{ "fileName": "SafeERC20.sol", "contractName": "SafeERC20", "source": "// SPDX-License-Identifier: MIT\n\npragma solidity ^0.7.0;\n\nimport \"./IERC20.sol\";\nimport \"../../math/SafeMath.sol\";\nimport \"../../utils/Address.sol\";\n\n/**\n * @title SafeERC20\n * @dev Wrappers around ERC20 operations that throw on failure (when the token\n * contract returns false). Tokens that return no value (and instead revert or\n * throw on failure) are also supported, non-reverting calls are assumed to be\n * successful.\n * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,\n * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.\n */\nlibrary SafeERC20 {\n using SafeMath for uint256;\n using Address for address;\n\n function safeTransfer(IERC20 token, address to, uint256 value) internal {\n _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));\n }\n\n function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {\n _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));\n }\n\n /**\n * @dev Deprecated. This function has issues similar to the ones found in\n * {IERC20-approve}, and its usage is discouraged.\n *\n * Whenever possible, use {safeIncreaseAllowance} and\n * {safeDecreaseAllowance} instead.\n */\n function safeApprove(IERC20 token, address spender, uint256 value) internal {\n // safeApprove should only be called when setting an initial allowance,\n // or when resetting it to zero. To increase and decrease it, use\n // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'\n // solhint-disable-next-line max-line-length\n require((value == 0) || (token.allowance(address(this), spender) == 0),\n \"SafeERC20: approve from non-zero to non-zero allowance\"\n );\n _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));\n }\n\n function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {\n uint256 newAllowance = token.allowance(address(this), spender).add(value);\n _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));\n }\n\n function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {\n uint256 newAllowance = token.allowance(address(this), spender).sub(value, \"SafeERC20: decreased allowance below zero\");\n _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));\n }\n\n /**\n * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement\n * on the return value: the return value is optional (but if data is returned, it must not be false).\n * @param token The token targeted by the call.\n * @param data The call data (encoded using abi.encode or one of its variants).\n */\n function _callOptionalReturn(IERC20 token, bytes memory data) private {\n // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since\n // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that\n // the target address contains contract code and also asserts for success in the low-level call.\n\n bytes memory returndata = address(token).functionCall(data, \"SafeERC20: low-level call failed\");\n if (returndata.length > 0) { // Return data is optional\n // solhint-disable-next-line max-line-length\n require(abi.decode(returndata, (bool)), \"SafeERC20: ERC20 operation did not succeed\");\n }\n }\n}\n", "sourcePath": "contracts/token/ERC20/SafeERC20.sol", "sourceMap": "608:3104:90:-:0;;;;;;;;;;;;;;;;;;;;;;;;;", "deployedSourceMap": "608:3104:90:-:0;;;;;;;;", "abi": [], "ast": { "absolutePath": "contracts/token/ERC20/SafeERC20.sol", "exportedSymbols": { "SafeERC20": [ 9992 ] }, "id": 9993, "license": "MIT", "nodeType": "SourceUnit", "nodes": [ { "id": 9781, "literals": [ "solidity", "^", "0.7", ".0" ], "nodeType": "PragmaDirective", "src": "33:23:90" }, { "absolutePath": "contracts/token/ERC20/IERC20.sol", "file": "./IERC20.sol", "id": 9782, "nodeType": "ImportDirective", "scope": 9993, "sourceUnit": 9780, "src": "58:22:90", "symbolAliases": [], "unitAlias": "" }, { "absolutePath": "contracts/math/SafeMath.sol", "file": "../../math/SafeMath.sol", "id": 9783, "nodeType": "ImportDirective", "scope": 9993, "sourceUnit": 2422, "src": "81:33:90", "symbolAliases": [], "unitAlias": "" }, { "absolutePath": "contracts/utils/Address.sol", "file": "../../utils/Address.sol", "id": 9784, "nodeType": "ImportDirective", "scope": 9993, "sourceUnit": 12812, "src": "115:33:90", "symbolAliases": [], "unitAlias": "" }, { "abstract": false, "baseContracts": [], "contractDependencies": [], "contractKind": "library", "documentation": { "id": 9785, "nodeType": "StructuredDocumentation", "src": "150:457:90", "text": " @title SafeERC20\n @dev Wrappers around ERC20 operations that throw on failure (when the token\n contract returns false). Tokens that return no value (and instead revert or\n throw on failure) are also supported, non-reverting calls are assumed to be\n successful.\n To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,\n which allows you to call the safe operations as `token.safeTransfer(...)`, etc." }, "fullyImplemented": true, "id": 9992, "linearizedBaseContracts": [ 9992 ], "name": "SafeERC20", "nodeType": "ContractDefinition", "nodes": [ { "id": 9788, "libraryName": { "contractScope": null, "id": 9786, "name": "SafeMath", "nodeType": "UserDefinedTypeName", "referencedDeclaration": 2421, "src": "638:8:90", "typeDescriptions": { "typeIdentifier": "t_contract$_SafeMath_$2421", "typeString": "library SafeMath" } }, "nodeType": "UsingForDirective", "src": "632:27:90", "typeName": { "id": 9787, "name": "uint256", "nodeType": "ElementaryTypeName", "src": "651:7:90", "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" } } }, { "id": 9791, "libraryName": { "contractScope": null, "id": 9789, "name": "Address", "nodeType": "UserDefinedTypeName", "referencedDeclaration": 12811, "src": "670:7:90", "typeDescriptions": { "typeIdentifier": "t_contract$_Address_$12811", "typeString": "library Address" } }, "nodeType": "UsingForDirective", "src": "664:26:90", "typeName": { "id": 9790, "name": "address", "nodeType": "ElementaryTypeName", "src": "682:7:90", "stateMutability": "nonpayable", "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" } } }, { "body": { "id": 9812, "nodeType": "Block", "src": "768:103:90", "statements": [ { "expression": { "argumentTypes": null, "arguments": [ { "argumentTypes": null, "id": 9801, "name": "token", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9793, "src": "798:5:90", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" } }, { "argumentTypes": null, "arguments": [ { "argumentTypes": null, "expression": { "argumentTypes": null, "expression": { "argumentTypes": null, "id": 9804, "name": "token", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9793, "src": "828:5:90", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" } }, "id": 9805, "isConstant": false, "isLValue": false, "isPure": false, "lValueRequested": false, "memberName": "transfer", "nodeType": "MemberAccess", "referencedDeclaration": 9728, "src": "828:14:90", "typeDescriptions": { "typeIdentifier": "t_function_external_nonpayable$_t_address_$_t_uint256_$returns$_t_bool_$", "typeString": "function (address,uint256) external returns (bool)" } }, "id": 9806, "isConstant": false, "isLValue": false, "isPure": false, "lValueRequested": false, "memberName": "selector", "nodeType": "MemberAccess", "referencedDeclaration": null, "src": "828:23:90", "typeDescriptions": { "typeIdentifier": "t_bytes4", "typeString": "bytes4" } }, { "argumentTypes": null, "id": 9807, "name": "to", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9795, "src": "853:2:90", "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" } }, { "argumentTypes": null, "id": 9808, "name": "value", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9797, "src": "857:5:90", "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" } } ], "expression": { "argumentTypes": [ { "typeIdentifier": "t_bytes4", "typeString": "bytes4" }, { "typeIdentifier": "t_address", "typeString": "address" }, { "typeIdentifier": "t_uint256", "typeString": "uint256" } ], "expression": { "argumentTypes": null, "id": 9802, "name": "abi", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": -1, "src": "805:3:90", "typeDescriptions": { "typeIdentifier": "t_magic_abi", "typeString": "abi" } }, "id": 9803, "isConstant": false, "isLValue": false, "isPure": true, "lValueRequested": false, "memberName": "encodeWithSelector", "nodeType": "MemberAccess", "referencedDeclaration": null, "src": "805:22:90", "typeDescriptions": { "typeIdentifier": "t_function_abiencodewithselector_pure$_t_bytes4_$returns$_t_bytes_memory_ptr_$", "typeString": "function (bytes4) pure returns (bytes memory)" } }, "id": 9809, "isConstant": false, "isLValue": false, "isPure": false, "kind": "functionCall", "lValueRequested": false, "names": [], "nodeType": "FunctionCall", "src": "805:58:90", "tryCall": false, "typeDescriptions": { "typeIdentifier": "t_bytes_memory_ptr", "typeString": "bytes memory" } } ], "expression": { "argumentTypes": [ { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" }, { "typeIdentifier": "t_bytes_memory_ptr", "typeString": "bytes memory" } ], "id": 9800, "name": "_callOptionalReturn", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9991, "src": "778:19:90", "typeDescriptions": { "typeIdentifier": "t_function_internal_nonpayable$_t_contract$_IERC20_$9779_$_t_bytes_memory_ptr_$returns$__$", "typeString": "function (contract IERC20,bytes memory)" } }, "id": 9810, "isConstant": false, "isLValue": false, "isPure": false, "kind": "functionCall", "lValueRequested": false, "names": [], "nodeType": "FunctionCall", "src": "778:86:90", "tryCall": false, "typeDescriptions": { "typeIdentifier": "t_tuple$__$", "typeString": "tuple()" } }, "id": 9811, "nodeType": "ExpressionStatement", "src": "778:86:90" } ] }, "documentation": null, "id": 9813, "implemented": true, "kind": "function", "modifiers": [], "name": "safeTransfer", "nodeType": "FunctionDefinition", "overrides": null, "parameters": { "id": 9798, "nodeType": "ParameterList", "parameters": [ { "constant": false, "id": 9793, "mutability": "mutable", "name": "token", "nodeType": "VariableDeclaration", "overrides": null, "scope": 9813, "src": "718:12:90", "stateVariable": false, "storageLocation": "default", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" }, "typeName": { "contractScope": null, "id": 9792, "name": "IERC20", "nodeType": "UserDefinedTypeName", "referencedDeclaration": 9779, "src": "718:6:90", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" } }, "value": null, "visibility": "internal" }, { "constant": false, "id": 9795, "mutability": "mutable", "name": "to", "nodeType": "VariableDeclaration", "overrides": null, "scope": 9813, "src": "732:10:90", "stateVariable": false, "storageLocation": "default", "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" }, "typeName": { "id": 9794, "name": "address", "nodeType": "ElementaryTypeName", "src": "732:7:90", "stateMutability": "nonpayable", "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" } }, "value": null, "visibility": "internal" }, { "constant": false, "id": 9797, "mutability": "mutable", "name": "value", "nodeType": "VariableDeclaration", "overrides": null, "scope": 9813, "src": "744:13:90", "stateVariable": false, "storageLocation": "default", "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" }, "typeName": { "id": 9796, "name": "uint256", "nodeType": "ElementaryTypeName", "src": "744:7:90", "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" } }, "value": null, "visibility": "internal" } ], "src": "717:41:90" }, "returnParameters": { "id": 9799, "nodeType": "ParameterList", "parameters": [], "src": "768:0:90" }, "scope": 9992, "src": "696:175:90", "stateMutability": "nonpayable", "virtual": false, "visibility": "internal" }, { "body": { "id": 9837, "nodeType": "Block", "src": "967:113:90", "statements": [ { "expression": { "argumentTypes": null, "arguments": [ { "argumentTypes": null, "id": 9825, "name": "token", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9815, "src": "997:5:90", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" } }, { "argumentTypes": null, "arguments": [ { "argumentTypes": null, "expression": { "argumentTypes": null, "expression": { "argumentTypes": null, "id": 9828, "name": "token", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9815, "src": "1027:5:90", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" } }, "id": 9829, "isConstant": false, "isLValue": false, "isPure": false, "lValueRequested": false, "memberName": "transferFrom", "nodeType": "MemberAccess", "referencedDeclaration": 9760, "src": "1027:18:90", "typeDescriptions": { "typeIdentifier": "t_function_external_nonpayable$_t_address_$_t_address_$_t_uint256_$returns$_t_bool_$", "typeString": "function (address,address,uint256) external returns (bool)" } }, "id": 9830, "isConstant": false, "isLValue": false, "isPure": false, "lValueRequested": false, "memberName": "selector", "nodeType": "MemberAccess", "referencedDeclaration": null, "src": "1027:27:90", "typeDescriptions": { "typeIdentifier": "t_bytes4", "typeString": "bytes4" } }, { "argumentTypes": null, "id": 9831, "name": "from", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9817, "src": "1056:4:90", "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" } }, { "argumentTypes": null, "id": 9832, "name": "to", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9819, "src": "1062:2:90", "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" } }, { "argumentTypes": null, "id": 9833, "name": "value", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9821, "src": "1066:5:90", "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" } } ], "expression": { "argumentTypes": [ { "typeIdentifier": "t_bytes4", "typeString": "bytes4" }, { "typeIdentifier": "t_address", "typeString": "address" }, { "typeIdentifier": "t_address", "typeString": "address" }, { "typeIdentifier": "t_uint256", "typeString": "uint256" } ], "expression": { "argumentTypes": null, "id": 9826, "name": "abi", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": -1, "src": "1004:3:90", "typeDescriptions": { "typeIdentifier": "t_magic_abi", "typeString": "abi" } }, "id": 9827, "isConstant": false, "isLValue": false, "isPure": true, "lValueRequested": false, "memberName": "encodeWithSelector", "nodeType": "MemberAccess", "referencedDeclaration": null, "src": "1004:22:90", "typeDescriptions": { "typeIdentifier": "t_function_abiencodewithselector_pure$_t_bytes4_$returns$_t_bytes_memory_ptr_$", "typeString": "function (bytes4) pure returns (bytes memory)" } }, "id": 9834, "isConstant": false, "isLValue": false, "isPure": false, "kind": "functionCall", "lValueRequested": false, "names": [], "nodeType": "FunctionCall", "src": "1004:68:90", "tryCall": false, "typeDescriptions": { "typeIdentifier": "t_bytes_memory_ptr", "typeString": "bytes memory" } } ], "expression": { "argumentTypes": [ { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" }, { "typeIdentifier": "t_bytes_memory_ptr", "typeString": "bytes memory" } ], "id": 9824, "name": "_callOptionalReturn", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9991, "src": "977:19:90", "typeDescriptions": { "typeIdentifier": "t_function_internal_nonpayable$_t_contract$_IERC20_$9779_$_t_bytes_memory_ptr_$returns$__$", "typeString": "function (contract IERC20,bytes memory)" } }, "id": 9835, "isConstant": false, "isLValue": false, "isPure": false, "kind": "functionCall", "lValueRequested": false, "names": [], "nodeType": "FunctionCall", "src": "977:96:90", "tryCall": false, "typeDescriptions": { "typeIdentifier": "t_tuple$__$", "typeString": "tuple()" } }, "id": 