vim-patch:8.2.3838: cannot use script-local function for setting *func options

Problem:    Cannot use script-local function for setting *func options.
Solution:   Use the script context. (Yegappan Lakshmanan, closes vim/vim#9362)

https://github.com/vim/vim/commit/db1a410b610b2c1941311acc57dcc4afec20720e

Co-authored-by: Yegappan Lakshmanan <yegappan@yahoo.com>

1 files changed, 20 insertions, 5 deletions

diff --git a/src/nvim/option.c b/src/nvim/option.c
index 72090fdbcc..6d461d9b9d 100644
--- a/src/nvim/option.c
+++ b/src/nvim/option.c
@@ -5157,10 +5157,6 @@ int option_set_callback_func(char *optval, Callback *optcb)
     return OK;
   }
 
-  if (strncmp(optval, "s:", 2) == 0 && !SCRIPT_ID_VALID(current_sctx.sc_sid)) {
-    return FAIL;
-  }
-
   typval_T *tv;
   if (*optval == '{'
       || (strncmp(optval, "function(", 9) == 0)
@@ -5174,7 +5170,26 @@ int option_set_callback_func(char *optval, Callback *optcb)
     // treat everything else as a function name string
     tv = xcalloc(1, sizeof(*tv));
     tv->v_type = VAR_STRING;
-    tv->vval.v_string = xstrdup(optval);
+
+    // Function name starting with "s:" are supported only in a vimscript
+    // context.
+    if (strncmp(optval, "s:", 2) == 0) {
+      char sid_buf[25];
+
+      if (!SCRIPT_ID_VALID(current_sctx.sc_sid)) {
+        emsg(_(e_usingsid));
+        return FAIL;
+      }
+      // Expand s: prefix into <SNR>nr_<name>
+      snprintf(sid_buf, sizeof(sid_buf), "<SNR>%" PRId64 "_",
+               (int64_t)current_sctx.sc_sid);
+      char *funcname = xmalloc(strlen(sid_buf) + strlen(optval + 2) + 1);
+      STRCPY(funcname, sid_buf);
+      STRCAT(funcname, optval + 2);
+      tv->vval.v_string = funcname;
+    } else {
+      tv->vval.v_string = xstrdup(optval);
+    }
   }
 
   Callback cb;