Class: ERC20::FakeWallet

Inherits:
Object
  • Object
show all
Includes:
Checks
Defined in:
lib/erc20/fake_wallet.rb

Overview

A fake wallet that behaves like a ERC20::Wallet.

It rejects exactly what the real wallet rejects, so that a broken private key, address, or amount fails in a test the same way it would fail with a real provider, where money is at stake.

Author

Yegor Bugayenko (yegor256@gmail.com)

Copyright

Copyright (c) 2025 Yegor Bugayenko

License

MIT

Constant Summary collapse

TXN_HASH = 
'0x172de9cda30537eae68ab4a96163ebbb8f8a85293b8737dd2e5deb4714b14623'

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ FakeWallet

Ctor.



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# File 'lib/erc20/fake_wallet.rb', line 27

def initialize
  @host = 'example.com'
  @port = 443
  @ssl = true
  @chain = 1
  @contract = ERC20::Wallet::USDT
  @ws_path = '/'
  @http_path = '/'
  @history = []
  @balances = {}
  @eth_balances = {}
end

Instance Attribute Details

#chain ⇒ Object (readonly)

Returns the value of attribute chain.



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# File 'lib/erc20/fake_wallet.rb', line 24

def chain
  @chain
end

#contract ⇒ Object (readonly)

Returns the value of attribute contract.



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# File 'lib/erc20/fake_wallet.rb', line 24

def contract
  @contract
end

#history ⇒ Object (readonly)

Returns the value of attribute history.



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# File 'lib/erc20/fake_wallet.rb', line 24

def history
  @history
end

#host ⇒ Object (readonly)

Returns the value of attribute host.



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# File 'lib/erc20/fake_wallet.rb', line 24

def host
  @host
end

#http_path ⇒ Object (readonly)

Returns the value of attribute http_path.



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# File 'lib/erc20/fake_wallet.rb', line 24

def http_path
  @http_path
end

#port ⇒ Object (readonly)

Returns the value of attribute port.



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# File 'lib/erc20/fake_wallet.rb', line 24

def port
  @port
end

#ssl ⇒ Object (readonly)

Returns the value of attribute ssl.



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# File 'lib/erc20/fake_wallet.rb', line 24

def ssl
  @ssl
end

#ws_path ⇒ Object (readonly)

Returns the value of attribute ws_path.



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# File 'lib/erc20/fake_wallet.rb', line 24

def ws_path
  @ws_path
end

Instance Method Details

#accept(addresses, active = [], raw: false, delay: 1, subscription_id: rand(1..99_999)) ⇒ Object

Wait and accept.

Parameters:

  • addresses (Array<String>) —

    Addresses to monitor

  • active (Array) (defaults to: []) —

    List of addresses that we are actually listening to

  • raw (Boolean) (defaults to: false) —

    TRUE if you need to get JSON events as they arrive from Websockets

  • delay (Numeric) (defaults to: 1) —

    How many seconds to wait between eth_subscribe calls

  • subscription_id (Integer) (defaults to: rand(1..99_999)) —

    Unique ID of the subscription



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# File 'lib/erc20/fake_wallet.rb', line 160

def accept(addresses, active = [], raw: false, delay: 1, subscription_id: rand(1..99_999))
  to_addresses(addresses)
  to_active(active)
  to_delay(delay)
  to_subscription(subscription_id)
  @history << { method: :accept, addresses:, active:, raw:, delay:, subscription_id: }
  addresses.to_a.each { |a| active.append(a) }
  loop do
    sleep(delay)
    to_addresses(addresses)
    a = addresses.to_a.sample
    next if a.nil?
    yield(
      if raw
        {}
      else
        {
          amount: 424_242,
          block: 42,
          from: '0xd5ff1bfcde7a03da61ad229d962c74f1ea2f16a5',
          index: 0,
          to: a,
          txn: TXN_HASH
        }
      end
    )
  end
end

#balance(address) ⇒ Integer

Get ERC20 balance of a public address.

Parameters:

  • address (String) —

    Public key, in hex, starting from '0x'

Returns:

  • (Integer) —

    Balance, in tokens



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# File 'lib/erc20/fake_wallet.rb', line 58

def balance(address)
  to_address(address)
  b = @balances[address] || 42_000_000
  @history << { method: :balance, address:, result: b }
  b
end

#eth_balance(address) ⇒ Integer

Get ETH balance of a public address.