9836, "nodeType": "ExpressionStatement", "src": "977:96:90" } ] }, "documentation": null, "id": 9838, "implemented": true, "kind": "function", "modifiers": [], "name": "safeTransferFrom", "nodeType": "FunctionDefinition", "overrides": null, "parameters": { "id": 9822, "nodeType": "ParameterList", "parameters": [ { "constant": false, "id": 9815, "mutability": "mutable", "name": "token", "nodeType": "VariableDeclaration", "overrides": null, "scope": 9838, "src": "903:12:90", "stateVariable": false, "storageLocation": "default", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" }, "typeName": { "contractScope": null, "id": 9814, "name": "IERC20", "nodeType": "UserDefinedTypeName", "referencedDeclaration": 9779, "src": "903:6:90", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" } }, "value": null, "visibility": "internal" }, { "constant": false, "id": 9817, "mutability": "mutable", "name": "from", "nodeType": "VariableDeclaration", "overrides": null, "scope": 9838, "src": "917:12:90", "stateVariable": false, "storageLocation": "default", "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" }, "typeName": { "id": 9816, "name": "address", "nodeType": "ElementaryTypeName", "src": "917:7:90", "stateMutability": "nonpayable", "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" } }, "value": null, "visibility": "internal" }, { "constant": false, "id": 9819, "mutability": "mutable", "name": "to", "nodeType": "VariableDeclaration", "overrides": null, "scope": 9838, "src": "931:10:90", "stateVariable": false, "storageLocation": "default", "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" }, "typeName": { "id": 9818, "name": "address", "nodeType": "ElementaryTypeName", "src": "931:7:90", "stateMutability": "nonpayable", "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" } }, "value": null, "visibility": "internal" }, { "constant": false, "id": 9821, "mutability": "mutable", "name": "value", "nodeType": "VariableDeclaration", "overrides": null, "scope": 9838, "src": "943:13:90", "stateVariable": false, "storageLocation": "default", "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" }, "typeName": { "id": 9820, "name": "uint256", "nodeType": "ElementaryTypeName", "src": "943:7:90", "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" } }, "value": null, "visibility": "internal" } ], "src": "902:55:90" }, "returnParameters": { "id": 9823, "nodeType": "ParameterList", "parameters": [], "src": "967:0:90" }, "scope": 9992, "src": "877:203:90", "stateMutability": "nonpayable", "virtual": false, "visibility": "internal" }, { "body": { "id": 9880, "nodeType": "Block", "src": "1416:537:90", "statements": [ { "expression": { "argumentTypes": null, "arguments": [ { "argumentTypes": null, "commonType": { "typeIdentifier": "t_bool", "typeString": "bool" }, "id": 9864, "isConstant": false, "isLValue": false, "isPure": false, "lValueRequested": false, "leftExpression": { "argumentTypes": null, "components": [ { "argumentTypes": null, "commonType": { "typeIdentifier": "t_uint256", "typeString": "uint256" }, "id": 9851, "isConstant": false, "isLValue": false, "isPure": false, "lValueRequested": false, "leftExpression": { "argumentTypes": null, "id": 9849, "name": "value", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9845, "src": "1705:5:90", "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" } }, "nodeType": "BinaryOperation", "operator": "==", "rightExpression": { "argumentTypes": null, "hexValue": "30", "id": 9850, "isConstant": false, "isLValue": false, "isPure": true, "kind": "number", "lValueRequested": false, "nodeType": "Literal", "src": "1714:1:90", "subdenomination": null, "typeDescriptions": { "typeIdentifier": "t_rational_0_by_1", "typeString": "int_const 0" }, "value": "0" }, "src": "1705:10:90", "typeDescriptions": { "typeIdentifier": "t_bool", "typeString": "bool" } } ], "id": 9852, "isConstant": false, "isInlineArray": false, "isLValue": false, "isPure": false, "lValueRequested": false, "nodeType": "TupleExpression", "src": "1704:12:90", "typeDescriptions": { "typeIdentifier": "t_bool", "typeString": "bool" } }, "nodeType": "BinaryOperation", "operator": "||", "rightExpression": { "argumentTypes": null, "components": [ { "argumentTypes": null, "commonType": { "typeIdentifier": "t_uint256", "typeString": "uint256" }, "id": 9862, "isConstant": false, "isLValue": false, "isPure": false, "lValueRequested": false, "leftExpression": { "argumentTypes": null, "arguments": [ { "argumentTypes": null, "arguments": [ { "argumentTypes": null, "id": 9857, "name": "this", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": -28, "src": "1745:4:90", "typeDescriptions": { "typeIdentifier": "t_contract$_SafeERC20_$9992", "typeString": "library SafeERC20" } } ], "expression": { "argumentTypes": [ { "typeIdentifier": "t_contract$_SafeERC20_$9992", "typeString": "library SafeERC20" } ], "id": 9856, "isConstant": false, "isLValue": false, "isPure": true, "lValueRequested": false, "nodeType": "ElementaryTypeNameExpression", "src": "1737:7:90", "typeDescriptions": { "typeIdentifier": "t_type$_t_address_$", "typeString": "type(address)" }, "typeName": { "id": 9855, "name": "address", "nodeType": "ElementaryTypeName", "src": "1737:7:90", "typeDescriptions": { "typeIdentifier": null, "typeString": null } } }, "id": 9858, "isConstant": false, "isLValue": false, "isPure": false, "kind": "typeConversion", "lValueRequested": false, "names": [], "nodeType": "FunctionCall", "src": "1737:13:90", "tryCall": false, "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" } }, { "argumentTypes": null, "id": 9859, "name": "spender", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9843, "src": "1752:7:90", "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" } } ], "expression": { "argumentTypes": [ { "typeIdentifier": "t_address", "typeString": "address" }, { "typeIdentifier": "t_address", "typeString": "address" } ], "expression": { "argumentTypes": null, "id": 9853, "name": "token", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9841, "src": "1721:5:90", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" } }, "id": 9854, "isConstant": false, "isLValue": false, "isPure": false, "lValueRequested": false, "memberName": "allowance", "nodeType": "MemberAccess", "referencedDeclaration": 9738, "src": "1721:15:90", "typeDescriptions": { "typeIdentifier": "t_function_external_view$_t_address_$_t_address_$returns$_t_uint256_$", "typeString": "function (address,address) view external returns (uint256)" } }, "id": 9860, "isConstant": false, "isLValue": false, "isPure": false, "kind": "functionCall", "lValueRequested": false, "names": [], "nodeType": "FunctionCall", "src": "1721:39:90", "tryCall": false, "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" } }, "nodeType": "BinaryOperation", "operator": "==", "rightExpression": { "argumentTypes": null, "hexValue": "30", "id": 9861, "isConstant": false, "isLValue": false, "isPure": true, "kind": "number", "lValueRequested": false, "nodeType": "Literal", "src": "1764:1:90", "subdenomination": null, "typeDescriptions": { "typeIdentifier": "t_rational_0_by_1", "typeString": "int_const 0" }, "value": "0" }, "src": "1721:44:90", "typeDescriptions": { "typeIdentifier": "t_bool", "typeString": "bool" } } ], "id": 9863, "isConstant": false, "isInlineArray": false, "isLValue": false, "isPure": false, "lValueRequested": false, "nodeType": "TupleExpression", "src": "1720:46:90", "typeDescriptions": { "typeIdentifier": "t_bool", "typeString": "bool" } }, "src": "1704:62:90", "typeDescriptions": { "typeIdentifier": "t_bool", "typeString": "bool" } }, { "argumentTypes": null, "hexValue": "5361666545524332303a20617070726f76652066726f6d206e6f6e2d7a65726f20746f206e6f6e2d7a65726f20616c6c6f77616e6365", "id": 