From e38cdd40f9ac80eb569a8af3c7721d0624172e79 Mon Sep 17 00:00:00 2001
From: David <david@taiko.xyz>
Date: Fri, 25 Nov 2022 13:22:31 +0800
Subject: [PATCH] feat(protocol): add `TaikoL1.getBlockProvers`

---
 packages/protocol/contracts/L1/TaikoL1.sol |  8 ++++++++
 packages/protocol/test/L1/TaikoL1.test.ts  | 13 +++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/packages/protocol/contracts/L1/TaikoL1.sol b/packages/protocol/contracts/L1/TaikoL1.sol
index fefbb69b2c2..3d3e90b6f18 100644
--- a/packages/protocol/contracts/L1/TaikoL1.sol
+++ b/packages/protocol/contracts/L1/TaikoL1.sol
@@ -229,6 +229,14 @@ contract TaikoL1 is EssentialContract, IHeaderSync, V1Events {
         return LibAnchorSignature.signTransaction(hash, k);
     }
 
+    function getBlockProvers(uint256 id, bytes32 parentHash)
+        public
+        view
+        returns (address[] memory)
+    {
+        return state.forkChoices[id][parentHash].provers;
+    }
+
     function getConstants()
         public
         pure
diff --git a/packages/protocol/test/L1/TaikoL1.test.ts b/packages/protocol/test/L1/TaikoL1.test.ts
index 652618b3e7f..2a08f5e833d 100644
--- a/packages/protocol/test/L1/TaikoL1.test.ts
+++ b/packages/protocol/test/L1/TaikoL1.test.ts
@@ -94,6 +94,19 @@ describe("TaikoL1", function () {
             expect(hash).to.be.eq(genesisHash)
         })
     })
+
+    describe("getBlockProvers()", async function () {
+        it("should return empty list when there is no proof for that block", async function () {
+            const { taikoL1 } = await deployTaikoL1Fixture()
+
+            const provers = await taikoL1.getBlockProvers(
+                Math.ceil(Math.random() * 1024),
+                randomBytes32()
+            )
+
+            expect(provers).to.be.empty
+        })
+    })
 })
 
 function randomBytes32() {