TestnetERC20

An implementation of ERC20 with the same interface as the Compound project’s testnet tokens (mainly DAI)

This contract can be deployed or the interface can be used to communicate with Compound’s ERC20 tokens. Note: this token should never be used to store real value since it allows permissionless minting.

constructor(string _name, string _symbol, uint8 _decimals) public

allocateTo(address _owner, uint256 value) external

Mints value tokens to the owner address.

totalSupply() → uint256 public

See {IERC20-totalSupply}.

balanceOf(address account) → uint256 public

See {IERC20-balanceOf}.

transfer(address recipient, uint256 amount) → bool public

See {IERC20-transfer}.

Requirements:

  • recipient cannot be the zero address.

  • the caller must have a balance of at least amount.

allowance(address owner, address spender) → uint256 public

See {IERC20-allowance}.

approve(address spender, uint256 amount) → bool public

See {IERC20-approve}.

Requirements:

  • spender cannot be the zero address.

transferFrom(address sender, address recipient, uint256 amount) → bool public

See {IERC20-transferFrom}.

Emits an {Approval} event indicating the updated allowance. This is not required by the EIP. See the note at the beginning of {ERC20};

Requirements: - sender and recipient cannot be the zero address. - sender must have a balance of at least amount. - the caller must have allowance for sender’s tokens of at least `amount.

increaseAllowance(address spender, uint256 addedValue) → bool public

Atomically increases the allowance granted to spender by the caller.

This is an alternative to {approve} that can be used as a mitigation for problems described in {IERC20-approve}.

Emits an {Approval} event indicating the updated allowance.

Requirements:

  • spender cannot be the zero address.

decreaseAllowance(address spender, uint256 subtractedValue) → bool public

Atomically decreases the allowance granted to spender by the caller.

This is an alternative to {approve} that can be used as a mitigation for problems described in {IERC20-approve}.

Emits an {Approval} event indicating the updated allowance.

Requirements:

  • spender cannot be the zero address.

  • spender must have allowance for the caller of at least subtractedValue.

_transfer(address sender, address recipient, uint256 amount) internal

Moves tokens amount from sender to recipient.

This is internal function is equivalent to {transfer}, and can be used to e.g. implement automatic token fees, slashing mechanisms, etc.

Emits a {Transfer} event.

Requirements:

  • sender cannot be the zero address.

  • recipient cannot be the zero address.

  • sender must have a balance of at least amount.

_mint(address account, uint256 amount) internal

Creates amount tokens and assigns them to account, increasing the total supply.

Emits a {Transfer} event with from set to the zero address.

Requirements

  • to cannot be the zero address.

_burn(address account, uint256 amount) internal

Destroys amount tokens from account, reducing the total supply.

Emits a {Transfer} event with to set to the zero address.

Requirements

  • account cannot be the zero address.

  • account must have at least amount tokens.

_approve(address owner, address spender, uint256 amount) internal

Sets amount as the allowance of spender over the `owner`s tokens.

This is internal function is equivalent to approve, and can be used to e.g. set automatic allowances for certain subsystems, etc.

Emits an {Approval} event.

Requirements:

  • owner cannot be the zero address.

  • spender cannot be the zero address.

_burnFrom(address account, uint256 amount) internal

Destroys amount tokens from account.amount is then deducted from the caller’s allowance.

See {_burn} and {_approve}.

_beforeTokenTransfer(address from, address to, uint256 amount) internal

Hook that is called before any transfer of tokens. This includes minting and burning.

Calling conditions:

  • when from and to are both non-zero, amount of from’s tokens will be to transferred to `to.

  • when from is zero, amount tokens will be minted for to.

  • when to is zero, amount of `from’s tokens will be burned.

  • from and to are never both zero.

To learn more about hooks, head to Using Hooks.

_msgSender() → address payable internal

_msgData() → bytes internal

Transfer(address from, address to, uint256 value) event

Emitted when value tokens are moved from one account (from) to another (to).

Note that value may be zero.

Approval(address owner, address spender, uint256 value) event

Emitted when the allowance of a spender for an owner is set by a call to {approve}. value is the new allowance.

© UMA Project 2018-2019