9865, "isConstant": false, "isLValue": false, "isPure": true, "kind": "string", "lValueRequested": false, "nodeType": "Literal", "src": "1780:56:90", "subdenomination": null, "typeDescriptions": { "typeIdentifier": "t_stringliteral_ef945ddb1bfdc0da870feb4560d868b047642b4ac7f2fb7f8b7c51cb4a411e25", "typeString": "literal_string \"SafeERC20: approve from non-zero to non-zero allowance\"" }, "value": "SafeERC20: approve from non-zero to non-zero allowance" } ], "expression": { "argumentTypes": [ { "typeIdentifier": "t_bool", "typeString": "bool" }, { "typeIdentifier": "t_stringliteral_ef945ddb1bfdc0da870feb4560d868b047642b4ac7f2fb7f8b7c51cb4a411e25", "typeString": "literal_string \"SafeERC20: approve from non-zero to non-zero allowance\"" } ], "id": 9848, "name": "require", "nodeType": "Identifier", "overloadedDeclarations": [ -18, -18 ], "referencedDeclaration": -18, "src": "1696:7:90", "typeDescriptions": { "typeIdentifier": "t_function_require_pure$_t_bool_$_t_string_memory_ptr_$returns$__$", "typeString": "function (bool,string memory) pure" } }, "id": 9866, "isConstant": false, "isLValue": false, "isPure": false, "kind": "functionCall", "lValueRequested": false, "names": [], "nodeType": "FunctionCall", "src": "1696:150:90", "tryCall": false, "typeDescriptions": { "typeIdentifier": "t_tuple$__$", "typeString": "tuple()" } }, "id": 9867, "nodeType": "ExpressionStatement", "src": "1696:150:90" }, { "expression": { "argumentTypes": null, "arguments": [ { "argumentTypes": null, "id": 9869, "name": "token", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9841, "src": "1876:5:90", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" } }, { "argumentTypes": null, "arguments": [ { "argumentTypes": null, "expression": { "argumentTypes": null, "expression": { "argumentTypes": null, "id": 9872, "name": "token", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9841, "src": "1906:5:90", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" } }, "id": 9873, "isConstant": false, "isLValue": false, "isPure": false, "lValueRequested": false, "memberName": "approve", "nodeType": "MemberAccess", "referencedDeclaration": 9748, "src": "1906:13:90", "typeDescriptions": { "typeIdentifier": "t_function_external_nonpayable$_t_address_$_t_uint256_$returns$_t_bool_$", "typeString": "function (address,uint256) external returns (bool)" } }, "id": 9874, "isConstant": false, "isLValue": false, "isPure": false, "lValueRequested": false, "memberName": "selector", "nodeType": "MemberAccess", "referencedDeclaration": null, "src": "1906:22:90", "typeDescriptions": { "typeIdentifier": "t_bytes4", "typeString": "bytes4" } }, { "argumentTypes": null, "id": 9875, "name": "spender", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9843, "src": "1930:7:90", "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" } }, { "argumentTypes": null, "id": 9876, "name": "value", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9845, "src": "1939:5:90", "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" } } ], "expression": { "argumentTypes": [ { "typeIdentifier": "t_bytes4", "typeString": "bytes4" }, { "typeIdentifier": "t_address", "typeString": "address" }, { "typeIdentifier": "t_uint256", "typeString": "uint256" } ], "expression": { "argumentTypes": null, "id": 9870, "name": "abi", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": -1, "src": "1883:3:90", "typeDescriptions": { "typeIdentifier": "t_magic_abi", "typeString": "abi" } }, "id": 9871, "isConstant": false, "isLValue": false, "isPure": true, "lValueRequested": false, "memberName": "encodeWithSelector", "nodeType": "MemberAccess", "referencedDeclaration": null, "src": "1883:22:90", "typeDescriptions": { "typeIdentifier": "t_function_abiencodewithselector_pure$_t_bytes4_$returns$_t_bytes_memory_ptr_$", "typeString": "function (bytes4) pure returns (bytes memory)" } }, "id": 9877, "isConstant": false, "isLValue": false, "isPure": false, "kind": "functionCall", "lValueRequested": false, "names": [], "nodeType": "FunctionCall", "src": "1883:62:90", "tryCall": false, "typeDescriptions": { "typeIdentifier": "t_bytes_memory_ptr", "typeString": "bytes memory" } } ], "expression": { "argumentTypes": [ { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" }, { "typeIdentifier": "t_bytes_memory_ptr", "typeString": "bytes memory" } ], "id": 9868, "name": "_callOptionalReturn", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9991, "src": "1856:19:90", "typeDescriptions": { "typeIdentifier": "t_function_internal_nonpayable$_t_contract$_IERC20_$9779_$_t_bytes_memory_ptr_$returns$__$", "typeString": "function (contract IERC20,bytes memory)" } }, "id": 9878, "isConstant": false, "isLValue": false, "isPure": false, "kind": "functionCall", "lValueRequested": false, "names": [], "nodeType": "FunctionCall", "src": "1856:90:90", "tryCall": false, "typeDescriptions": { "typeIdentifier": "t_tuple$__$", "typeString": "tuple()" } }, "id": 9879, "nodeType": "ExpressionStatement", "src": "1856:90:90" } ] }, "documentation": { "id": 9839, "nodeType": "StructuredDocumentation", "src": "1086:249:90", "text": " @dev Deprecated. This function has issues similar to the ones found in\n {IERC20-approve}, and its usage is discouraged.\n Whenever possible, use {safeIncreaseAllowance} and\n {safeDecreaseAllowance} instead." }, "id": 9881, "implemented": true, "kind": "function", "modifiers": [], "name": "safeApprove", "nodeType": "FunctionDefinition", "overrides": null, "parameters": { "id": 9846, "nodeType": "ParameterList", "parameters": [ { "constant": false, "id": 9841, "mutability": "mutable", "name": "token", "nodeType": "VariableDeclaration", "overrides": null, "scope": 9881, "src": "1361:12:90", "stateVariable": false, "storageLocation": "default", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" }, "typeName": { "contractScope": null, "id": 9840, "name": "IERC20", "nodeType": "UserDefinedTypeName", "referencedDeclaration": 9779, "src": "1361:6:90", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" } }, "value": null, "visibility": "internal" }, { "constant": false, "id": 9843, "mutability": "mutable", "name": "spender", "nodeType": "VariableDeclaration", "overrides": null, "scope": 9881, "src": "1375:15:90", "stateVariable": false, "storageLocation": "default", "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" }, "typeName": { "id": 9842, "name": "address", "nodeType": "ElementaryTypeName", "src": "1375:7:90", "stateMutability": "nonpayable", "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" } }, "value": null, "visibility": "internal" }, { "constant": false, "id": 9845, "mutability": "mutable", "name": "value", "nodeType": "VariableDeclaration", "overrides": null, "scope": 9881, "src": "1392:13:90", "stateVariable": false, "storageLocation": "default", "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" }, "typeName": { "id": 9844, "name": "uint256", "nodeType": "ElementaryTypeName", "src": "1392:7:90", "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" } }, "value": null, "visibility": "internal" } ], "src": "1360:46:90" }, "returnParameters": { "id": 9847, "nodeType": "ParameterList", "parameters": [], "src": "1416:0:90" }, "scope": 9992, "src": "1340:613:90", "stateMutability": "nonpayable", "virtual": false, "visibility": "internal" }, { "body": { "id": 9916, "nodeType": "Block", "src": "2045:197:90", "statements": [ { "assignments": [ 9891 ], "declarations": [ { "constant": false, "id": 9891, "mutability": "mutable", "name": "newAllowance", "nodeType": "VariableDeclaration", "overrides": null, "scope": 9916, "src": "2055:20:90", "stateVariable": false, "storageLocation": "default", "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" }, "typeName": { "id": 