From 030087459dd9c8b58e8138345b5c70534a5f33b6 Mon Sep 17 00:00:00 2001
From: ALXD <github@alxd.org>
Date: Mon, 20 Nov 2023 14:29:06 +0100
Subject: [PATCH] expr: add tests for precise error messages

---
 tests/by-util/test_expr.rs | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/tests/by-util/test_expr.rs b/tests/by-util/test_expr.rs
index 28cfcf0ec90..18125fe99dd 100644
--- a/tests/by-util/test_expr.rs
+++ b/tests/by-util/test_expr.rs
@@ -6,6 +6,14 @@
 
 use crate::common::util::TestScenario;
 
+#[test]
+fn test_no_arguments() {
+    new_ucmd!()
+        .fails()
+        .code_is(2)
+        .stderr_only("expr: missing operand\n");
+}
+
 #[test]
 fn test_simple_values() {
     // null or 0 => EXIT_VALUE == 1
@@ -275,6 +283,12 @@ fn test_substr() {
 
 #[test]
 fn test_invalid_substr() {
+    new_ucmd!()
+        .args(&["56", "substr"])
+        .fails()
+        .code_is(2)
+        .stderr_only("expr: syntax error: unexpected argument 'substr'\n");
+
     new_ucmd!()
         .args(&["substr", "abc", "0", "1"])
         .fails()