From 6148caed7a6d5742a263d8eafffcf1fcd49405a8 Mon Sep 17 00:00:00 2001
From: Moritz Firsching <firsching@google.com>
Date: Mon, 18 Nov 2024 17:11:58 +0100
Subject: [PATCH] Change tests for pattern-matching exercise (#2463)

to catch wrong `right == 0` checks.

To change the number like this catches for example a wrong
implementation only looking if `right_result` is zero, but not checking
if we are doing a division.
---
 src/pattern-matching/exercise.rs | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/src/pattern-matching/exercise.rs b/src/pattern-matching/exercise.rs
index 501b22360a0..f296296a4a4 100644
--- a/src/pattern-matching/exercise.rs
+++ b/src/pattern-matching/exercise.rs
@@ -111,6 +111,34 @@ fn test_recursion() {
     );
 }
 
+#[test]
+fn test_zeros() {
+    assert_eq!(
+        eval(Expression::Op {
+            op: Operation::Add,
+            left: Box::new(Expression::Value(0)),
+            right: Box::new(Expression::Value(0))
+        }),
+        Ok(0)
+    );
+    assert_eq!(
+        eval(Expression::Op {
+            op: Operation::Mul,
+            left: Box::new(Expression::Value(0)),
+            right: Box::new(Expression::Value(0))
+        }),
+        Ok(0)
+    );
+    assert_eq!(
+        eval(Expression::Op {
+            op: Operation::Sub,
+            left: Box::new(Expression::Value(0)),
+            right: Box::new(Expression::Value(0))
+        }),
+        Ok(0)
+    );
+}
+
 #[test]
 fn test_error() {
     assert_eq!(