HTML Beautifier

A normaliser/beautifier for HTML that also understands embedded Ruby. Ideal for tidying up Rails templates.

What it does

Normalises hard tabs to spaces (or vice versa)
Removes trailing spaces
Indents after opening HTML elements
Outdents before closing elements
Collapses multiple whitespace
Indents after block-opening embedded Ruby (if, do etc.)
Outdents before closing Ruby blocks
Outdents elsif and then indents again
Indents the left-hand margin of JavaScript and CSS blocks to match the indentation level of the code

To update files in-place:

$ htmlbeautifier file1.html.erb [file2.html.erb ...]

or to operate on standard input and output:

$ htmlbeautifier < untidy.html.erb > formatted.html.erb

require 'htmlbeautifier'

beautiful = HtmlBeautifier.beautify(untify_html_string)

You can also specify how to indent (the default is two spaces):

beautiful = HtmlBeautifier.beautify(untidy_html_string, indent: "\t")

This is a Ruby gem. To install the command-line tool (you may need sudo):

$ gem install htmlbeautifier

To use the gem with Bundler, add to your Gemfile:

gem 'htmlbeautifier'

Follow these guidelines when writing commit messages (briefly, the first line should begin with a capital letter, use the imperative mood, be no more than 50 characters, and not end with a period).
Include tests.