Option for disabling "pretty printing" of html part

[AnrichVS]

Some of the mails I send contain user submitted content that was created by Quill editor. Quill editor relies on the white-space: pre-wrap; CSS property to preserve tabs and multiple spaces, see this.

The to_inline_css method(premailer-1.10.3/lib/premailer/adapter/nokogiri.rb:12) causes "pretty printing" of the html that is returned, meaning that newlines are created. Due to white-space: pre-wrap; this causes extra whitespace in the mail. The specific line that causes the "pretty printing" is premailer-1.10.3/lib/premailer/adapter/nokogiri.rb:224. This line does: doc = ::Nokogiri::HTML(thing, nil, @options[:input_encoding] || default_encoding) { |c| c.recover }, NokogiriL::HTML uses DEFAULT_HTML save options, which includes FORMAT. See this.

To overcome this, this can be done:
doc = ::Nokogiri::HTML(thing, nil, @options[:input_encoding] || default_encoding, Nokogiri::XML::Node::SaveOptions::DEFAULT_HTML ^ Nokogiri::XML::Node::SaveOptions::FORMAT) { |c| c.recover }

Preferably that would be a option, which can then be passed through via @options.

I plan on making a pull request for this soon, creating this issue to ensure that I'm not missing something. I've perused all the current options, and it doesn't seem like there's any other way to overcome this. I guess one can create an interceptor that strips new lines before sending the mail, but it feels like a dirty workaround.

[akzhan]

You should create specs on all of supported adapters (:nokogiri, :nokogiri_fast, :nokogumbo).

[AnrichVS]

Unfortunately I haven't had time to work on this, but I will create specs for all those adaptors once I do complete implementation.

Note to self: the Nokogiri save options should not be passed at ::Nokogiri::HTML() but rather to the .to_html() method, as in:
@processed_doc.to_html(:encoding => @options[:output_encoding], save_with: @options[:nokogiri_html_options])

[akzhan]

It's simple as

[:nokogiri, :nokogiri_fast, :nokogumbo].each do |adapter|
  # instantiate
end

Specs like that are common.