patch 9.1.1527: Vim9: Crash with string compound assignment

h-east · chrisbra · commit 2ffd35fe8fad · 2025-07-08T21:49:56.000+02:00
Problem: Vim9: Crash when using string compound assignment with wrong data type (lacygoill) Solution: verify expected member type (Hirohito Higashi) fixes: #17675 closes: #17693 Signed-off-by: Hirohito Higashi <h.east.727@gmail.com> Signed-off-by: Yegappan Lakshmanan <yegappan@yahoo.com> Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/testdir/test_vim9_assign.vim b/src/testdir/test_vim9_assign.vim
@@ -187,6 +187,7 @@ def Test_assignment()
 
   v9.CheckDefFailure(['&notex += 3'], 'E113:')
   v9.CheckDefFailure(['&ts ..= "xxx"'], 'E1019:')
+  v9.CheckDefFailure(['var d = {k: [0]}', 'd.k ..= "x"'], 'E1012: Type mismatch; expected list<number> but got string')
   v9.CheckDefFailure(['&ts = [7]'], 'E1012:')
   v9.CheckDefExecFailure(['&ts = g:alist'], 'E1012: Type mismatch; expected number but got list<number>')
   v9.CheckDefFailure(['&ts = "xx"'], 'E1012:')
diff --git a/src/version.c b/src/version.c
@@ -719,6 +719,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1527,
 /**/
     1526,
 /**/
diff --git a/src/vim9compile.c b/src/vim9compile.c
@@ -3444,7 +3444,13 @@ compile_assign_compound_op(cctx_T *cctx, cac_T *cac)
 
     if (*cac->cac_op == '.')
     {
-	if (may_generate_2STRING(-1, TOSTRING_NONE, cctx) == FAIL)
+	expected = lhs->lhs_member_type;
+	stacktype = get_type_on_stack(cctx, 0);
+	if (expected != &t_string
+		&& need_type(stacktype, expected, FALSE, -1, 0, cctx,
+					FALSE, FALSE) == FAIL)
+	    return FAIL;
+	else if (may_generate_2STRING(-1, TOSTRING_NONE, cctx) == FAIL)
 	    return FAIL;
     }
     else

Original file line number	Diff line number	Diff line change
`@@ -3444,7 +3444,13 @@ compile_assign_compound_op(cctx_T cctx, cac_T cac)`
`3444`	`3444`
`3445`	`3445`	`if (*cac->cac_op == '.')`
`3446`	`3446`	`{`
`3447`		`- if (may_generate_2STRING(-1, TOSTRING_NONE, cctx) == FAIL)`
	`3447`	`+ expected = lhs->lhs_member_type;`
	`3448`	`+ stacktype = get_type_on_stack(cctx, 0);`
	`3449`	`+ if (expected != &t_string`
	`3450`	`+ && need_type(stacktype, expected, FALSE, -1, 0, cctx,`
	`3451`	`+ FALSE, FALSE) == FAIL)`
	`3452`	`+ return FAIL;`
	`3453`	`+ else if (may_generate_2STRING(-1, TOSTRING_NONE, cctx) == FAIL)`
`3448`	`3454`	`return FAIL;`
`3449`	`3455`	`}`
`3450`	`3456`	`else`