From 526fd424f72af34796869842b69a966ca633792b Mon Sep 17 00:00:00 2001
From: Nick Mathewson <nickm@torproject.org>
Date: Thu, 26 May 2022 12:17:29 -0400
Subject: [PATCH] Tests for tor_netdoc::util::intern

---
 crates/tor-netdoc/src/util/intern.rs | 33 ++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/crates/tor-netdoc/src/util/intern.rs b/crates/tor-netdoc/src/util/intern.rs
index 3e662def3..48d83dfa9 100644
--- a/crates/tor-netdoc/src/util/intern.rs
+++ b/crates/tor-netdoc/src/util/intern.rs
@@ -76,3 +76,36 @@ impl<T: Hash + Eq + ?Sized> InternCache<T> {
         }
     }
 }
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn interning_by_value() {
+        // "intern" case.
+        let c: InternCache<String> = InternCache::new();
+
+        let s1 = c.intern("abc".to_string());
+        let s2 = c.intern("def".to_string());
+        let s3 = c.intern("abc".to_string());
+        assert!(Arc::ptr_eq(&s1, &s3));
+        assert!(!Arc::ptr_eq(&s1, &s2));
+        assert_eq!(s2.as_ref(), "def");
+        assert_eq!(s3.as_ref(), "abc");
+    }
+
+    #[test]
+    fn interning_by_ref() {
+        // "intern" case.
+        let c: InternCache<str> = InternCache::new();
+
+        let s1 = c.intern_ref("abc");
+        let s2 = c.intern_ref("def");
+        let s3 = c.intern_ref("abc");
+        assert!(Arc::ptr_eq(&s1, &s3));
+        assert!(!Arc::ptr_eq(&s1, &s2));
+        assert_eq!(&*s2, "def");
+        assert_eq!(&*s3, "abc");
+    }
+}