patch 8.2.3954: Vim9: no error for shadowing if script var is declared later
Problem: Vim9: no error for shadowing if script var is declared later.
Solution: Check argument names when compiling a function.
diff --git a/src/vim9compile.c b/src/vim9compile.c
index 272368e..0418378 100644
--- a/src/vim9compile.c
+++ b/src/vim9compile.c
@@ -2393,6 +2393,34 @@
return NOTDONE;
}
+/*
+ * Check if arguments of "ufunc" shadow variables in "cctx".
+ * Return OK or FAIL.
+ */
+ static int
+check_args_shadowing(ufunc_T *ufunc, cctx_T *cctx)
+{
+ int i;
+ char_u *arg;
+ int r = OK;
+
+ // Make sure arguments are not found when compiling a second time.
+ ufunc->uf_args_visible = 0;
+
+ // Check for arguments shadowing variables from the context.
+ for (i = 0; i < ufunc->uf_args.ga_len; ++i)
+ {
+ arg = ((char_u **)(ufunc->uf_args.ga_data))[i];
+ if (check_defined(arg, STRLEN(arg), cctx, TRUE) == FAIL)
+ {
+ r = FAIL;
+ break;
+ }
+ }
+ ufunc->uf_args_visible = ufunc->uf_args.ga_len;
+ return r;
+}
+
/*
* Add a function to the list of :def functions.
@@ -2525,6 +2553,9 @@
estack_push_ufunc(ufunc, 1);
estack_compiling = TRUE;
+ if (check_args_shadowing(ufunc, &cctx) == FAIL)
+ goto erret;
+
if (ufunc->uf_def_args.ga_len > 0)
{
int count = ufunc->uf_def_args.ga_len;