 'https://example.com', '' }, exec_lua([[return _G.urls]]))
+      eq({ { id = 0xE1EA0000, url = 'https://example.com' } }, exec_lua([[return _G.urls]]))
     end)
   end)
 end)