From 3eb56a61c3b18c7d059a7c8fb34b3bed2eb255c6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ernesto=20Garc=C3=ADa?= <ernestognw@gmail.com>
Date: Wed, 18 Sep 2024 18:04:31 -0600
Subject: [PATCH] Disallow empty CircularBuffer setup

---
 contracts/utils/structs/CircularBuffer.sol | 6 ++++++
 test/utils/structs/CircularBuffer.test.js  | 4 ++++
 2 files changed, 10 insertions(+)

diff --git a/contracts/utils/structs/CircularBuffer.sol b/contracts/utils/structs/CircularBuffer.sol
index ae4e082595a..1d0adf8196b 100644
--- a/contracts/utils/structs/CircularBuffer.sol
+++ b/contracts/utils/structs/CircularBuffer.sol
@@ -36,6 +36,11 @@ import {Panic} from "../Panic.sol";
  * ```
  */
 library CircularBuffer {
+    /**
+     * @dev Error emitted when trying to setup a buffer with a size of 0.
+     */
+    error InvalidBufferSize();
+
     /**
      * @dev Counts the number of items that have been pushed to the buffer. The residuo modulo _data.length indicates
      * where the next value should be stored.
@@ -61,6 +66,7 @@ library CircularBuffer {
      * Consider a large buffer size may render the function unusable.
      */
     function setup(Bytes32CircularBuffer storage self, uint256 size) internal {
+        if (size == 0) revert InvalidBufferSize();
         clear(self);
         Arrays.unsafeSetLength(self._data, size);
     }
diff --git a/test/utils/structs/CircularBuffer.test.js b/test/utils/structs/CircularBuffer.test.js
index c3d61aaa823..e79ba6923b4 100644
--- a/test/utils/structs/CircularBuffer.test.js
+++ b/test/utils/structs/CircularBuffer.test.js
@@ -18,6 +18,10 @@ describe('CircularBuffer', function () {
     Object.assign(this, await loadFixture(fixture));
   });
 
+  it('reverts on invalid setup', async function () {
+    await expect(this.mock.$setup(0, 0)).to.be.revertedWithCustomError(this.mock, 'InvalidBufferSize');
+  });
+
   it('starts empty', async function () {
     expect(await this.mock.$count(0)).to.equal(0n);
     expect(await this.mock.$length(0)).to.equal(LENGTH);