humpty/src/printUnmentionedChanges.js

Makes sure your changelogs mention your breaking changes

// @flow

import * as changeTypes from "./changeTypes";

function condensedGitRef(gitRef) {
  const isSha = gitRef.match(/^[0-9a-f]{6,}$/);
  if (isSha) {
    return gitRef.slice(0, 6);
  }
  return gitRef;
}

export default function printUnmentionedChanges({
  unmentionedChanges,
  unmentionedChangeCount,
  oldApi,
  newApi
}) {
  if (unmentionedChangeCount === 0) {
    return;
  }

  const plural = unmentionedChangeCount === 1 ? "" : "s";
  const intro = `🚨 Found ${unmentionedChangeCount} breaking API change${plural} not mentioned in git commits (${condensedGitRef(
    oldApi
  )}..${condensedGitRef(newApi)}):`;
  const fullChanges = unmentionedChanges
    .map(changedExport => {
      const exportName = changedExport.isDefaultExport
        ? "Default export"
        : changedExport.name;

      const changeList = changedExport.apiChanges
        .map(apiChange => {
          switch (apiChange.changeType) {
            case changeTypes.PROP_TYPE_CHANGED:
              return `  - ${apiChange.changeType}: "${apiChange.propName}" was ${apiChange.oldType}, now ${apiChange.newType}.`;
            case changeTypes.PROP_REMOVED:
              return `  - ${apiChange.changeType}: "${apiChange.propName}".`;
            case changeTypes.PROP_MADE_REQUIRED:
              return `  - ${apiChange.changeType}: "${apiChange.propName}" was optional, now required.`;
            case changeTypes.PROP_MADE_OPTIONAL:
              return `  - ${apiChange.changeType}: "${apiChange.propName}" was required, now optional.`;
            case !changedExport.isDefaultExport && changeTypes.EXPORT_REMOVED:
              return `  - ${apiChange.changeType}: ${changedExport.name} is no longer exported from the entry file.`;
            case changedExport.isDefaultExport && changeTypes.EXPORT_REMOVED:
              return `  - ${apiChange.changeType}: There is no longer a default export.`;
            default:
              break;
          }
        })
        .join("\n");

      return `${exportName}\n${changeList}`;
    })
    .join("\n");
  return `${intro}\n\n${fullChanges}`;
}