From 6e4b635ee720312be6631dee4f24fdd3c066f2eb Mon Sep 17 00:00:00 2001
From: jxom <7336481+jxom@users.noreply.github.com>
Date: Mon, 18 Nov 2024 13:52:55 +1100
Subject: [PATCH] feat: derive eip-712 type

---
 .changeset/thin-drinks-matter.md |  5 +++++
 src/core/TypedData.ts            |  4 ++--
 src/core/_test/TypedData.test.ts | 10 +++++-----
 3 files changed, 12 insertions(+), 7 deletions(-)
 create mode 100644 .changeset/thin-drinks-matter.md

diff --git a/.changeset/thin-drinks-matter.md b/.changeset/thin-drinks-matter.md
new file mode 100644
index 00000000..d435e490
--- /dev/null
+++ b/.changeset/thin-drinks-matter.md
@@ -0,0 +1,5 @@
+---
+"ox": patch
+---
+
+Derive EIP-712 Domain type if not provided in `TypedData.serialize`.
diff --git a/src/core/TypedData.ts b/src/core/TypedData.ts
index f9775752..2ebc1bf8 100644
--- a/src/core/TypedData.ts
+++ b/src/core/TypedData.ts
@@ -630,9 +630,9 @@ export function serialize<
   }
 
   const domain = (() => {
-    if (!types.EIP712Domain) return {}
     if (!domain_) return {}
-    return normalizeData(types.EIP712Domain, domain_)
+    const type = types.EIP712Domain ?? extractEip712DomainTypes(domain_)
+    return normalizeData(type, domain_)
   })()
 
   const message = (() => {
diff --git a/src/core/_test/TypedData.test.ts b/src/core/_test/TypedData.test.ts
index 73227fa2..7c217a64 100644
--- a/src/core/_test/TypedData.test.ts
+++ b/src/core/_test/TypedData.test.ts
@@ -979,7 +979,7 @@ describe('serialize', () => {
         },
       }),
     ).toMatchInlineSnapshot(
-      `"{"domain":{},"message":{"address":"0xb9cab4f0e46f7f6b1024b5a7463734fa68e633f9","name":"jxom","foo":"0xb9CAB4F0E46F7F6b1024b5A7463734fa68E633f9"},"primaryType":"Foo","types":{"Foo":[{"name":"address","type":"address"},{"name":"name","type":"string"},{"name":"foo","type":"string"}]}}"`,
+      `"{"domain":{"name":"Ether!","version":"1","chainId":1,"verifyingContract":"0xcccccccccccccccccccccccccccccccccccccccc"},"message":{"address":"0xb9cab4f0e46f7f6b1024b5a7463734fa68e633f9","name":"jxom","foo":"0xb9CAB4F0E46F7F6b1024b5A7463734fa68E633f9"},"primaryType":"Foo","types":{"Foo":[{"name":"address","type":"address"},{"name":"name","type":"string"},{"name":"foo","type":"string"}]}}"`,
     )
   })
 
@@ -1444,6 +1444,10 @@ test('InvalidPrimaryTypeError', () => {
 test('exports', () => {
   expect(Object.keys(TypedData)).toMatchInlineSnapshot(`
     [
+      "BytesSizeMismatchError",
+      "InvalidDomainError",
+      "InvalidPrimaryTypeError",
+      "InvalidStructTypeError",
       "assert",
       "domainSeparator",
       "encode",
@@ -1454,10 +1458,6 @@ test('exports', () => {
       "hashStruct",
       "serialize",
       "validate",
-      "BytesSizeMismatchError",
-      "InvalidDomainError",
-      "InvalidPrimaryTypeError",
-      "InvalidStructTypeError",
       "encodeData",
       "hashType",
       "encodeField",