zoo: update token contract

4 files changed, 455 insertions, 14 deletions

diff --git a/cmd/zoo/monkey/Token.sol b/cmd/zoo/monkey/Token.sol
new file mode 100644
index 000000000..08625a32c
--- /dev/null
+++ b/cmd/zoo/monkey/Token.sol
@@ -0,0 +1,434 @@
+
+// File: openzeppelin-solidity/contracts/token/ERC20/IERC20.sol
+
+pragma solidity ^0.5.0;
+
+/**
+ * @dev Interface of the ERC20 standard as defined in the EIP. Does not include
+ * the optional functions; to access them see `ERC20Detailed`.
+ */
+interface IERC20 {
+    /**
+     * @dev Returns the amount of tokens in existence.
+     */
+    function totalSupply() external view returns (uint256);
+
+    /**
+     * @dev Returns the amount of tokens owned by `account`.
+     */
+    function balanceOf(address account) external view returns (uint256);
+
+    /**
+     * @dev Moves `amount` tokens from the caller's account to `recipient`.
+     *
+     * Returns a boolean value indicating whether the operation succeeded.
+     *
+     * Emits a `Transfer` event.
+     */
+    function transfer(address recipient, uint256 amount) external returns (bool);
+
+    /**
+     * @dev Returns the remaining number of tokens that `spender` will be
+     * allowed to spend on behalf of `owner` through `transferFrom`. This is
+     * zero by default.
+     *
+     * This value changes when `approve` or `transferFrom` are called.
+     */
+    function allowance(address owner, address spender) external view returns (uint256);
+
+    /**
+     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
+     *
+     * Returns a boolean value indicating whether the operation succeeded.
+     *
+     * > Beware that changing an allowance with this method brings the risk
+     * that someone may use both the old and the new allowance by unfortunate
+     * transaction ordering. One possible solution to mitigate this race
+     * condition is to first reduce the spender's allowance to 0 and set the
+     * desired value afterwards:
+     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
+     *
+     * Emits an `Approval` event.
+     */
+    function approve(address spender, uint256 amount) external returns (bool);
+
+    /**
+     * @dev Moves `amount` tokens from `sender` to `recipient` using the
+     * allowance mechanism. `amount` is then deducted from the caller's
+     * allowance.
+     *
+     * Returns a boolean value indicating whether the operation succeeded.
+     *
+     * Emits a `Transfer` event.
+     */
+    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
+
+    /**
+     * @dev Emitted when `value` tokens are moved from one account (`from`) to
+     * another (`to`).
+     *
+     * Note that `value` may be zero.
+     */
+    event Transfer(address indexed from, address indexed to, uint256 value);
+
+    /**
+     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
+     * a call to `approve`. `value` is the new allowance.
+     */
+    event Approval(address indexed owner, address indexed spender, uint256 value);
+}
+
+// File: openzeppelin-solidity/contracts/math/SafeMath.sol
+
+pragma solidity ^0.5.0;
+
+/**
+ * @dev Wrappers over Solidity's arithmetic operations with added overflow
+ * checks.
+ *
+ * Arithmetic operations in Solidity wrap on overflow. This can easily result
+ * in bugs, because programmers usually assume that an overflow raises an
+ * error, which is the standard behavior in high level programming languages.
+ * `SafeMath` restores this intuition by reverting the transaction when an
+ * operation overflows.
+ *
+ * Using this library instead of the unchecked operations eliminates an entire
+ * class of bugs, so it's recommended to use it always.
+ */
+library SafeMath {
+    /**
+     * @dev Returns the addition of two unsigned integers, reverting on
+     * overflow.
+     *
+     * Counterpart to Solidity's `+` operator.
+     *
+     * Requirements:
+     * - Addition cannot overflow.
+     */
+    function add(uint256 a, uint256 b) internal pure returns (uint256) {
+        uint256 c = a + b;
+        require(c >= a, "SafeMath: addition overflow");
+
+        return c;
+    }
+
+    /**
+     * @dev Returns the subtraction of two unsigned integers, reverting on
+     * overflow (when the result is negative).
+     *
+     * Counterpart to Solidity's `-` operator.