9890, "name": "uint256", "nodeType": "ElementaryTypeName", "src": "2055:7:90", "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" } }, "value": null, "visibility": "internal" } ], "id": 9903, "initialValue": { "argumentTypes": null, "arguments": [ { "argumentTypes": null, "id": 9901, "name": "value", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9887, "src": "2122:5:90", "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" } } ], "expression": { "argumentTypes": [ { "typeIdentifier": "t_uint256", "typeString": "uint256" } ], "expression": { "argumentTypes": null, "arguments": [ { "argumentTypes": null, "arguments": [ { "argumentTypes": null, "id": 9896, "name": "this", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": -28, "src": "2102:4:90", "typeDescriptions": { "typeIdentifier": "t_contract$_SafeERC20_$9992", "typeString": "library SafeERC20" } } ], "expression": { "argumentTypes": [ { "typeIdentifier": "t_contract$_SafeERC20_$9992", "typeString": "library SafeERC20" } ], "id": 9895, "isConstant": false, "isLValue": false, "isPure": true, "lValueRequested": false, "nodeType": "ElementaryTypeNameExpression", "src": "2094:7:90", "typeDescriptions": { "typeIdentifier": "t_type$_t_address_$", "typeString": "type(address)" }, "typeName": { "id": 9894, "name": "address", "nodeType": "ElementaryTypeName", "src": "2094:7:90", "typeDescriptions": { "typeIdentifier": null, "typeString": null } } }, "id": 9897, "isConstant": false, "isLValue": false, "isPure": false, "kind": "typeConversion", "lValueRequested": false, "names": [], "nodeType": "FunctionCall", "src": "2094:13:90", "tryCall": false, "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" } }, { "argumentTypes": null, "id": 9898, "name": "spender", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9885, "src": "2109:7:90", "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" } } ], "expression": { "argumentTypes": [ { "typeIdentifier": "t_address", "typeString": "address" }, { "typeIdentifier": "t_address", "typeString": "address" } ], "expression": { "argumentTypes": null, "id": 9892, "name": "token", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9883, "src": "2078:5:90", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" } }, "id": 9893, "isConstant": false, "isLValue": false, "isPure": false, "lValueRequested": false, "memberName": "allowance", "nodeType": "MemberAccess", "referencedDeclaration": 9738, "src": "2078:15:90", "typeDescriptions": { "typeIdentifier": "t_function_external_view$_t_address_$_t_address_$returns$_t_uint256_$", "typeString": "function (address,address) view external returns (uint256)" } }, "id": 9899, "isConstant": false, "isLValue": false, "isPure": false, "kind": "functionCall", "lValueRequested": false, "names": [], "nodeType": "FunctionCall", "src": "2078:39:90", "tryCall": false, "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" } }, "id": 9900, "isConstant": false, "isLValue": false, "isPure": false, "lValueRequested": false, "memberName": "add", "nodeType": "MemberAccess", "referencedDeclaration": 2254, "src": "2078:43:90", "typeDescriptions": { "typeIdentifier": "t_function_internal_pure$_t_uint256_$_t_uint256_$returns$_t_uint256_$bound_to$_t_uint256_$", "typeString": "function (uint256,uint256) pure returns (uint256)" } }, "id": 9902, "isConstant": false, "isLValue": false, "isPure": false, "kind": "functionCall", "lValueRequested": false, "names": [], "nodeType": "FunctionCall", "src": "2078:50:90", "tryCall": false, "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" } }, "nodeType": "VariableDeclarationStatement", "src": "2055:73:90" }, { "expression": { "argumentTypes": null, "arguments": [ { "argumentTypes": null, "id": 9905, "name": "token", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9883, "src": "2158:5:90", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" } }, { "argumentTypes": null, "arguments": [ { "argumentTypes": null, "expression": { "argumentTypes": null, "expression": { "argumentTypes": null, "id": 9908, "name": "token", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9883, "src": "2188:5:90", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" } }, "id": 9909, "isConstant": false, "isLValue": false, "isPure": false, "lValueRequested": false, "memberName": "approve", "nodeType": "MemberAccess", "referencedDeclaration": 9748, "src": "2188:13:90", "typeDescriptions": { "typeIdentifier": "t_function_external_nonpayable$_t_address_$_t_uint256_$returns$_t_bool_$", "typeString": "function (address,uint256) external returns (bool)" } }, "id": 9910, "isConstant": false, "isLValue": false, "isPure": false, "lValueRequested": false, "memberName": "selector", "nodeType": "MemberAccess", "referencedDeclaration": null, "src": "2188:22:90", "typeDescriptions": { "typeIdentifier": "t_bytes4", "typeString": "bytes4" } }, { "argumentTypes": null, "id": 9911, "name": "spender", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9885, "src": "2212:7:90", "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" } }, { "argumentTypes": null, "id": 9912, "name": "newAllowance", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9891, "src": "2221:12:90", "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" } } ], "expression": { "argumentTypes": [ { "typeIdentifier": "t_bytes4", "typeString": "bytes4" }, { "typeIdentifier": "t_address", "typeString": "address" }, { "typeIdentifier": "t_uint256", "typeString": "uint256" } ], "expression": { "argumentTypes": null, "id": 9906, "name": "abi", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": -1, "src": "2165:3:90", "typeDescriptions": { "typeIdentifier": "t_magic_abi", "typeString": "abi" } }, "id": 9907, "isConstant": false, "isLValue": false, "isPure": true, "lValueRequested": false, "memberName": "encodeWithSelector", "nodeType": "MemberAccess", "referencedDeclaration": null, "src": "2165:22:90", "typeDescriptions": { "typeIdentifier": "t_function_abiencodewithselector_pure$_t_bytes4_$returns$_t_bytes_memory_ptr_$", "typeString": "function (bytes4) pure returns (bytes memory)" } }, "id": 9913, "isConstant": false, "isLValue": false, "isPure": false, "kind": "functionCall", "lValueRequested": false, "names": [], "nodeType": "FunctionCall", "src": "2165:69:90", "tryCall": false, "typeDescriptions": { "typeIdentifier": "t_bytes_memory_ptr", "typeString": "bytes memory" } } ], "expression": { "argumentTypes": [ { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" }, { "typeIdentifier": "t_bytes_memory_ptr", "typeString": "bytes memory" } ], "id": 9904, "name": "_callOptionalReturn", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9991, "src": "2138:19:90", "typeDescriptions": { "typeIdentifier": "t_function_internal_nonpayable$_t_contract$_IERC20_$9779_$_t_bytes_memory_ptr_$returns$__$", "typeString": "function (contract IERC20,bytes memory)" } }, "id": 9914, "isConstant": false, "isLValue": false, "isPure": false, "kind": "functionCall", "lValueRequested": false, "names": [], "nodeType": "FunctionCall", "src": "2138:97:90", "tryCall": false, "typeDescriptions": { "typeIdentifier": "t_tuple$__$", "typeString": "tuple()" } }, "id": 9915, "nodeType": "ExpressionStatement", "src": "2138:97:90" } ] }, "documentation": null, "id": 9917, "implemented": true, "kind": "function", "modifiers": [], "name": "safeIncreaseAllowance", "nodeType": "FunctionDefinition", "overrides": null, "parameters": { "id": 9888, "nodeType": "ParameterList", "parameters": [ { "constant": false, "id": 9883, "mutability": "mutable", "name": "token", "nodeType": "VariableDeclaration", "overrides": null, "scope": 9917, "src": "1990:12:90", "stateVariable": false, "storageLocation": "default", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" }, "typeName": { "contractScope": null, "id": 