Cypress MetaMask

Interacting with you MetaMask made "easy". (Depending on how you define "easy" of course...)

This plugin is based on the solutions brought by Jakub Mucha - drptbl in Synpress, and Thomas Ochman in cypress-metamask. The goal of this Fork is to provide a customized version focusing on Tally needs.

Setup

Note: This plugin is in development mode. You might encounter bugs and you will have to tweak your implementation a bit before you get it to work. But it is worth your effort in my opinon. Being able to run automated tests of your application is a good thing. ;-)

Install the package using yarn or npm:

$ yarn add -D @carlos0202/cypress-metamask
// or 
$ npm i -D @carlos0202/cypress-metamask

Import the plugin in cypress/support/index.js

// Import commands.js using ES2015 syntax:
import './commands'
import '@carlos0202/cypress-metamask'

Modify your @carlos0202/cypress/plugins/index.js to include the plugin:

module.exports = (on, config) => {
  require('@carlos0202/cypress-metamask/plugins')(on)
}

Add an .env file to your project root:

These settings are for a Hardhat development environment. You will need to tweak those setting depending on the enviroment you use.

CY_METAMASK_LIB_SECRET_WORDS="test test test test test test test test test test test junk"
PASSWORD=TestMetaMask
CY_METAMASK_LIB_METAMASK_VERSION=latest 
CY_METAMASK_LIB_NETWORK_NAME=localhost 
CY_METAMASK_LIB_RPC_URL=http://127.0.0.1:8545/ 
CY_METAMASK_LIB_CHAIN_ID=1337

Also, you can load a local version of metamask using the following environment variable and value:

CY_METAMASK_LIB_METAMASK_VERSION=local 

This will load a local version already downloaded inside /support/assets/metamask folder inside the library. You can also use a metamask extension locally available in a directory or your choice (inside project root) adding the following environment variable and value:

CY_METAMASK_LIB_METAMASK_LOCAL_PATH=assets/metamask

Add these scripts to your package.json (or modify your existing scripts):

"cy:open": "CYPRESS_REMOTE_DEBUGGING_PORT=9222 cypress open"

You should be ready to go.

Example

There is a small html/javascript (src/index.html) example that requires you to run a local chain to work. It uses the connected wallet to display its address and balance.

Once you have configured your setup and if you spin up a local chain, start a server and run your tests, you should be able to have the test pass.

Step-by-step

1. Start your local chain
2. Start a local web server (yarn start) and navitate to http://localhost:3473
3. Run Cypress (yarn cy:open)

describe('User can load page', () => {
  before(() => {
    cy.setupMetamask();
    cy.changeMetamaskNetwork('localhost')
    cy.visit('/')
  });
  it('is expected to display a sussess message', () => {
    cy.get('[data-cy=title]').should('contain.text', 'MetaMask Detected')
  });
  
  it('is expected to display the local wallet address', () => {
    cy.get('[data-cy=address').should('contain.text', 'Your address is: 0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266')
  });
  
  it('is expected to display the local wallet  balance', () => {
    cy.get('[data-cy=balance').should('contain.text', 'Balance: 10000000000000000000000')
  });
})