+     *
+     * Requirements:
+     * - Subtraction cannot overflow.
+     */
+    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
+        require(b <= a, "SafeMath: subtraction overflow");
+        uint256 c = a - b;
+
+        return c;
+    }
+
+    /**
+     * @dev Returns the multiplication of two unsigned integers, reverting on
+     * overflow.
+     *
+     * Counterpart to Solidity's `*` operator.
+     *
+     * Requirements:
+     * - Multiplication cannot overflow.
+     */
+    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
+        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
+        // benefit is lost if 'b' is also tested.
+        // See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
+        if (a == 0) {
+            return 0;
+        }
+
+        uint256 c = a * b;
+        require(c / a == b, "SafeMath: multiplication overflow");
+
+        return c;
+    }
+
+    /**
+     * @dev Returns the integer division of two unsigned integers. Reverts on
+     * division by zero. The result is rounded towards zero.
+     *
+     * Counterpart to Solidity's `/` operator. Note: this function uses a
+     * `revert` opcode (which leaves remaining gas untouched) while Solidity
+     * uses an invalid opcode to revert (consuming all remaining gas).
+     *
+     * Requirements:
+     * - The divisor cannot be zero.
+     */
+    function div(uint256 a, uint256 b) internal pure returns (uint256) {
+        // Solidity only automatically asserts when dividing by 0
+        require(b > 0, "SafeMath: division by zero");
+        uint256 c = a / b;
+        // assert(a == b * c + a % b); // There is no case in which this doesn't hold
+
+        return c;
+    }
+
+    /**
+     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
+     * Reverts when dividing by zero.
+     *
+     * Counterpart to Solidity's `%` operator. This function uses a `revert`
+     * opcode (which leaves remaining gas untouched) while Solidity uses an
+     * invalid opcode to revert (consuming all remaining gas).
+     *
+     * Requirements:
+     * - The divisor cannot be zero.
+     */
+    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
+        require(b != 0, "SafeMath: modulo by zero");
+        return a % b;
+    }
+}
+
+// File: openzeppelin-solidity/contracts/token/ERC20/ERC20.sol
+
+pragma solidity ^0.5.0;
+
+
+
+/**
+ * @dev Implementation of the `IERC20` interface.
+ *
+ * This implementation is agnostic to the way tokens are created. This means
+ * that a supply mechanism has to be added in a derived contract using `_mint`.
+ * For a generic mechanism see `ERC20Mintable`.
+ *
+ * *For a detailed writeup see our guide [How to implement supply
+ * mechanisms](https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226).*
+ *
+ * We have followed general OpenZeppelin guidelines: functions revert instead
+ * of returning `false` on failure. This behavior is nonetheless conventional
+ * and does not conflict with the expectations of ERC20 applications.
+ *
+ * Additionally, an `Approval` event is emitted on calls to `transferFrom`.
+ * This allows applications to reconstruct the allowance for all accounts just
+ * by listening to said events. Other implementations of the EIP may not emit
+ * these events, as it isn't required by the specification.
+ *
+ * Finally, the non-standard `decreaseAllowance` and `increaseAllowance`
+ * functions have been added to mitigate the well-known issues around setting
+ * allowances. See `IERC20.approve`.
+ */
+contract ERC20 is IERC20 {
+    using SafeMath for uint256;
+
+    mapping (address => uint256) private _balances;
+
+    mapping (address => mapping (address => uint256)) private _allowances;
+
+    uint256 private _totalSupply;
+
+    /**
+     * @dev See `IERC20.totalSupply`.
+     */
+    function totalSupply() public view returns (uint256) {
+        return _totalSupply;
+    }
+
+    /**
+     * @dev See `IERC20.balanceOf`.
+     */
+    function balanceOf(address account) public view returns (uint256) {
+        return _balances[account];
+    }
+
+    /**
+     * @dev See `IERC20.transfer`.
+     *
+     * Requirements:
+     *
+     * - `recipient` cannot be the zero address.
+     * - the caller must have a balance of at least `amount`.