9882, "name": "IERC20", "nodeType": "UserDefinedTypeName", "referencedDeclaration": 9779, "src": "1990:6:90", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" } }, "value": null, "visibility": "internal" }, { "constant": false, "id": 9885, "mutability": "mutable", "name": "spender", "nodeType": "VariableDeclaration", "overrides": null, "scope": 9917, "src": "2004:15:90", "stateVariable": false, "storageLocation": "default", "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" }, "typeName": { "id": 9884, "name": "address", "nodeType": "ElementaryTypeName", "src": "2004:7:90", "stateMutability": "nonpayable", "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" } }, "value": null, "visibility": "internal" }, { "constant": false, "id": 9887, "mutability": "mutable", "name": "value", "nodeType": "VariableDeclaration", "overrides": null, "scope": 9917, "src": "2021:13:90", "stateVariable": false, "storageLocation": "default", "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" }, "typeName": { "id": 9886, "name": "uint256", "nodeType": "ElementaryTypeName", "src": "2021:7:90", "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" } }, "value": null, "visibility": "internal" } ], "src": "1989:46:90" }, "returnParameters": { "id": 9889, "nodeType": "ParameterList", "parameters": [], "src": "2045:0:90" }, "scope": 9992, "src": "1959:283:90", "stateMutability": "nonpayable", "virtual": false, "visibility": "internal" }, { "body": { "id": 9953, "nodeType": "Block", "src": "2334:242:90", "statements": [ { "assignments": [ 9927 ], "declarations": [ { "constant": false, "id": 9927, "mutability": "mutable", "name": "newAllowance", "nodeType": "VariableDeclaration", "overrides": null, "scope": 9953, "src": "2344:20:90", "stateVariable": false, "storageLocation": "default", "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" }, "typeName": { "id": 9926, "name": "uint256", "nodeType": "ElementaryTypeName", "src": "2344:7:90", "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" } }, "value": null, "visibility": "internal" } ], "id": 9940, "initialValue": { "argumentTypes": null, "arguments": [ { "argumentTypes": null, "id": 9937, "name": "value", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9923, "src": "2411:5:90", "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" } }, { "argumentTypes": null, "hexValue": "5361666545524332303a2064656372656173656420616c6c6f77616e63652062656c6f77207a65726f", "id": 9938, "isConstant": false, "isLValue": false, "isPure": true, "kind": "string", "lValueRequested": false, "nodeType": "Literal", "src": "2418:43:90", "subdenomination": null, "typeDescriptions": { "typeIdentifier": "t_stringliteral_2c3af60974a758b7e72e108c9bf0943ecc9e4f2e8af4695da5f52fbf57a63d3a", "typeString": "literal_string \"SafeERC20: decreased allowance below zero\"" }, "value": "SafeERC20: decreased allowance below zero" } ], "expression": { "argumentTypes": [ { "typeIdentifier": "t_uint256", "typeString": "uint256" }, { "typeIdentifier": "t_stringliteral_2c3af60974a758b7e72e108c9bf0943ecc9e4f2e8af4695da5f52fbf57a63d3a", "typeString": "literal_string \"SafeERC20: decreased allowance below zero\"" } ], "expression": { "argumentTypes": null, "arguments": [ { "argumentTypes": null, "arguments": [ { "argumentTypes": null, "id": 9932, "name": "this", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": -28, "src": "2391:4:90", "typeDescriptions": { "typeIdentifier": "t_contract$_SafeERC20_$9992", "typeString": "library SafeERC20" } } ], "expression": { "argumentTypes": [ { "typeIdentifier": "t_contract$_SafeERC20_$9992", "typeString": "library SafeERC20" } ], "id": 9931, "isConstant": false, "isLValue": false, "isPure": true, "lValueRequested": false, "nodeType": "ElementaryTypeNameExpression", "src": "2383:7:90", "typeDescriptions": { "typeIdentifier": "t_type$_t_address_$", "typeString": "type(address)" }, "typeName": { "id": 9930, "name": "address", "nodeType": "ElementaryTypeName", "src": "2383:7:90", "typeDescriptions": { "typeIdentifier": null, "typeString": null } } }, "id": 9933, "isConstant": false, "isLValue": false, "isPure": false, "kind": "typeConversion", "lValueRequested": false, "names": [], "nodeType": "FunctionCall", "src": "2383:13:90", "tryCall": false, "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" } }, { "argumentTypes": null, "id": 9934, "name": "spender", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9921, "src": "2398:7:90", "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" } } ], "expression": { "argumentTypes": [ { "typeIdentifier": "t_address", "typeString": "address" }, { "typeIdentifier": "t_address", "typeString": "address" } ], "expression": { "argumentTypes": null, "id": 9928, "name": "token", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9919, "src": "2367:5:90", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" } }, "id": 9929, "isConstant": false, "isLValue": false, "isPure": false, "lValueRequested": false, "memberName": "allowance", "nodeType": "MemberAccess", "referencedDeclaration": 9738, "src": "2367:15:90", "typeDescriptions": { "typeIdentifier": "t_function_external_view$_t_address_$_t_address_$returns$_t_uint256_$", "typeString": "function (address,address) view external returns (uint256)" } }, "id": 9935, "isConstant": false, "isLValue": false, "isPure": false, "kind": "functionCall", "lValueRequested": false, "names": [], "nodeType": "FunctionCall", "src": "2367:39:90", "tryCall": false, "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" } }, "id": 9936, "isConstant": false, "isLValue": false, "isPure": false, "lValueRequested": false, "memberName": "sub", "nodeType": "MemberAccess", "referencedDeclaration": 2299, "src": "2367:43:90", "typeDescriptions": { "typeIdentifier": "t_function_internal_pure$_t_uint256_$_t_uint256_$_t_string_memory_ptr_$returns$_t_uint256_$bound_to$_t_uint256_$", "typeString": "function (uint256,uint256,string memory) pure returns (uint256)" } }, "id": 9939, "isConstant": false, "isLValue": false, "isPure": false, "kind": "functionCall", "lValueRequested": false, "names": [], "nodeType": "FunctionCall", "src": "2367:95:90", "tryCall": false, "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" } }, "nodeType": "VariableDeclarationStatement", "src": "2344:118:90" }, { "expression": { "argumentTypes": null, "arguments": [ { "argumentTypes": null, "id": 9942, "name": "token", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9919, "src": "2492:5:90", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" } }, { "argumentTypes": null, "arguments": [ { "argumentTypes": null, "expression": { "argumentTypes": null, "expression": { "argumentTypes": null, "id": 9945, "name": "token", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9919, "src": "2522:5:90", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" } }, "id": 9946, "isConstant": false, "isLValue": false, "isPure": false, "lValueRequested": false, "memberName": "approve", "nodeType": "MemberAccess", "referencedDeclaration": 9748, "src": "2522:13:90", "typeDescriptions": { "typeIdentifier": "t_function_external_nonpayable$_t_address_$_t_uint256_$returns$_t_bool_$", "typeString": "function (address,uint256) external returns (bool)" } }, "id": 9947, "isConstant": false, "isLValue": false, "isPure": false, "lValueRequested": false, "memberName": "selector", "nodeType": "MemberAccess", "referencedDeclaration": null, "src": "2522:22:90", "typeDescriptions": { "typeIdentifier": "t_bytes4", "typeString": "bytes4" } }, { "argumentTypes": null, "id": 9948, "name": "spender", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9921, "src": "2546:7:90", "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" } }, { "argumentTypes": null, "id": 