More robust implementation of readBreakpoints()

[megatronCGN]

At least in Firefox 53, the body:after content is updated with the JSON data once a matching media is found in CSS. However, when the viewport is resized and does no longer match any of the defined breakpoints, the .content reverts to 'none', a literal string value. This fails during JSON parsing, effectively leaving the breakpoint unchanged.

I also had the same issue with IE 11. I did not examine any closer there, but that also disappeared with this change.

[mpdude]

Although the symptoms are similar to #10, the cause is different.

In FF 53, the breakpoints = false statement is never reached.

[eduardoboucas]

First of all, thanks for this! If I understand correctly, JSON.parse() is failing in certain situations causing the script to break. If that's the case, shouldn't we deal with that in the catch block, instead of returning inside the try?

[mpdude]

We'd then have...

function readBreakpoints() {
    if (window.getComputedStyle && (window.getComputedStyle(element, '::after').content !== '')) {
      var data = window.getComputedStyle(element, '::after').content;

      try {
        breakpoints = JSON.parse(removeQuotes(data));
      } catch (err) {
        breakpoints = false;      
      }
    } else { 
      breakpoints = false;
    }
  }

@eduardoboucas if you prefer that, I'll ask @megatronCGN to change it

[eduardoboucas]

That would be great, thanks!

[megatronCGN]

@eduardoboucas done, you're welcome

[eduardoboucas]

Tiny detail, could you remove the trailing whitespace here?

[eduardoboucas]

Merged, thank you! I'll release to npm now.

[eduardoboucas]

Done, 1.0.3 released. @mpdude could you confirm whether this also closes #11?

[mpdude]

Will do, head over to #11.