+     */
+    function transfer(address recipient, uint256 amount) public returns (bool) {
+        _transfer(msg.sender, recipient, amount);
+        return true;
+    }
+
+    /**
+     * @dev See `IERC20.allowance`.
+     */
+    function allowance(address owner, address spender) public view returns (uint256) {
+        return _allowances[owner][spender];
+    }
+
+    /**
+     * @dev See `IERC20.approve`.
+     *
+     * Requirements:
+     *
+     * - `spender` cannot be the zero address.
+     */
+    function approve(address spender, uint256 value) public returns (bool) {
+        _approve(msg.sender, spender, value);
+        return true;
+    }
+
+    /**
+     * @dev 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 `value`.
+     * - the caller must have allowance for `sender`'s tokens of at least
+     * `amount`.
+     */
+    function transferFrom(address sender, address recipient, uint256 amount) public returns (bool) {
+        _transfer(sender, recipient, amount);
+        _approve(sender, msg.sender, _allowances[sender][msg.sender].sub(amount));
+        return true;
+    }
+
+    /**
+     * @dev 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.
+     */
+    function increaseAllowance(address spender, uint256 addedValue) public returns (bool) {
+        _approve(msg.sender, spender, _allowances[msg.sender][spender].add(addedValue));
+        return true;
+    }
+
+    /**
+     * @dev 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`.
+     */
+    function decreaseAllowance(address spender, uint256 subtractedValue) public returns (bool) {
+        _approve(msg.sender, spender, _allowances[msg.sender][spender].sub(subtractedValue));
+        return true;
+    }
+
+    /**
+     * @dev 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`.
+     */
+    function _transfer(address sender, address recipient, uint256 amount) internal {
+        require(sender != address(0), "ERC20: transfer from the zero address");
+        require(recipient != address(0), "ERC20: transfer to the zero address");
+
+        _balances[sender] = _balances[sender].sub(amount);
+        _balances[recipient] = _balances[recipient].add(amount);
+        emit Transfer(sender, recipient, amount);
+    }
+
+    /** @dev 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.
+     */
+    function _mint(address account, uint256 amount) internal {
+        require(account != address(0), "ERC20: mint to the zero address");
+
+        _totalSupply = _totalSupply.add(amount);
+        _balances[account] = _balances[account].add(amount);
+        emit Transfer(address(0), account, amount);
+    }
+
+     /**
+     * @dev Destoys `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.
+     */
+    function _burn(address account, uint256 value) internal {
+        require(account != address(0), "ERC20: burn from the zero address");
+
+        _totalSupply = _totalSupply.sub(value);
+        _balances[account] = _balances[account].sub(value);
+        emit Transfer(account, address(0), value);
+    }
+
+    /**
+     * @dev 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.
+     */
+    function _approve(address owner, address spender, uint256 value) internal {
+        require(owner != address(0), "ERC20: approve from the zero address");
+        require(spender != address(0), "ERC20: approve to the zero address");
+
+        _allowances[owner][spender] = value;
+        emit Approval(owner, spender, value);
+    }
+
+    /**
+     * @dev Destoys `amount` tokens from `account`.`amount` is then deducted
+     * from the caller's allowance.
+     *
+     * See `_burn` and `_approve`.
