Fix .gitignore: stop tracking ignored files

2026-05-27 03:36:32 +00:00 · 2025-07-27 10:39:02 +05:30
parent b42747e9a3
commit 3a87ef0576
625 changed files with 88566 additions and 63 deletions
@@ -0,0 +1,73 @@
+// SPDX-License-Identifier: MIT
+// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/extensions/ERC20Wrapper.sol)
+
+pragma solidity ^0.8.0;
+
+import "../ERC20.sol";
+import "../utils/SafeERC20.sol";
+
+/**
+ * @dev Extension of the ERC20 token contract to support token wrapping.
+ *
+ * Users can deposit and withdraw "underlying tokens" and receive a matching number of "wrapped tokens". This is useful
+ * in conjunction with other modules. For example, combining this wrapping mechanism with {ERC20Votes} will allow the
+ * wrapping of an existing "basic" ERC20 into a governance token.
+ *
+ * _Available since v4.2._
+ */
+abstract contract ERC20Wrapper is ERC20 {
+    IERC20 private immutable _underlying;
+
+    constructor(IERC20 underlyingToken) {
+        require(underlyingToken != this, "ERC20Wrapper: cannot self wrap");
+        _underlying = underlyingToken;
+    }
+
+    /**
+     * @dev See {ERC20-decimals}.
+     */
+    function decimals() public view virtual override returns (uint8) {
+        try IERC20Metadata(address(_underlying)).decimals() returns (uint8 value) {
+            return value;
+        } catch {
+            return super.decimals();
+        }
+    }
+
+    /**
+     * @dev Returns the address of the underlying ERC-20 token that is being wrapped.
+     */
+    function underlying() public view returns (IERC20) {
+        return _underlying;
+    }
+
+    /**
+     * @dev Allow a user to deposit underlying tokens and mint the corresponding number of wrapped tokens.
+     */
+    function depositFor(address account, uint256 amount) public virtual returns (bool) {
+        address sender = _msgSender();
+        require(sender != address(this), "ERC20Wrapper: wrapper can't deposit");
+        SafeERC20.safeTransferFrom(_underlying, sender, address(this), amount);
+        _mint(account, amount);
+        return true;
+    }
+
+    /**
+     * @dev Allow a user to burn a number of wrapped tokens and withdraw the corresponding number of underlying tokens.
+     */
+    function withdrawTo(address account, uint256 amount) public virtual returns (bool) {
+        _burn(_msgSender(), amount);
+        SafeERC20.safeTransfer(_underlying, account, amount);
+        return true;
+    }
+
+    /**
+     * @dev Mint wrapped token to cover any underlyingTokens that would have been transferred by mistake. Internal
+     * function that can be exposed with access control if desired.
+     */
+    function _recover(address account) internal virtual returns (uint256) {
+        uint256 value = _underlying.balanceOf(address(this)) - totalSupply();
+        _mint(account, value);
+        return value;
+    }
+}