dangerfile.js

import { danger, warn, fail } from 'danger'

const hasAppChanges = danger.git.modified_files.some(file => file.includes('src'))
const hasChangelog = danger.git.modified_files.includes("CHANGELOG.md")
const isDeclaredTrivial = (danger.github.pr.title + danger.github.pr.body).includes('#trivial') || !hasAppChanges

//Make sure we add changelog
if (!hasChangelog && !isDeclaredTrivial) {
  warn("Please add a changelog entry for your changes.");
}

//Mainly to encourage writing up some reasoning about the PR, rather than just leaving a title
if (danger.github.pr.body.length < 3) {
    warn('Please add a detailed summary in the description.') 
}

//Temporary disable this since tasks like create new page may include more than 500 lines of code
// if (git.lines_of_code > 500) {
//     warn('This PR is too big! Consider breaking it down into smaller PRs.') 
// }

//Make it more obvious that a PR is a work in progress and shouldn't be merged yet
if (danger.github.pr.title.includes('[WIP]')) {
    warn('PR is classed as Work in Progress') 
}

//Detect .eslintrc changes and set warnings
if (danger.git.modified_files.includes('.eslintrc')) {
  warn('Changes were made to .eslintrc. Please ensure that you have notified the team to change the existing ESLint rule.')
}

// In the future: make sure non-trivial amounts of code changes come with corresponding tests
/*
const has_test_changes = !git.modified_files.grep(/spec/).empty
if (git.lines_of_code > 50 && has_app_changes && !has_test_changes) {
    warn('There are code changes, but no corresponding tests. ' \
       'Please include tests if this PR introduces any modifications in ' \
       'behavior.',
       sticky: false)
}
*/