+     */
+    function _burnFrom(address account, uint256 amount) internal {
+        _burn(account, amount);
+        _approve(account, msg.sender, _allowances[account][msg.sender].sub(amount));
+    }
+}
+
+// File: contracts/TWD.sol
+
+pragma solidity ^0.5.0;
+
+
+contract TestERC20Token is ERC20 {
+    string  public constant name = "New Taiwan Dollar";
+    string  public constant symbol = "NTD";
+    uint8   public constant decimals = 2;
+
+    constructor() public {
+        _mint(msg.sender, 1000000000000000 ether);
+    }
+}
diff --git a/cmd/zoo/monkey/banana.go b/cmd/zoo/monkey/banana.go
deleted file mode 100644
index 7ecb53fc9..000000000
--- a/cmd/zoo/monkey/banana.go
+++ /dev/null
@@ -1,4 +0,0 @@
-package monkey
-
-var bananaContract = "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"
-var bananaABIJSON = "[{\"constant\":true,\"inputs\":[],\"name\":\"name\",\"outputs\":[{\"name\":\"\",\"type\":\"string\"}],\"payable\":false,\"stateMutability\":\"view\",\"type\":\"function\"},{\"constant\":false,\"inputs\":[{\"name\":\"_spender\",\"type\":\"address\"},{\"name\":\"_value\",\"type\":\"uint256\"}],\"name\":\"approve\",\"outputs\":[{\"name\":\"\",\"type\":\"bool\"}],\"payable\":false,\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"constant\":true,\"inputs\":[],\"name\":\"totalSupply\",\"outputs\":[{\"name\":\"\",\"type\":\"uint256\"}],\"payable\":false,\"stateMutability\":\"view\",\"type\":\"function\"},{\"constant\":false,\"inputs\":[{\"name\":\"_from\",\"type\":\"address\"},{\"name\":\"_to\",\"type\":\"address\"},{\"name\":\"_value\",\"type\":\"uint256\"}],\"name\":\"transferFrom\",\"outputs\":[{\"name\":\"\",\"type\":\"bool\"}],\"payable\":false,\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"constant\":true,\"inputs\":[],\"name\":\"decimals\",\"outputs\":[{\"name\":\"\",\"type\":\"uint8\"}],\"payable\":false,\"stateMutability\":\"view\",\"type\":\"function\"},{\"constant\":false,\"inputs\":[{\"name\":\"_spender\",\"type\":\"address\"},{\"name\":\"_subtractedValue\",\"type\":\"uint256\"}],\"name\":\"decreaseApproval\",\"outputs\":[{\"name\":\"\",\"type\":\"bool\"}],\"payable\":false,\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"constant\":true,\"inputs\":[{\"name\":\"_owner\",\"type\":\"address\"}],\"name\":\"balanceOf\",\"outputs\":[{\"name\":\"\",\"type\":\"uint256\"}],\"payable\":false,\"stateMutability\":\"view\",\"type\":\"function\"},{\"constant\":true,\"inputs\":[],\"name\":\"owner\",\"outputs\":[{\"name\":\"\",\"type\":\"address\"}],\"payable\":false,\"stateMutability\":\"view\",\"type\":\"function\"},{\"constant\":true,\"inputs\":[],\"name\":\"symbol\",\"outputs\":[{\"name\":\"\",\"type\":\"string\"}],\"payable\":false,\"stateMutability\":\"view\",\"type\":\"function\"},{\"constant\":false,\"inputs\":[{\"name\":\"_to\",\"type\":\"address\"},{\"name\":\"_value\",\"type\":\"uint256\"}],\"name\":\"transfer\",\"outputs\":[{\"name\":\"\",\"type\":\"bool\"}],\"payable\":false,\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"constant\":false,\"inputs\":[{\"name\":\"_spender\",\"type\":\"address\"},{\"name\":\"_addedValue\",\"type\":\"uint256\"}],\"name\":\"increaseApproval\",\"outputs\":[{\"name\":\"\",\"type\":\"bool\"}],\"payable\":false,\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"constant\":true,\"inputs\":[{\"name\":\"_owner\",\"type\":\"address\"},{\"name\":\"_spender\",\"type\":\"address\"}],\"name\":\"allowance\",\"outputs\":[{\"name\":\"\",\"type\":\"uint256\"}],\"payable\":false,\"stateMutability\":\"view\",\"type\":\"function\"},{\"constant\":false,\"inputs\":[{\"name\":\"newOwner\",\"type\":\