lerna version - how to avoid commits?

Question

Lerna is overall quite a powerfull tool for managing monorepoes in JavaScript with a lot of nice features.

However one thing that I really struggle to find recently - is an ability to gain more controll on the changes lerna applies, specifically when running lerna version command.

lerna version generates CHANGELOG.md changes based on commits, bumps up packages versions and creates a new commit (or with certain flags updates the current commit).

I would like to find a way to prevent changes from being commited to customize my CHANGELOG.md based on what lerna has generated - Is there a way to do so?

I'm using [email protected]

Answer 1

Lerna is using external dependencies to do the conventional changelog stuff, for example the bump is created by the conventional-changelog-recommend-bump dependency and the changelog, you could guess, is produced by using the conventional-changelog dependency.

You can customize how the changelog is created by defining a changelogPreset with the conventionalcommits name and passing and defining a types object in Lerna and in that object you can provide an array of type rules to follow which follows the spec defined in conventional-changelog-config-spec

For example you can see below a config with emojis and different conventional titles

Note that the example shown below was copied from this public repo, which is not mine, and they use Lerna-Lite which uses the same config as Lerna, you can also take a look at their changelog.md to see what it produces

{
  "$schema": "node_modules/@lerna-lite/cli/schemas/lerna-schema.json",
  "version": "0.0.1"
  "packages": [
    "packages/*"
  ],
  "changelogPreset": {
    "name": "conventionalcommits",
    "types": [
      {
        "type": "feat",
        "section": "✨ Features"
      },
      {
        "type": "fix",
        "section": " Bug Fixes"
      },
      {
        "type": "chore",
        "section": " Chore",
        "hidden": true
      },
      {
        "type": "docs",
        "section": " Documentation"
      },
      {
        "type": "style",
        "section": " Styles"
      },
      {
        "type": "refactor",
        "section": "♻️ Code Refactoring"
      },
      {
        "type": "perf",
        "section": "⚡ Performance Improvements"
      },
      {
        "type": "test",
        "section": "✅ Tests",
        "hidden": true
      },
      {
        "type": "revert",
        "section": "⏪ Revert",
        "hidden": true
      },
      {
        "type": "build",
        "section": "‍ Build System"
      },
      {
        "type": "ci",
        "section": " Continuous Integration"
      }
    ],
    "issuePrefixes": [
      "#"
    ],
    "issueUrlFormat": "{{host}}/{{owner}}/{{repository}}/issues/{{id}}",
    "commitUrlFormat": "{{host}}/{{owner}}/{{repository}}/commit/{{hash}}",
    "compareUrlFormat": "{{host}}/{{owner}}/{{repository}}/compare/{{previousTag}}...{{currentTag}}",
    "userUrlFormat": "{{host}}/{{user}}"
  }
}

You can see some of that have been tagged as hidden which mean that they won't show up in the changelog.

Also note that in lerna.json, you could also add a ignoreChanges array of files to ignore so that it doesn't bump for irrelevant files like spec files or fixtures, for example in Lerna-Lite we use this config

{ 
  "$schema": "node_modules/@lerna-lite/cli/schemas/lerna-schema.json",
  "version": "0.0.1"
  "ignoreChanges": [
    "**/__fixtures__/**",
    "**/__tests__/**",
    "**/helpers/**",
    "**/*.md"
  ]
}