Commit: patch 9.1.1791: type(void) throws an internal error

[Christian Brabandt]

patch 9.1.1791: type(void) throws an internal error

Commit: https://github.com/vim/vim/commit/f8eda33368500428840082aa3ad7a6868ae9d251
Author: Yegappan Lakshmanan <yega...@yahoo.com>
Date: Thu Sep 25 19:21:16 2025 +0000

patch 9.1.1791: type(void) throws an internal error

Problem: type(void) throws an internal error (atitcreate)
Solution: Return proper error message (Yegappan Lakshmanan)

fixes: #17310
closes: #18392

Signed-off-by: Yegappan Lakshmanan <yega...@yahoo.com>
Signed-off-by: Christian Brabandt <c...@256bit.org>

diff --git a/src/evalfunc.c b/src/evalfunc.c
index a8d190638..e4e0c29b2 100644
--- a/src/evalfunc.c
+++ b/src/evalfunc.c
@@ -12623,9 +12623,11 @@ f_type(typval_T *argvars, typval_T *rettv)
}
break;
}
+ case VAR_VOID:
+ emsg(_(e_cannot_use_void_value));
+ break;
case VAR_UNKNOWN:
case VAR_ANY:
- case VAR_VOID:
internal_error_no_abort("f_type(UNKNOWN)");
n = -1;
break;
diff --git a/src/evalvars.c b/src/evalvars.c
index e1eb89437..d9376530c 100644
--- a/src/evalvars.c
+++ b/src/evalvars.c
@@ -3359,7 +3359,7 @@ eval_variable(
}
}
}
- copy_tv(tv, rettv);
+ ret = copy_tv(tv, rettv);
}
}

diff --git a/src/proto/typval.pro b/src/proto/typval.pro
index 2080a262c..fcd9cd1c4 100644
--- a/src/proto/typval.pro
+++ b/src/proto/typval.pro
@@ -66,7 +66,7 @@ char_u *tv_get_string_buf_chk(typval_T *varp, char_u *buf);
char_u *tv_get_string_buf_chk_strict(typval_T *varp, char_u *buf, int strict);
char_u *tv_stringify(typval_T *varp, char_u *buf);
int tv_check_lock(typval_T *tv, char_u *name, int use_gettext);
-void copy_tv(typval_T *from, typval_T *to);
+int copy_tv(typval_T *from, typval_T *to);
int typval_compare2(typval_T *tv1, typval_T *tv2, exprtype_T type, int ic, int *res);
int typval_compare(typval_T *tv1, typval_T *tv2, exprtype_T type, int ic);
int typval_compare_list(typval_T *tv1, typval_T *tv2, exprtype_T type, int ic, int *res);
diff --git a/src/testdir/test_vim9_script.vim b/src/testdir/test_vim9_script.vim
index 823a6cf25..3c2c0cc07 100644
--- a/src/testdir/test_vim9_script.vim
+++ b/src/testdir/test_vim9_script.vim
@@ -5580,6 +5580,17 @@ def Test_multikey_dict_in_block()
unlet g:TestDict
enddef

+" Test for using the type() function with void
+def Test_type_func_with_void()
+ var lines =<< trim END
+ vim9script
+ def GetVoidValue(): void
+ enddef
+ echo type(GetVoidValue())
+ END
+ v9.CheckSourceFailure(lines, 'E1031: Cannot use void value', 4)
+enddef
+
" Keep this last, it messes up highlighting.
def Test_substitute_cmd()
new
diff --git a/src/testdir/test_vimscript.vim b/src/testdir/test_vimscript.vim
index bf5a875f1..0be53dc5a 100644
--- a/src/testdir/test_vimscript.vim
+++ b/src/testdir/test_vimscript.vim
@@ -6522,7 +6522,7 @@ func Test_type()
endif
call assert_equal(v:t_blob, type(test_null_blob()))

- call assert_fails("call type(test_void())", ['E340:', 'E685:'])
+ call assert_fails("call type(test_void())", ['E1031: Cannot use void value', 'E1031: Cannot use void value'])
call assert_fails("call type(test_unknown())", ['E340:', 'E685:'])

call assert_equal(0, 0 + v:false)
@@ -6599,6 +6599,10 @@ func Test_type()
call assert_true(empty(v:null))
call assert_true(empty(v:none))

+ def s:GetVoidValue(): void
+ enddef
+ call assert_fails('let x = type(s:GetVoidValue())', 'E1031: Cannot use void value')
+
func ChangeYourMind()
try
return v:true
diff --git a/src/typval.c b/src/typval.c
index b4ee7ec63..7dc3e8673 100644
--- a/src/typval.c
+++ b/src/typval.c
@@ -1357,9 +1357,11 @@ tv_check_lock(typval_T *tv, char_u *name, int use_gettext)
* It is OK for "from" and "to" to point to the same item. This is used to
* make a copy later.
*/
- void
+ int
copy_tv(typval_T *from, typval_T *to)
{
+ int ret = OK;
+
to->v_type = from->v_type;
to->v_lock = 0;
switch (from->v_type)
@@ -1465,12 +1467,16 @@ copy_tv(typval_T *from, typval_T *to)
break;
case VAR_VOID:
emsg(_(e_cannot_use_void_value));
+ ret = FAIL;
break;
case VAR_UNKNOWN:
case VAR_ANY:
internal_error_no_abort("copy_tv(UNKNOWN)");
+ ret = FAIL;
break;
}
+
+ return ret;
}

/*
diff --git a/src/version.c b/src/version.c
index daf0d5f97..f48b3d79e 100644
--- a/src/version.c
+++ b/src/version.c
@@ -729,6 +729,8 @@ static char *(features[]) =

static int included_patches[] =
{ /* Add new patch number below this line */
+/**/
+ 1791,
/**/
1790,
/**/