Text formatting in WebIssues

Submitted by mimec on 2013-02-18

Recently I wrote about version 1.1 of WebIssues and my plans to introduce issue descriptions and formatting of comments and descriptions. I also listed various markup languages which I considered for using in WebIssues. But first, let's look at how text is handled in the current version of WebIssues.

WebIssues currently uses plain text for comments. All whitespace characters, including indentation and line breaks, are preserved, making it easy to paste fragments of code directly into comments without breaking their formatting. At the same time, WebIssues wraps long lines, making it possible to write long paragraphs of text which are displayed correctly regardless of the width of the window. This basically corresponds to the "white-space: pre-wrap" CSS style. In addition, external URLs issue identifiers are automatically converted to links.

The key idea behind adding extended formatting options is to preserve compatibility with this "plain text" mode. It should be possible to edit an existing comment, enable formatting and add some markup to the existing text without breaking existing formatting. Now the problem is that most existing markup languages either ignore whitespace (for example HTML, unless wrapped in a <pre> block) or handle it in a specific way (for example, double line breaks are converted to paragraphs, indentation indicates a block of code, etc.). I'm not saying that they are wrong; this often makes sense when copying text from text files or plain text emails. However, I don't want to break habits of existing users of WebIssues. I would like to treat spaces and line breaks identically, whether formatting is enabled or not. Thanks to this, pieces of code will not break, even if they are not marked using special tags. These tags will only be used for decorative purposes, for example, by using different background color and enabling syntax highlighting.

There are generally two kinds of markup used in existing languages: punctuation (brackets, quotes, asterisks, etc.) and tags. Punctuation is used for inline formatting in various flavors of Wiki and languages such as Markdown or Textile, for example to indicate bold or italic text, though there is no single standard. It is also used for block formatting, for example trailing '>' may indicate a quote. HTML tags are commonly used by various languages, in addition to other format specifiers, though they are useful mostly for advanced formatting. Finally, various flavors of BBCode use custom tags, which are similar, but simpler than HTML. I decided to use a combination of punctuation for inline formatting and custom tags for block formatting. It's questionable whether yet another language should be invented when there's so many already, but I think it's going to be intuitive for everyone, and thanks to the embedded markItUp editor, there will be no need to remember it.

The following inline formatting tags will be supported: **bold**, __italic__, `monospace text` and [URL custom links]. The * and _ characters appear commonly in a technical text, so they need to be doubled to avoid false positives. Link syntax is quite similar to Wiki external links, however internal links can be created the same way, for example: [#123 some issue]. In the future it will be possible to introduce real Wiki functionality (where names can will be used instead of numeric identifiers).

Three different block level formatting tags will be suported. A [code][/code] pair will indicate a block of code, with optional syntax highlighing based on Google's prettify. A [quote][/quote] pair will indicate a quote with an optional header. Finally, a [list][/list] pair indicates a bullet list, where each item starts with one or more * (multiple asterisks indicate nested levels). Unlike automatic lists used by many markup languages, explicit tags will make it easy to clearly indicate where the list starts and ends. Also if will be possible to freely mix and nest all three kinds of tags.

I'm now playing with the prototype of the converter, and I may still do some minor changes, but so far I'm rather satisfied with the result. So when version 1.1 is going to be released? By the end of this year - that's all I can promise for now. I will probably release some beta version in a few months. But I still have my book and various other things to do, so don't expect miracles.