checker: fix empty array append multi dims (fix #23092) (#23096)

vlib/v/checker/containers.v

@@ -169,7 +169,15 @@ fn (mut c Checker) array_init(mut node ast.ArrayInit) ast.Type {
 			}
 		}
 		for i, mut expr in node.exprs {
-			mut typ := c.check_expr_option_or_result_call(expr, c.expr(mut expr))
+			mut typ := ast.void_type
+			if expr is ast.ArrayInit {
+				old_expected_type := c.expected_type
+				c.expected_type = c.table.value_type(c.expected_type)
+				typ = c.check_expr_option_or_result_call(expr, c.expr(mut expr))
+				c.expected_type = old_expected_type
+			} else {
+				typ = c.check_expr_option_or_result_call(expr, c.expr(mut expr))
+			}
 			if expr is ast.CallExpr {
 				ret_sym := c.table.sym(typ)
 				if ret_sym.kind == .array_fixed {

vlib/v/tests/empty_array_push_test.v

@@ -0,0 +1,21 @@
+fn test_3dims() {
+	mut array := [][][]int{}
+	array << [[1]]
+	dump(array)
+	array << [[[1]]]
+	dump(array)
+	array << [[[]]]
+	println(array)
+	assert array == [[[int(1)]], [[1]], [[]int{}]]
+}
+
+fn test_2dims() {
+	mut array := [][]int{}
+	array << [1]
+	dump(array)
+	array << [[1]]
+	dump(array)
+	array << [[]]
+	println(array)
+	assert array == [[int(1)], [1], []int{}]
+}