fix(terminal): fix OSC 8 parsing (#34424)

vterm does not send us the terminator in the string fragment. Our OSC 8
parser assumed that it was and therefore treated short strings as
invalid (as it assumed it was missing a terminator).

(cherry picked from commit b5aef05b8f)

src/nvim/terminal.c

@@ -283,31 +283,22 @@ static int parse_osc8(VTermStringFragment frag, int *attr)
     }
   }
 
-  // Move past the semicolon
-  i++;
-
-  if (i >= frag.len) {
+  if (frag.str[i] != ';') {
     // Invalid OSC sequence
     return 0;
   }
 
-  // Find the terminator
-  const size_t start = i;
-  for (; i < frag.len; i++) {
-    if (frag.str[i] == '\a' || frag.str[i] == '\x1b') {
-      break;
-    }
-  }
+  // Move past the semicolon
+  i++;
 
-  const size_t len = i - start;
-  if (len == 0) {
+  if (i >= frag.len) {
     // Empty OSC 8, no URL
     *attr = 0;
     return 1;
   }
 
-  char *url = xmemdupz(&frag.str[start], len + 1);
-  url[len] = 0;
+  char *url = xmemdupz(&frag.str[i], frag.len - i + 1);
+  url[frag.len - i] = 0;
   *attr = hl_add_url(0, url);
   xfree(url);
 

test/functional/terminal/highlight_spec.lua

@@ -398,12 +398,13 @@ describe(':terminal', function()
       [100] = { url = 'https://example.com' },
     }
     local chan = api.nvim_open_term(0, {})
-    api.nvim_chan_send(chan, '\027]8;;https://example.com\027\\Example\027]8;;\027\\')
-    screen:expect({
-      grid = [[
-        {100:^Example}                                           |
-                                                          |*6
-      ]],
-    })
+    api.nvim_chan_send(
+      chan,
+      'This is an \027]8;;https://example.com\027\\example\027]8;;\027\\ of a link'
+    )
+    screen:expect([[
+      ^This is an {100:example} of a link                      |
+                                                        |*6
+    ]])
   end)
 end)