From 87726882dd5c7e64aefa9599f944afdda0585ede Mon Sep 17 00:00:00 2001
From: katelyn martin <kmartin@fastly.com>
Date: Fri, 16 Jul 2021 14:21:31 -0400
Subject: [PATCH] =?UTF-8?q?=E2=9C=85=20add=20test=20cases=20for=20new=20`e?=
 =?UTF-8?q?ntity=5Fimpl!`=20form?=
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---
 cranelift/entity/src/lib.rs | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/cranelift/entity/src/lib.rs b/cranelift/entity/src/lib.rs
index 2665a1ce25..8cddb830dd 100644
--- a/cranelift/entity/src/lib.rs
+++ b/cranelift/entity/src/lib.rs
@@ -280,4 +280,35 @@ mod tests {
             assert_eq!(alloc::format!("{}", e), "prefix-0");
         }
     }
+
+    /// Test cases for an `EntityRef` implementation for a type we can only construct through
+    /// other means, such as calls to `core::convert::From<u32>`.
+    mod other_entity {
+        mod inner {
+            #[derive(Clone, Copy, PartialEq, Eq)]
+            pub struct InnerEntity(u32);
+
+            impl From<u32> for InnerEntity {
+                fn from(x: u32) -> Self {
+                    Self(x)
+                }
+            }
+
+            impl From<InnerEntity> for u32 {
+                fn from(x: InnerEntity) -> Self {
+                    x.0
+                }
+            }
+        }
+
+        use {crate::EntityRef, self::inner::InnerEntity};
+        entity_impl!(InnerEntity, "inner-", i, InnerEntity::from(i), u32::from(i));
+        entity_test!(InnerEntity);
+
+        #[test]
+        fn display_prefix_works() {
+            let e = InnerEntity::new(0);
+            assert_eq!(alloc::format!("{}", e), "inner-0");
+        }
+    }
 }