patch 9.0.1830: Vim9: crash when accessing a null object
Problem: Vim9: crash when accessing a null object
Solution: Check accessing a NULL object in def function
An object is NULL when the variable is declared, but the constructor
isn't called. Accessing/setting a member on the object crashed Vim.
Note: this happens inside def functions, at script level things work
differently. Accessing a NULL object member results in E1360
(correctly), while setting a value on it results in E1012 (type
mismatch) so there's still something to fix.
closes: #12973
Signed-off-by: Christian Brabandt <cb@256bit.org>
Co-authored-by: Gianmaria Bajo <mg1979.git@gmail.com>
diff --git a/src/vim9execute.c b/src/vim9execute.c
index 2eb6ba4..b26934d 100644
--- a/src/vim9execute.c
+++ b/src/vim9execute.c
@@ -2147,7 +2147,14 @@
// -1 dict, list, blob or object
tv = STACK_TV_BOT(-3);
SOURCING_LNUM = iptr->isn_lnum;
- if (dest_type == VAR_ANY)
+
+ // Make sure an object has been initialized
+ if (dest_type == VAR_OBJECT && tv_dest->vval.v_object == NULL)
+ {
+ emsg(_(e_using_null_object));
+ status = FAIL;
+ }
+ else if (dest_type == VAR_ANY)
{
dest_type = tv_dest->v_type;
if (dest_type == VAR_DICT)