"address\"}],\"name\":\"transferOwnership\",\"outputs\":[],\"payable\":false,\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"inputs\":[],\"payable\":false,\"stateMutability\":\"nonpayable\",\"type\":\"constructor\"},{\"anonymous\":false,\"inputs\":[{\"indexed\":true,\"name\":\"previousOwner\",\"type\":\"address\"},{\"indexed\":true,\"name\":\"newOwner\",\"type\":\"address\"}],\"name\":\"OwnershipTransferred\",\"type\":\"event\"},{\"anonymous\":false,\"inputs\":[{\"indexed\":true,\"name\":\"owner\",\"type\":\"address\"},{\"indexed\":true,\"name\":\"spender\",\"type\":\"address\"},{\"indexed\":false,\"name\":\"value\",\"type\":\"uint256\"}],\"name\":\"Approval\",\"type\":\"event\"},{\"anonymous\":false,\"inputs\":[{\"indexed\":true,\"name\":\"from\",\"type\":\"address\"},{\"indexed\":true,\"name\":\"to\",\"type\":\"address\"},{\"indexed\":false,\"name\":\"value\",\"type\":\"uint256\"}],\"name\":\"Transfer\",\"type\":\"event\"}]"
diff --git a/cmd/zoo/monkey/feeder.go b/cmd/zoo/monkey/feeder.go
index 095cb90ab..8aa20fb61 100644
--- a/cmd/zoo/monkey/feeder.go
+++ b/cmd/zoo/monkey/feeder.go
@@ -32,18 +32,18 @@ import (
 	"github.com/tangerine-network/go-tangerine/crypto"
 )
 
-var bananaABI abi.ABI
+var tokenABI abi.ABI
 
 func init() {
 	var err error
-	bananaABI, err = abi.JSON(strings.NewReader(bananaABIJSON))
+	tokenABI, err = abi.JSON(strings.NewReader(TestERC20TokenABI))
 	if err != nil {
 		panic(err)
 	}
 }
 
-func (m *Monkey) DistributeBanana(contract common.Address) {
-	fmt.Println("Distributing Banana to random accounts ...")
+func (m *Monkey) DistributeToken(contract common.Address) {
+	fmt.Println("Distributing Token to random accounts ...")
 	address := crypto.PubkeyToAddress(m.source.PublicKey)
 	nonce, err := m.PendingNonceAt(context.Background(), address)
 	if err != nil {
@@ -51,11 +51,10 @@ func (m *Monkey) DistributeBanana(contract common.Address) {
 	}
 
 	ctxs := make([]*client.TransferContext, len(m.keys))
-	amount := new(big.Int)
-	amount.SetString("10000000000000000", 10)
+	amount := new(big.Int).Mul(big.NewInt(1e7), big.NewInt(1e2))
 	for i, key := range m.keys {
 		address := crypto.PubkeyToAddress(key.PublicKey)
-		input, err := bananaABI.Pack("transfer", address, amount)
+		input, err := tokenABI.Pack("transfer", address, amount)
 		if err != nil {
 			panic(err)
 		}
@@ -74,9 +73,10 @@ func (m *Monkey) DistributeBanana(contract common.Address) {
 
 func (m *Monkey) Feed() uint64 {
 	fmt.Println("Deploying contract ...")
-	contract := m.Deploy(m.source, bananaContract, nil, new(big.Int), math.MaxUint64)
+	contract := m.Deploy(
+		m.source, TestERC20TokenBin, nil, new(big.Int), math.MaxUint64)
 	fmt.Println("  Contract deployed: ", contract.String())
-	m.DistributeBanana(contract)
+	m.DistributeToken(contract)
 
 	time.Sleep(5 * time.Second)
 
@@ -87,7 +87,8 @@ loop:
 		ctxs := make([]*client.TransferContext, len(m.keys))
 		for i, key := range m.keys {
 			to := crypto.PubkeyToAddress(m.keys[rand.Int()%len(m.keys)].PublicKey)
-			input, err := bananaABI.Pack("transfer", to, big.NewInt(rand.Int63n(100)+1))
+			input, err := tokenABI.Pack("transfer", to,
+				new(big.Int).Mul(big.NewInt(rand.Int63n(1000)), big.NewInt(1e2)))
 			if err != nil {
 				panic(err)
 			}
diff --git a/cmd/zoo/monkey/token.go b/cmd/zoo/monkey/token.go
new file mode 100644
index 000000000..b2c626f2f
--- /dev/null
+++ b/cmd/zoo/monkey/token.go
@@ -0,0 +1,10 @@
+// Code generated - DO NOT EDIT.
+// This file is a generated binding and any manual changes will be lost.
+
+package monkey
+
+// TestERC20TokenABI is the input ABI used to generate the binding from.
