From d040af4939c45730537412191a07658ab395b417 Mon Sep 17 00:00:00 2001
From: pancake <pancake@nowsecure.com>
Date: Mon, 2 Nov 2020 03:52:35 +0100
Subject: [PATCH] checker: improve error message for: `a := foo() or {
 println(err) }` (#6710)

---
 vlib/v/checker/checker.v | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/vlib/v/checker/checker.v b/vlib/v/checker/checker.v
index 15fe11d9cf..d271a449dc 100644
--- a/vlib/v/checker/checker.v
+++ b/vlib/v/checker/checker.v
@@ -1654,10 +1654,15 @@ pub fn (mut c Checker) check_or_expr(or_expr ast.OrExpr, ret_type table.Type) {
 				if type_fits || is_panic_or_exit {
 					return
 				}
-				type_name := c.table.type_to_str(last_stmt.typ)
 				expected_type_name := c.table.type_to_str(ret_type.clear_flag(.optional))
-				c.error('wrong return type `$type_name` in the `or {}` block, expected `$expected_type_name`',
-					last_stmt.pos)
+				if last_stmt.typ == table.void_type {
+					c.error('`or` block must provide a default value of type `$expected_type_name`, or return/exit/continue/break/panic',
+						last_stmt.pos)
+				} else {
+					type_name := c.table.type_to_str(last_stmt.typ)
+					c.error('wrong return type `$type_name` in the `or {}` block, expected `$expected_type_name`',
+						last_stmt.pos)
+				}
 				return
 			}
 			ast.BranchStmt {