checker: fix missing check for or-block on selectorexpr (#17975)

vlib/v/checker/checker.v

@@ -1127,8 +1127,7 @@ fn (mut c Checker) check_or_last_stmt(stmt ast.Stmt, ret_type ast.Type, expr_ret
 				c.expected_or_type = ret_type.clear_flags(.option, .result)
 				last_stmt_typ := c.expr(stmt.expr)
 
-				if ret_type.has_flag(.option)
-					&& (last_stmt_typ.has_flag(.option) || last_stmt_typ == ast.none_type) {
+				if last_stmt_typ.has_flag(.option) || last_stmt_typ == ast.none_type {
 					if stmt.expr in [ast.Ident, ast.SelectorExpr, ast.CallExpr, ast.None] {
 						expected_type_name := c.table.type_to_str(ret_type.clear_flags(.option,
 							.result))
@@ -1440,6 +1439,7 @@ fn (mut c Checker) selector_expr(mut node ast.SelectorExpr) ast.Type {
 		if node.or_block.kind == .block {
 			c.expected_or_type = node.typ.clear_flags(.option, .result)
 			c.stmts_ending_with_expression(node.or_block.stmts)
+			c.check_or_expr(node.or_block, node.typ, c.expected_or_type, node)
 			c.expected_or_type = ast.void_type
 		}
 		return field.typ

vlib/v/checker/tests/option_selector_or_block_err.out

@@ -0,0 +1,7 @@
+vlib/v/checker/tests/option_selector_or_block_err.vv:9:10: error: `or` block must provide a value of type `[]string`, not `?[]string`
+    7 |   return post.authors or {
+    8 |     post.authors = []string{}
+    9 |     post.authors
+      |          ~~~~~~~
+   10 |   }
+   11 | }

vlib/v/checker/tests/option_selector_or_block_err.vv

@@ -0,0 +1,17 @@
+struct Post {
+mut:
+  authors ?[]string
+}
+
+fn populate(mut post Post) []string {
+  return post.authors or {
+    post.authors = []string{}
+    post.authors
+  }
+}
+
+fn main() {
+  mut test := Post {}
+  populate(mut test)
+  println(test)
+}

vlib/v/checker/tests/wrong_none_on_or_block_err.out

@@ -1,4 +1,4 @@
-vlib/v/checker/tests/wrong_none_on_or_block_err.vv:8:22: error: wrong return type `none` in the `or {}` block, expected `int`
+vlib/v/checker/tests/wrong_none_on_or_block_err.vv:8:22: error: `or` block must provide a value of type `int`, not `none`
     6 |         `ő`: 25
     7 |     }
     8 |     println(m[`4`] or { none })