Parameters:

  • address (String) —

    Public key, in hex, starting from '0x'

Returns:

  • (Integer) —

    Balance, in tokens



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# File 'lib/erc20/fake_wallet.rb', line 69

def eth_balance(address)
  to_address(address)
  b = @eth_balances[address] || 77_000_000_000_000_000
  @history << { method: :eth_balance, address:, result: b }
  b
end

#eth_pay(priv, address, amount, price: gas_price) ⇒ String

Send a single ETH payment from a private address to a public one.

Parameters:

  • priv (String) —

    Private key, in hex

  • address (String) —

    Public key, in hex

  • amount (Integer) —

    The amount of ETHs to send

  • price (Integer) (defaults to: gas_price) —

    The most you pay per computation unit, in wei

Returns:

  • (String) —

    Transaction hash



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# File 'lib/erc20/fake_wallet.rb', line 143

def eth_pay(priv, address, amount, price: gas_price)
  to_priv(priv)
  to_address(address)
  to_amount(amount)
  to_price(price)
  hex = TXN_HASH
  @history << { method: :eth_pay, priv:, address:, amount:, price:, result: hex }
  hex
end

#gas_estimate(from, to, amount) ⇒ Integer

How many gas units are required to send an ERC20 transaction.

Parameters:

  • from (String) —

    The departing address, in hex

  • to (String) —

    Arriving address, in hex

  • amount (Integer) —

    How many ERC20 tokens to send

Returns:

  • (Integer) —

    How many gas units required



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# File 'lib/erc20/fake_wallet.rb', line 95

def gas_estimate(from, to, amount)
  to_address(from)
  to_address(to)
  to_amount(amount)
  gas = 66_000
  @history << { method: :gas_estimate, from:, to:, amount:, result: gas }
  gas
end

#gas_price ⇒ Integer

What is the price of gas unit in wei?

The unit is the same as in ERC20::Wallet#gas_price: a price in gwei would be a billion times smaller and would make every fee computed in a test look affordable, while in production it wouldn't be.

Returns:

  • (Integer) —

    Price of gas unit, in wei (1 gwei = 0.000000001 ETH)



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# File 'lib/erc20/fake_wallet.rb', line 111

def gas_price
  wei = 55_555_000_000
  @history << { method: :gas_price, result: wei }
  wei
end

#pay(priv, address, amount, limit: nil, price: gas_price) ⇒ String

Send a single ERC20 payment from a private address to a public one.

Parameters:

  • priv (String) —

    Private key, in hex

  • address (String) —

    Public key, in hex

  • amount (Integer) —

    The amount of ERC20 tokens to send

  • limit (Integer) (defaults to: nil) —

    Optional gas limit

  • price (Integer) (defaults to: gas_price) —

    The most you pay per computation unit, in wei

Returns:

  • (String) —

    Transaction hash



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# File 'lib/erc20/fake_wallet.rb', line 125

def pay(priv, address, amount, limit: nil, price: gas_price)
  to_priv(priv)
  to_address(address)
  to_amount(amount)
  to_limit(limit) if limit
  to_price(price)
  hex = TXN_HASH
  @history << { method: :pay, priv:, address:, amount:, limit:, price:, result: hex }
  hex
end

#set_balance(address, tokens) ⇒ Object

Set balance, to be returned by the balance().

Parameters:

  • address (String) —

    Public key, in hex, starting from '0x'

  • tokens (Integer) —

    How many tokens to put there



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# File 'lib/erc20/fake_wallet.rb', line 43

def set_balance(address, tokens)
  @balances[address] = tokens
end

#set_eth_balance(address, wei) ⇒ Object

Set balance, to be returned by the balance().

Parameters:

  • address (String) —

    Public key, in hex, starting from '0x'

  • wei (Integer) —

    How many wei to put there



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# File 'lib/erc20/fake_wallet.rb', line 50

def set_eth_balance(address, wei)
  @eth_balances[address] = wei
end

#sum_of(txn, to: nil) ⇒ Integer

Get ERC20 amount (in tokens) that was sent in the given transaction.

Parameters:

  • txn (String) —

    Hex of transaction

  • to (String) (defaults to: nil) —

    Public key of the receiver, in hex, starting from '0x'

Returns:

  • (Integer) —

    Amount, in ERC20 tokens



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# File 'lib/erc20/fake_wallet.rb', line 81

def sum_of(txn, to: nil)
  to_txn(txn)
  to_address(to) unless to.nil?
  tokens = 42_000_000
  @history << { method: :sum_of, txn:, to:, result: tokens }
  tokens
end