From 9fbb9956dd9aa14d5999bac994e4dbbc60cc9b4b Mon Sep 17 00:00:00 2001
From: Nicholas Molnar <65710+neekolas@users.noreply.github.com>
Date: Wed, 30 Aug 2023 20:04:41 -0700
Subject: [PATCH 1/3] fix: topic non-determinism

---
 src/keystore/InMemoryKeystore.ts       |  9 +++----
 test/keystore/InMemoryKeystore.test.ts | 34 +++++++++++++++++++++++++-
 2 files changed, 37 insertions(+), 6 deletions(-)

diff --git a/src/keystore/InMemoryKeystore.ts b/src/keystore/InMemoryKeystore.ts
index 0407930e..4b6a5cc9 100644
--- a/src/keystore/InMemoryKeystore.ts
+++ b/src/keystore/InMemoryKeystore.ts
@@ -273,17 +273,16 @@ export default class InMemoryKeystore implements Keystore {
       }
       const created = nsToDate(req.createdNs)
       const recipient = toSignedPublicKeyBundle(req.recipient)
+      const myAddress = await this.getAccountAddress()
+      const theirAddress = await recipient.walletSignatureAddress()
 
       const secret = await this.v2Keys.sharedSecret(
         recipient,
         this.v2Keys.getCurrentPreKey().publicKey,
-        false
+        myAddress > theirAddress
       )
 
-      const sortedAddresses = [
-        this.accountAddress,
-        await recipient.walletSignatureAddress(),
-      ].sort()
+      const sortedAddresses = [myAddress, theirAddress].sort()
 
       const msgString =
         (req.context?.conversationId || '') + sortedAddresses.join()
diff --git a/test/keystore/InMemoryKeystore.test.ts b/test/keystore/InMemoryKeystore.test.ts
index 5d296f33..e93a2461 100644
--- a/test/keystore/InMemoryKeystore.test.ts
+++ b/test/keystore/InMemoryKeystore.test.ts
@@ -616,7 +616,39 @@ describe('InMemoryKeystore', () => {
       ).toHaveLength(25)
     })
 
-    it('works with persistence', async () => {})
+    it('creates deterministic topics bidirectionally', async () => {
+      const aliceInvite = await aliceKeystore.createInvite({
+        recipient: SignedPublicKeyBundle.fromLegacyBundle(
+          bobKeys.getPublicKeyBundle()
+        ),
+        createdNs: dateToNs(new Date()),
+        context: undefined,
+      })
+      const bobInvite = await bobKeystore.createInvite({
+        recipient: SignedPublicKeyBundle.fromLegacyBundle(
+          aliceKeys.getPublicKeyBundle()
+        ),
+        createdNs: dateToNs(new Date()),
+        context: undefined,
+      })
+      expect(
+        await aliceKeys.sharedSecret(
+          bobKeys.getPublicKeyBundle(),
+          aliceKeys.getCurrentPreKey().publicKey,
+          false
+        )
+      ).toEqual(
+        await bobKeys.sharedSecret(
+          aliceKeys.getPublicKeyBundle(),
+          bobKeys.getCurrentPreKey().publicKey,
+          true
+        )
+      )
+
+      expect(aliceInvite.conversation!.topic).toEqual(
+        bobInvite.conversation!.topic
+      )
+    })
   })
 
   describe('createAuthToken', () => {

From 4785676903f01574b3e6e20cde9835d0eb746db4 Mon Sep 17 00:00:00 2001
From: Naomi Plasterer <naomi@xmtp.com>
Date: Thu, 31 Aug 2023 13:59:55 -0700
Subject: [PATCH 2/3] fix: switch the direction of the comparison

---
 src/keystore/InMemoryKeystore.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/keystore/InMemoryKeystore.ts b/src/keystore/InMemoryKeystore.ts
index 4b6a5cc9..dc6244a4 100644
--- a/src/keystore/InMemoryKeystore.ts
+++ b/src/keystore/InMemoryKeystore.ts
@@ -279,7 +279,7 @@ export default class InMemoryKeystore implements Keystore {
       const secret = await this.v2Keys.sharedSecret(
         recipient,
         this.v2Keys.getCurrentPreKey().publicKey,
-        myAddress > theirAddress
+        myAddress < theirAddress
       )
 
       const sortedAddresses = [myAddress, theirAddress].sort()

From d0863cf90400c883890abc378809bb613794dd30 Mon Sep 17 00:00:00 2001
From: Ry Racherbaumer <ry@xmtp.com>
Date: Thu, 31 Aug 2023 16:40:33 -0500
Subject: [PATCH 3/3] test: add test for non-deterministic topic

---
 test/keystore/InMemoryKeystore.test.ts | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/test/keystore/InMemoryKeystore.test.ts b/test/keystore/InMemoryKeystore.test.ts
index e93a2461..a0a2da80 100644
--- a/test/keystore/InMemoryKeystore.test.ts
+++ b/test/keystore/InMemoryKeystore.test.ts
@@ -554,13 +554,15 @@ describe('InMemoryKeystore', () => {
           )
         ).v1!
       )
+      bobKeystore = await InMemoryKeystore.create(bobKeys)
+
       expect(await aliceKeystore.getAccountAddress()).toEqual(
         '0xF56d1F3b1290204441Cb3843C2Cac1C2f5AEd690'
       ) // alice
       expect(bobKeys.getPublicKeyBundle().walletSignatureAddress()).toEqual(
         '0x3De402A325323Bb97f00cE3ad5bFAc96A11F9A34'
       ) // bob
-      const response = await aliceKeystore.createInvite({
+      const aliceInvite = await aliceKeystore.createInvite({
         recipient: SignedPublicKeyBundle.fromLegacyBundle(
           bobKeys.getPublicKeyBundle()
         ),
@@ -570,7 +572,21 @@ describe('InMemoryKeystore', () => {
           metadata: {},
         },
       })
-      expect(response.conversation!.topic).toEqual(
+      expect(aliceInvite.conversation!.topic).toEqual(
+        '/xmtp/0/m-4b52be1e8567d72d0bc407debe2d3c7fca2ae93a47e58c3f9b5c5068aff80ec5/proto'
+      )
+
+      const bobInvite = await bobKeystore.createInvite({
+        recipient: SignedPublicKeyBundle.fromLegacyBundle(
+          aliceKeys.getPublicKeyBundle()
+        ),
+        createdNs: dateToNs(new Date()),
+        context: {
+          conversationId: 'test',
+          metadata: {},
+        },
+      })
+      expect(bobInvite.conversation!.topic).toEqual(
         '/xmtp/0/m-4b52be1e8567d72d0bc407debe2d3c7fca2ae93a47e58c3f9b5c5068aff80ec5/proto'
       )
     })