Preparation for efficient consecutive burns 2 (#449)

chiru-labs · Feb 16, 2023 · 249ca1f · 249ca1f
1 parent b97b199
commit 249ca1f
Show file tree

Hide file tree

Showing 2 changed files with 12 additions and 5 deletions.
diff --git a/contracts/ERC721A.sol b/contracts/ERC721A.sol
@@ -480,11 +480,14 @@ contract ERC721A is IERC721A {
      *
      * Tokens start existing when they are minted. See {_mint}.
      */
-    function _exists(uint256 tokenId) internal view virtual returns (bool) {
-        return
-            _startTokenId() <= tokenId &&
-            tokenId < _currentIndex && // If within bounds,
-            _packedOwnerships[tokenId] & _BITMASK_BURNED == 0; // and not burned.
+    function _exists(uint256 tokenId) internal view virtual returns (bool result) {
+        if (_startTokenId() <= tokenId) {
+            if (tokenId < _currentIndex) {
+                uint256 packed;
+                while ((packed = _packedOwnerships[tokenId]) == 0) --tokenId;
+                result = packed & _BITMASK_BURNED == 0;
+            }
+        }
     }
 
     /**

diff --git a/test/ERC721A.test.js b/test/ERC721A.test.js
@@ -715,6 +715,10 @@ const createTestSuite = ({ contract, constructorArgs }) =>
             if (3 <= i && i < 3 + 2) {
               await expect(this.erc721a.ownerOf(this.startTokenId + i))
                 .to.be.revertedWith('OwnerQueryForNonexistentToken');
+              await expect(this.erc721a.getApproved(this.startTokenId + i))
+                .to.be.revertedWith('ApprovalQueryForNonexistentToken');
+              await expect(this.erc721a.tokenURI(this.startTokenId + i))
+                .to.be.revertedWith('URIQueryForNonexistentToken');
             } else {
               expect(await this.erc721a.ownerOf(this.startTokenId + i)).to.eq(owner.address);  
             }