From 8e5a53bc0df48894265199c488d25ba3ff7051da Mon Sep 17 00:00:00 2001
From: Stephen Chung <Stephen.Chung@intexact.com>
Date: Thu, 12 Nov 2020 21:53:26 +0800
Subject: [PATCH] Implement Hash for Dynamic.

---
 src/ast.rs     |  1 +
 src/dynamic.rs | 34 ++++++++++++++++++++++++++++++++++
 2 files changed, 35 insertions(+)

diff --git a/src/ast.rs b/src/ast.rs
index d99e6a74..1d5fbc70 100644
--- a/src/ast.rs
+++ b/src/ast.rs
@@ -836,6 +836,7 @@ pub struct FloatWrapper(pub FLOAT);
 impl Hash for FloatWrapper {
     #[inline(always)]
     fn hash<H: Hasher>(&self, state: &mut H) {
+        TypeId::of::<FLOAT>().hash(state);
         state.write(&self.0.to_le_bytes());
     }
 }
diff --git a/src/dynamic.rs b/src/dynamic.rs
index 6b3cc8b1..a66cc96b 100644
--- a/src/dynamic.rs
+++ b/src/dynamic.rs
@@ -21,6 +21,7 @@ use crate::stdlib::{
     any::{type_name, Any, TypeId},
     boxed::Box,
     fmt,
+    hash::{Hash, Hasher},
     ops::{Deref, DerefMut},
     string::{String, ToString},
 };
@@ -361,6 +362,39 @@ impl Dynamic {
     }
 }
 
+impl Hash for Dynamic {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        match &self.0 {
+            Union::Unit(_) => ().hash(state),
+            Union::Bool(value) => value.hash(state),
+            Union::Str(s) => s.hash(state),
+            Union::Char(ch) => ch.hash(state),
+            Union::Int(i) => i.hash(state),
+            #[cfg(not(feature = "no_float"))]
+            Union::Float(f) => {
+                TypeId::of::<FLOAT>().hash(state);
+                state.write(&f.to_le_bytes());
+            }
+            #[cfg(not(feature = "no_index"))]
+            Union::Array(a) => a.hash(state),
+            #[cfg(not(feature = "no_object"))]
+            Union::Map(m) => m.iter().for_each(|(key, item)| {
+                key.hash(state);
+                item.hash(state);
+            }),
+
+            #[cfg(not(feature = "no_closure"))]
+            #[cfg(not(feature = "sync"))]
+            Union::Shared(cell) => (*cell.borrow()).hash(state),
+            #[cfg(not(feature = "no_closure"))]
+            #[cfg(feature = "sync")]
+            Union::Shared(cell) => (*cell.read().unwrap()).hash(hasher),
+
+            _ => unimplemented!(),
+        }
+    }
+}
+
 /// Map the name of a standard type into a friendly form.
 #[inline]
 pub(crate) fn map_std_type_name(name: &str) -> &str {