9949, "name": "newAllowance", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9927, "src": "2555:12:90", "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" } } ], "expression": { "argumentTypes": [ { "typeIdentifier": "t_bytes4", "typeString": "bytes4" }, { "typeIdentifier": "t_address", "typeString": "address" }, { "typeIdentifier": "t_uint256", "typeString": "uint256" } ], "expression": { "argumentTypes": null, "id": 9943, "name": "abi", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": -1, "src": "2499:3:90", "typeDescriptions": { "typeIdentifier": "t_magic_abi", "typeString": "abi" } }, "id": 9944, "isConstant": false, "isLValue": false, "isPure": true, "lValueRequested": false, "memberName": "encodeWithSelector", "nodeType": "MemberAccess", "referencedDeclaration": null, "src": "2499:22:90", "typeDescriptions": { "typeIdentifier": "t_function_abiencodewithselector_pure$_t_bytes4_$returns$_t_bytes_memory_ptr_$", "typeString": "function (bytes4) pure returns (bytes memory)" } }, "id": 9950, "isConstant": false, "isLValue": false, "isPure": false, "kind": "functionCall", "lValueRequested": false, "names": [], "nodeType": "FunctionCall", "src": "2499:69:90", "tryCall": false, "typeDescriptions": { "typeIdentifier": "t_bytes_memory_ptr", "typeString": "bytes memory" } } ], "expression": { "argumentTypes": [ { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" }, { "typeIdentifier": "t_bytes_memory_ptr", "typeString": "bytes memory" } ], "id": 9941, "name": "_callOptionalReturn", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9991, "src": "2472:19:90", "typeDescriptions": { "typeIdentifier": "t_function_internal_nonpayable$_t_contract$_IERC20_$9779_$_t_bytes_memory_ptr_$returns$__$", "typeString": "function (contract IERC20,bytes memory)" } }, "id": 9951, "isConstant": false, "isLValue": false, "isPure": false, "kind": "functionCall", "lValueRequested": false, "names": [], "nodeType": "FunctionCall", "src": "2472:97:90", "tryCall": false, "typeDescriptions": { "typeIdentifier": "t_tuple$__$", "typeString": "tuple()" } }, "id": 9952, "nodeType": "ExpressionStatement", "src": "2472:97:90" } ] }, "documentation": null, "id": 9954, "implemented": true, "kind": "function", "modifiers": [], "name": "safeDecreaseAllowance", "nodeType": "FunctionDefinition", "overrides": null, "parameters": { "id": 9924, "nodeType": "ParameterList", "parameters": [ { "constant": false, "id": 9919, "mutability": "mutable", "name": "token", "nodeType": "VariableDeclaration", "overrides": null, "scope": 9954, "src": "2279:12:90", "stateVariable": false, "storageLocation": "default", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" }, "typeName": { "contractScope": null, "id": 9918, "name": "IERC20", "nodeType": "UserDefinedTypeName", "referencedDeclaration": 9779, "src": "2279:6:90", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" } }, "value": null, "visibility": "internal" }, { "constant": false, "id": 9921, "mutability": "mutable", "name": "spender", "nodeType": "VariableDeclaration", "overrides": null, "scope": 9954, "src": "2293:15:90", "stateVariable": false, "storageLocation": "default", "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" }, "typeName": { "id": 9920, "name": "address", "nodeType": "ElementaryTypeName", "src": "2293:7:90", "stateMutability": "nonpayable", "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" } }, "value": null, "visibility": "internal" }, { "constant": false, "id": 9923, "mutability": "mutable", "name": "value", "nodeType": "VariableDeclaration", "overrides": null, "scope": 9954, "src": "2310:13:90", "stateVariable": false, "storageLocation": "default", "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" }, "typeName": { "id": 9922, "name": "uint256", "nodeType": "ElementaryTypeName", "src": "2310:7:90", "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" } }, "value": null, "visibility": "internal" } ], "src": "2278:46:90" }, "returnParameters": { "id": 9925, "nodeType": "ParameterList", "parameters": [], "src": "2334:0:90" }, "scope": 9992, "src": "2248:328:90", "stateMutability": "nonpayable", "virtual": false, "visibility": "internal" }, { "body": { "id": 9990, "nodeType": "Block", "src": "3029:681:90", "statements": [ { "assignments": [ 9963 ], "declarations": [ { "constant": false, "id": 9963, "mutability": "mutable", "name": "returndata", "nodeType": "VariableDeclaration", "overrides": null, "scope": 9990, "src": "3378:23:90", "stateVariable": false, "storageLocation": "memory", "typeDescriptions": { "typeIdentifier": "t_bytes_memory_ptr", "typeString": "bytes" }, "typeName": { "id": 9962, "name": "bytes", "nodeType": "ElementaryTypeName", "src": "3378:5:90", "typeDescriptions": { "typeIdentifier": "t_bytes_storage_ptr", "typeString": "bytes" } }, "value": null, "visibility": "internal" } ], "id": 9972, "initialValue": { "argumentTypes": null, "arguments": [ { "argumentTypes": null, "id": 9969, "name": "data", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9959, "src": "3432:4:90", "typeDescriptions": { "typeIdentifier": "t_bytes_memory_ptr", "typeString": "bytes memory" } }, { "argumentTypes": null, "hexValue": "5361666545524332303a206c6f772d6c6576656c2063616c6c206661696c6564", "id": 9970, "isConstant": false, "isLValue": false, "isPure": true, "kind": "string", "lValueRequested": false, "nodeType": "Literal", "src": "3438:34:90", "subdenomination": null, "typeDescriptions": { "typeIdentifier": "t_stringliteral_47fb62c2c272651d2f0f342bac006756b8ba07f21cc5cb87e0fbb9d50c0c585b", "typeString": "literal_string \"SafeERC20: low-level call failed\"" }, "value": "SafeERC20: low-level call failed" } ], "expression": { "argumentTypes": [ { "typeIdentifier": "t_bytes_memory_ptr", "typeString": "bytes memory" }, { "typeIdentifier": "t_stringliteral_47fb62c2c272651d2f0f342bac006756b8ba07f21cc5cb87e0fbb9d50c0c585b", "typeString": "literal_string \"SafeERC20: low-level call failed\"" } ], "expression": { "argumentTypes": null, "arguments": [ { "argumentTypes": null, "id": 9966, "name": "token", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9957, "src": "3412:5:90", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" } } ], "expression": { "argumentTypes": [ { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" } ], "id": 9965, "isConstant": false, "isLValue": false, "isPure": true, "lValueRequested": false, "nodeType": "ElementaryTypeNameExpression", "src": "3404:7:90", "typeDescriptions": { "typeIdentifier": "t_type$_t_address_$", "typeString": "type(address)" }, "typeName": { "id": 9964, "name": "address", "nodeType": "ElementaryTypeName", "src": "3404:7:90", "typeDescriptions": { "typeIdentifier": null, "typeString": null } } }, "id": 9967, "isConstant": false, "isLValue": false, "isPure": false, "kind": "typeConversion", "lValueRequested": false, "names": [], "nodeType": "FunctionCall", "src": "3404:14:90", "tryCall": false, "typeDescriptions": { "typeIdentifier": "t_address", "typeString": "address" } }, "id": 9968, "isConstant": false, "isLValue": false, "isPure": false, "lValueRequested": false, "memberName": "functionCall", "nodeType": "MemberAccess", "referencedDeclaration": 12707, "src": "3404:27:90", "typeDescriptions": { "typeIdentifier": "t_function_internal_nonpayable$_t_address_$_t_bytes_memory_ptr_$_t_string_memory_ptr_$returns$_t_bytes_memory_ptr_$bound_to$_t_address_$", "typeString": "function (address,bytes memory,string memory) returns (bytes memory)" } }, "id": 9971, "isConstant": false, "isLValue": false, "isPure": false, "kind": "functionCall", "lValueRequested": false, "names": [], "nodeType": "FunctionCall", "src": "3404:69:90", "tryCall": false, "typeDescriptions": { "typeIdentifier": "t_bytes_memory_ptr", "typeString": "bytes