Prettyhtml / Prettyhtml

Opinionated general formatter for your Angular, Vue, Svelte or pure HTML5 templates. Try it on the playground.

Project status: Unfortunately, This project lacks maintainers. Prettier has landed HTML support in 1.15.0. I recommend it to use it if it matches your requirements. If you want to contribute to this project, feel free to create a PR/Issue.

Features

• Indentation based primary on node-level + tag length, not content.
• Can parse Angular, Vue or HTML5 templates.
• Formats embedded content with prettier with respect to your local settings.
• Doesn't change the behaviour of your attributes and tags.
• Remove all superfluous white-space. There are two additional rules:
  • Collapses multiple blank lines into a single blank line.
  • Empty lines at the start and end of blocks are removed. (Files always end with a single newline, though.)
• Enforce consistent output of your HTML.
• Follows the same option philosophy as prettier.

Framework specific features

Packages

• prettyhtml CLI and API.
• prettyhtml-formatter Formatter.
• prettyhtml-hast-to-html Stringifier.
• prettyhtml-hastscript Hyperscript compatible DSL for creating virtual HAST trees.
• prettyhtml-sort-attributes Sort attributes alphabetically.
• prettyhtml-quick Formats your changed files based on Git.
• webparser Optimized HTML parser for formatters
• expression-parser Framework agnostic template expression parser.
• rehype-webparser Adapter between HTML parser and rehype.
• rehype-minify-whitespace Collapse whitespace.
• hast-util-from-parse Transform webparser AST to HAST.

Ignore element

Adding this flag before a tag will preserve from whitespace and/or attribute wrapping.

1. Preserve from indentation, whitespace and attribute wrapping

<!--prettyhtml-ignore-->
<div></div>

2. Preserve only from whitespace processing. This excludes indentation.

<!--prettyhtml-preserve-whitespace-->
<h1> foo </h1>

3. Preserve only from attribute wrapping

<!--prettyhtml-preserve-attribute-wrapping-->
<h1 foo="bar" ...> foo </h1>

Install

# regular
$ npm install @starptech/prettyhtml --global

# when using proxy like sinopia/verdaccio
$ npm install @starptech/prettyhtml --global --registry=https://registry.npmjs.org/

CLI

This will process recursively all HTML files in the current directory.

$ prettyhtml example.html "./**/*.html"

Help

$ prettyhtml --help

Pre-Commit hook integration

We provide a simple package called prettyhtml-quick which is able to format only changed files. This example use husky to manage git hooks in the package.json

{
  "husky": {
    "hooks": {
      "precommit": "prettyhtml-quick --staged"
    }
  }
}

API

prettyhtml(doc: string, options?): vFile

Formats a string and returns a vFile. The method can throw e.g when a parsing error was produced. The error is from type vfile-message.

options

options.tabWidth

The space width of your indentation level (default: 2)

options.useTabs

Use tabs instead spaces for indentation (default: false)

options.printWidth

Use different maximum line length (default: 80)

options.usePrettier

Use prettier for embedded content (default: true)

options.prettier

Use custom prettier settings for embedded content (default: local config)

options.singleQuote

Use single quote instead double quotes (default: false)

options.wrapAttributes

Force to wrap attributes (when it has multiple, default: false)

options.sortAttributes

Sort attributes alphabetically (default: false)

Editor support

• VSCode extension (not published yet)
• Vetur Vue tooling for VS Code

Why

Prettier has landed HTML support some days ago. This is awesome and will help many people to reduce the headache of correct formatting in teams. The reason why I still using prettyhtml is clear:

• It is very easy to maintain because we have a specification and an ecosystem (and @vfile, @syntax-tree) of plugins.
• It should be able to format any superset of HTML as long it is parseable with minor tweaks. We use a modified version of the Angular 6 template parser. There is no need to maintain multiple parser.
• Prettyhtml doesn't try to understand all Javascript frameworks in depth even when it means that the user has to update some places manually.

Acknowledgement

Big thanks to the creators of the excellent rehype and unified ecosystem.