fix(primitives): make sure DefaultHashBuilder implements Clone

alloy-rs · Sep 25, 2024 · c106571 · c106571
1 parent 6e24f46
commit c106571
Showing 1 changed file with 37 additions and 1 deletion.
diff --git a/crates/primitives/src/map/mod.rs b/crates/primitives/src/map/mod.rs
@@ -63,7 +63,27 @@ cfg_if! {
 
         cfg_if! {
             if #[cfg(all(feature = "std", feature = "rand"))] {
-                use rustc_hash::FxRandomState as FxBuildHasherInner;
+                // use rustc_hash::FxRandomState as FxBuildHasherInner;
+
+                // TODO: Polyfill for https://github.com/rust-lang/rustc-hash/pull/52/
+                #[derive(Default)]
+                #[allow(missing_debug_implementations)]
+                #[doc(hidden)]
+                pub struct FxBuildHasherInner(rustc_hash::FxRandomState);
+
+                impl Clone for FxBuildHasherInner {
+                    fn clone(&self) -> Self {
+                        Self(Default::default())
+                    }
+                }
+
+                impl core::hash::BuildHasher for FxBuildHasherInner {
+                    type Hasher = rustc_hash::FxHasher;
+
+                    fn build_hasher(&self) -> Self::Hasher {
+                        self.0.build_hasher()
+                    }
+                }
             } else {
                 use rustc_hash::FxBuildHasher as FxBuildHasherInner;
             }
@@ -127,3 +147,19 @@ cfg_if! {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn default_hasher_builder_traits() {
+        let hash_builder = <DefaultHashBuilder as Default>::default();
+        let _hash_builder2 = <DefaultHashBuilder as Clone>::clone(&hash_builder);
+        let mut hasher =
+            <DefaultHashBuilder as core::hash::BuildHasher>::build_hasher(&hash_builder);
+
+        <DefaultHasher as core::hash::Hasher>::write_u8(&mut hasher, 0);
+        let _hasher2 = <DefaultHasher as Clone>::clone(&hasher);
+    }
+}