fix parser error on '…\n…' template expression

[kamikat]

Change to accept template strings like:

pug`\n  div\n    p test\n`

Which is identical to

pug`
  div
    p test
`

[codecov-io]

Codecov Report

Merging #80 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master      #80   +/-   ##
=======================================
  Coverage   82.24%   82.24%           
=======================================
  Files          20       20           
  Lines         445      445           
  Branches      103      103           
=======================================
  Hits          366      366           
  Misses         70       70           
  Partials        9        9

Impacted Files	Coverage Δ
src/index.js	100% <100%> (ø)	⬆️

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[ezhlobo]

@kamikat hello! Could you please give more context why is it useful? Is there a reason to write new lines by hands instead of using indentation as it's how pugjs works?

[kamikat]

Given following tagged template string in CoffeeScript:

pug"""
  div
    p test
"""

which compiles to:

pug`div\n  p test`;

[ezhlobo]

@kamikat hey, something inside me really afraid of having this in the codebase. I don't have rational reason against it though.

While I'm so cautious and in the middle of thinking process, are you able to fork and use your fork as a dependency in your project? I don't want my delay be a blocker for you.

[kamikat]

I've been used my own fork for a while.

And yes, this is a quick hack to solve the problem with coffee compiler without enough robustness.

I'll open another feature request for this.

[ForbesLindesay]

These two strings are not identical. This is intentional:

pug`
  pre= 'Hello\nWorld'
`;

Is not the same as:

pug`
  pre= 'Hello
World'
`;

The first is valid pug code, the later is not. I realise this sucks for CoffeeScript users, but I don't think that should be a priority for us here.

[audunolsen]

I believe having whitespace sensitive syntax throughout the whole codebase, at least coherently throughout a single react cjsx file has great appeal. Hoping this isn't dismissed entirely.

[audunolsen]

I've done some quick research and discovered that the there's active work in the CoffeeScript repo to separate explicit and implicit newlines in template literals it outputs. The discussion spawned from someone having an issue pretty identical to this one, only a different template literal tag.

A workaround as of today is to use the CoffeeScript "ast" branch, I've tested it myself and pug tagged strings compile flawlessly. Put the following in your package.json:
"coffeescript": "jashkenas/coffeescript#ast"