dangerfile.js

// Import the feedback functions
import { danger, fail, message, warn } from 'danger';

/**
 * Setup
 */
const { pr } = danger.github;
const { created_files } = danger.git;
const danger_commits = danger.git.commits;

const RELEASE_TRIGGER_REGEX = /^(feat|fix|perf)[:(]/;
const BREAKING_CHANGE_REGEX = /BREAKING CHANGE:/g;

/** No ENV files */
const env_files = created_files.find((file) => file.startsWith('.env'));
if (env_files) {
  fail(
    `🙈 This PR contains \`.env\` files. Please remove files before mergin this PR.`
  );
}

/** No Fixups */
const are_fixups = danger_commits.find((commit) =>
  commit.message.startsWith('fixup!')
);
if (are_fixups) {
  fail('This PR contains unsquashed commits. Please use `--autosquash`.');
}

/* If it's not a branch PR */
if (pr.base.repo.full_name !== pr.head.repo.full_name) {
  warn(
    "🕵️ This PR comes from a fork, and won't get JS generated for QA testing this PR inside the Emission Example app."
  );
}

/** No lock file */
const packageChanged = danger.git.modified_files.includes('package.json');
const lockfileChanged = danger.git.modified_files.includes('yarn.lock');

if (packageChanged && !lockfileChanged) {
  warn(
    `Changes were made to package.json, but not to yarn.lock - <i>'Perhaps you need to run yarn?'</i>`
  );
}

const hasReleaseTriggers = danger.git.commits.reduce(
  (hasReleaseTriggers, commit) =>
    hasReleaseTriggers ||
    RELEASE_TRIGGER_REGEX.test(commit.message) ||
    BREAKING_CHANGE_REGEX.test(commit.message),
  false
);

/** No significatn release */
if (!hasReleaseTriggers) {
  warn(
    'Pull request will not create new release as no significant commit types were found'
  );
}

/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
/* ~ Achievemnts                                                            ~ */
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */

/**
 * Rule: Celebrate PRs that remove more code than they add.
 * Reason: Less is more!
 */
if (danger.github.pr.deletions > danger.github.pr.additions) {
  message(
    `👏 Great job! I see more lines deleted than added. Thanks for keeping us lean!`
  );
}