+const TestERC20TokenABI = "[{\"constant\":true,\"inputs\":[],\"name\":\"name\",\"outputs\":[{\"name\":\"\",\"type\":\"string\"}],\"payable\":false,\"stateMutability\":\"view\",\"type\":\"function\"},{\"constant\":false,\"inputs\":[{\"name\":\"spender\",\"type\":\"address\"},{\"name\":\"value\",\"type\":\"uint256\"}],\"name\":\"approve\",\"outputs\":[{\"name\":\"\",\"type\":\"bool\"}],\"payable\":false,\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"constant\":true,\"inputs\":[],\"name\":\"totalSupply\",\"outputs\":[{\"name\":\"\",\"type\":\"uint256\"}],\"payable\":false,\"stateMutability\":\"view\",\"type\":\"function\"},{\"constant\":false,\"inputs\":[{\"name\":\"sender\",\"type\":\"address\"},{\"name\":\"recipient\",\"type\":\"address\"},{\"name\":\"amount\",\"type\":\"uint256\"}],\"name\":\"transferFrom\",\"outputs\":[{\"name\":\"\",\"type\":\"bool\"}],\"payable\":false,\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"constant\":true,\"inputs\":[],\"name\":\"decimals\",\"outputs\":[{\"name\":\"\",\"type\":\"uint8\"}],\"payable\":false,\"stateMutability\":\"view\",\"type\":\"function\"},{\"constant\":false,\"inputs\":[{\"name\":\"spender\",\"type\":\"address\"},{\"name\":\"addedValue\",\"type\":\"uint256\"}],\"name\":\"increaseAllowance\",\"outputs\":[{\"name\":\"\",\"type\":\"bool\"}],\"payable\":false,\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"constant\":true,\"inputs\":[{\"name\":\"account\",\"type\":\"address\"}],\"name\":\"balanceOf\",\"outputs\":[{\"name\":\"\",\"type\":\"uint256\"}],\"payable\":false,\"stateMutability\":\"view\",\"type\":\"function\"},{\"constant\":true,\"inputs\":[],\"name\":\"symbol\",\"outputs\":[{\"name\":\"\",\"type\":\"string\"}],\"payable\":false,\"stateMutability\":\"view\",\"type\":\"function\"},{\"constant\":false,\"inputs\":[{\"name\":\"spender\",\"type\":\"address\"},{\"name\":\"subtractedValue\",\"type\":\"uint256\"}],\"name\":\"decreaseAllowance\",\"outputs\":[{\"name\":\"\",\"type\":\"bool\"}],\"payable\":false,\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"constant\":false,\"inputs\":[{\"name\":\"recipient\",\"type\":\"address\"},{\"name\":\"amount\",\"type\":\"uint256\"}],\"name\":\"transfer\",\"outputs\":[{\"name\":\"\",\"type\":\"bool\"}],\"payable\":false,\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"constant\":true,\"inputs\":[{\"name\":\"owner\",\"type\":\"address\"},{\"name\":\"spender\",\"type\":\"address\"}],\"name\":\"allowance\",\"outputs\":[{\"name\":\"\",\"type\":\"uint256\"}],\"payable\":false,\"stateMutability\":\"view\",\"type\":\"function\"},{\"inputs\":[],\"payable\":false,\"stateMutability\":\"nonpayable\",\"type\":\"constructor\"},{\"anonymous\":false,\"inputs\":[{\"indexed\":true,\"name\":\"from\",\"type\":\"address\"},{\"indexed\":true,\"name\":\"to\",\"type\":\"address\"},{\"indexed\":false,\"name\":\"value\",\"type\":\"uint256\"}],\"name\":\"Transfer\",\"type\":\"event\"},{\"anonymous\":false,\"inputs\":[{\"indexed\":true,\"name\":\"owner\",\"type\":\"address\"},{\"indexed\":true,\"name\":\"spender\",\"type\":\"address\"},{\"indexed\":false,\"name\":\"value\",\"type\":\"uint256\"}],\"name\":\"Approval\",\"type\":\"event\"}]"
+
+// TestERC20TokenBin is the compiled bytecode used for deploying new contracts.
+const TestERC20TokenBin = `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