memory" } }, "nodeType": "VariableDeclarationStatement", "src": "3378:95:90" }, { "condition": { "argumentTypes": null, "commonType": { "typeIdentifier": "t_uint256", "typeString": "uint256" }, "id": 9976, "isConstant": false, "isLValue": false, "isPure": false, "lValueRequested": false, "leftExpression": { "argumentTypes": null, "expression": { "argumentTypes": null, "id": 9973, "name": "returndata", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9963, "src": "3487:10:90", "typeDescriptions": { "typeIdentifier": "t_bytes_memory_ptr", "typeString": "bytes memory" } }, "id": 9974, "isConstant": false, "isLValue": false, "isPure": false, "lValueRequested": false, "memberName": "length", "nodeType": "MemberAccess", "referencedDeclaration": null, "src": "3487:17:90", "typeDescriptions": { "typeIdentifier": "t_uint256", "typeString": "uint256" } }, "nodeType": "BinaryOperation", "operator": ">", "rightExpression": { "argumentTypes": null, "hexValue": "30", "id": 9975, "isConstant": false, "isLValue": false, "isPure": true, "kind": "number", "lValueRequested": false, "nodeType": "Literal", "src": "3507:1:90", "subdenomination": null, "typeDescriptions": { "typeIdentifier": "t_rational_0_by_1", "typeString": "int_const 0" }, "value": "0" }, "src": "3487:21:90", "typeDescriptions": { "typeIdentifier": "t_bool", "typeString": "bool" } }, "falseBody": null, "id": 9989, "nodeType": "IfStatement", "src": "3483:221:90", "trueBody": { "id": 9988, "nodeType": "Block", "src": "3510:194:90", "statements": [ { "expression": { "argumentTypes": null, "arguments": [ { "argumentTypes": null, "arguments": [ { "argumentTypes": null, "id": 9980, "name": "returndata", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": 9963, "src": "3627:10:90", "typeDescriptions": { "typeIdentifier": "t_bytes_memory_ptr", "typeString": "bytes memory" } }, { "argumentTypes": null, "components": [ { "argumentTypes": null, "id": 9982, "isConstant": false, "isLValue": false, "isPure": true, "lValueRequested": false, "nodeType": "ElementaryTypeNameExpression", "src": "3640:4:90", "typeDescriptions": { "typeIdentifier": "t_type$_t_bool_$", "typeString": "type(bool)" }, "typeName": { "id": 9981, "name": "bool", "nodeType": "ElementaryTypeName", "src": "3640:4:90", "typeDescriptions": { "typeIdentifier": null, "typeString": null } } } ], "id": 9983, "isConstant": false, "isInlineArray": false, "isLValue": false, "isPure": true, "lValueRequested": false, "nodeType": "TupleExpression", "src": "3639:6:90", "typeDescriptions": { "typeIdentifier": "t_type$_t_bool_$", "typeString": "type(bool)" } } ], "expression": { "argumentTypes": [ { "typeIdentifier": "t_bytes_memory_ptr", "typeString": "bytes memory" }, { "typeIdentifier": "t_type$_t_bool_$", "typeString": "type(bool)" } ], "expression": { "argumentTypes": null, "id": 9978, "name": "abi", "nodeType": "Identifier", "overloadedDeclarations": [], "referencedDeclaration": -1, "src": "3616:3:90", "typeDescriptions": { "typeIdentifier": "t_magic_abi", "typeString": "abi" } }, "id": 9979, "isConstant": false, "isLValue": false, "isPure": true, "lValueRequested": false, "memberName": "decode", "nodeType": "MemberAccess", "referencedDeclaration": null, "src": "3616:10:90", "typeDescriptions": { "typeIdentifier": "t_function_abidecode_pure$__$returns$__$", "typeString": "function () pure" } }, "id": 9984, "isConstant": false, "isLValue": false, "isPure": false, "kind": "functionCall", "lValueRequested": false, "names": [], "nodeType": "FunctionCall", "src": "3616:30:90", "tryCall": false, "typeDescriptions": { "typeIdentifier": "t_bool", "typeString": "bool" } }, { "argumentTypes": null, "hexValue": "5361666545524332303a204552433230206f7065726174696f6e20646964206e6f742073756363656564", "id": 9985, "isConstant": false, "isLValue": false, "isPure": true, "kind": "string", "lValueRequested": false, "nodeType": "Literal", "src": "3648:44:90", "subdenomination": null, "typeDescriptions": { "typeIdentifier": "t_stringliteral_e11ad79d1e4a7f2e5f376964cb99e8e8f7904e3fc16a109f7a7ecb9aa7956dcd", "typeString": "literal_string \"SafeERC20: ERC20 operation did not succeed\"" }, "value": "SafeERC20: ERC20 operation did not succeed" } ], "expression": { "argumentTypes": [ { "typeIdentifier": "t_bool", "typeString": "bool" }, { "typeIdentifier": "t_stringliteral_e11ad79d1e4a7f2e5f376964cb99e8e8f7904e3fc16a109f7a7ecb9aa7956dcd", "typeString": "literal_string \"SafeERC20: ERC20 operation did not succeed\"" } ], "id": 9977, "name": "require", "nodeType": "Identifier", "overloadedDeclarations": [ -18, -18 ], "referencedDeclaration": -18, "src": "3608:7:90", "typeDescriptions": { "typeIdentifier": "t_function_require_pure$_t_bool_$_t_string_memory_ptr_$returns$__$", "typeString": "function (bool,string memory) pure" } }, "id": 9986, "isConstant": false, "isLValue": false, "isPure": false, "kind": "functionCall", "lValueRequested": false, "names": [], "nodeType": "FunctionCall", "src": "3608:85:90", "tryCall": false, "typeDescriptions": { "typeIdentifier": "t_tuple$__$", "typeString": "tuple()" } }, "id": 9987, "nodeType": "ExpressionStatement", "src": "3608:85:90" } ] } } ] }, "documentation": { "id": 9955, "nodeType": "StructuredDocumentation", "src": "2582:372:90", "text": " @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement\n on the return value: the return value is optional (but if data is returned, it must not be false).\n @param token The token targeted by the call.\n @param data The call data (encoded using abi.encode or one of its variants)." }, "id": 9991, "implemented": true, "kind": "function", "modifiers": [], "name": "_callOptionalReturn", "nodeType": "FunctionDefinition", "overrides": null, "parameters": { "id": 9960, "nodeType": "ParameterList", "parameters": [ { "constant": false, "id": 9957, "mutability": "mutable", "name": "token", "nodeType": "VariableDeclaration", "overrides": null, "scope": 9991, "src": "2988:12:90", "stateVariable": false, "storageLocation": "default", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" }, "typeName": { "contractScope": null, "id": 9956, "name": "IERC20", "nodeType": "UserDefinedTypeName", "referencedDeclaration": 9779, "src": "2988:6:90", "typeDescriptions": { "typeIdentifier": "t_contract$_IERC20_$9779", "typeString": "contract IERC20" } }, "value": null, "visibility": "internal" }, { "constant": false, "id": 9959, "mutability": "mutable", "name": "data", "nodeType": "VariableDeclaration", "overrides": null, "scope": 9991, "src": "3002:17:90", "stateVariable": false, "storageLocation": "memory", "typeDescriptions": { "typeIdentifier": "t_bytes_memory_ptr", "typeString": "bytes" }, "typeName": { "id": 9958, "name": "bytes", "nodeType": "ElementaryTypeName", "src": "3002:5:90", "typeDescriptions": { "typeIdentifier": "t_bytes_storage_ptr", "typeString": "bytes" } }, "value": null, "visibility": "internal" } ], "src": "2987:33:90" }, "returnParameters": { "id": 9961, "nodeType": "ParameterList", "parameters": [], "src": "3029:0:90" }, "scope": 9992, "src": "2959:751:90", "stateMutability": "nonpayable", "virtual": false, "visibility": "private" } ], "scope": 9993, "src": "608:3104:90" } ], "src": "33:3680:90" }, "bytecode": "0x60566023600b82828239805160001a607314601657fe5b30600052607381538281f3fe73000000000000000000000000000000000000000030146080604052600080fdfea2646970667358221220da7d45f5d03c0b37641cfa772f4dc7e5ab3eb0194435f15fdfd097c606ce57b164736f6c63430007000033", "deployedBytecode": "0x73000000000000000000000000000000000000000030146080604052600080fdfea2646970667358221220da7d45f5d03c0b37641cfa772f4dc7e5ab3eb0194435f15fdfd097c606ce57b164736f6c63430007000033", "compiler": { "name": "solc", "version": "0.7.0+commit.9e61f92b.Emscripten.clang", "optimizer": { "enabled": false, "runs": 200 }, "evmVersion": "petersburg" } }