Skip to main content

Be Careful Using SASS @extend, CSS3 Selectors, and IE8

I recently ran into a situation where some of my styles were broken in Internet Explorer 8. What makes this different from all the other times my styles broke in IE8 was that, as far as I could tell, it was correct.

Consider the following code: 

  %highlighted {
    background-color: #ff0;
    color: #333;
  }

  .keyword.is-active {
    @extend %highlighted;

    padding: 10px;
    text-transform: uppercase;
  }

No problem, right?

Then why isn't it working? I wasn't sure, until I looked at the compiled CSS and saw something like this: 

  .some-list:nth-child(2n),
  .is-highlighted,
  .keyword.is-active {
    background-color: #ff0;
    color: #333;
  }

  .keyword.is-active {
    padding: 10px;
    text-transform: uppercase;
  }

Since IE8 doesn't support the css selector nth-child, it ignores the entire rule. Without looking at the final output, there's no way of knowing if this will happen ahead of time.

So what can you do? Well, it's probably best (and easiest) to avoid @extend all together and just use mixins. But if you really want to use @extend, then at least be extremely careful and really understand how SASS @extend works.

Labels:

Comments

Post a Comment

Popular posts from this blog

Element.focus() in IE9 running Jasmine tests with Karma

I recently udpated our Jasmine unit tests to run in Karma ; expanding our browser coverage, adding code coverage reports , and using fixtures for testing DOM manipulation . One of my tests kept failing in IE9, but only when I ran from the console. If I attempted to debug in the browser, everything passed. It turns out that IE9 (at least) needed a few ms to catch it's breath before correctly focusing on the starting element. To do this, I just added a 100ms delay before each test ran (Using Jasmine 2.3). beforeEach(function(done){ loadFixtures('myfixture.html'); // Setting focus in IE requires a delay to work correctly! setTimeout(function(){ done(); }, 100); });
Post a Comment
Read more

Flags vs Vendor Prefixes for Experimental CSS

Google recently announced that it will be switching Chrome's rendering engine to a fork of Webkit, called “Blink”. If you're interested, you can read their blog post about Blink . One of the changes we will be seeing in Blink, is the use of browser flags in place of vendor prefixes . What this means, is that rather than prefixing experimental CSS with -webkit-, -moz-, -ms-, -o-, -khtml-, etc.; We will be required to enable these attributes using a flag in the browser (like the ones currently at chrome://flags). If you ask me, both ways have their advantages and disadvantages. Though, in the end, I lean towards the flags over the vendor prefixes, and here's why: #1 Code Bloat On average, using CSS with vendor prefixes requires writing it 5 times . Every time you use it . #2 Future Friendly Eventually, prefixed code will be replaced by the unprefixed code. #3 Browser Dev Friendly Browsers tend to continue to support the prefixed code, even if it doesn...
Post a Comment
Read more

Get width and height of a remote image with VB .NET

The Problem I wanted to grab the width and height of an image that was on a remote server. I've done this with PHP, but never in .NET. The Solution I did a little digging and came across this code (slightly modified for my own purposes). Dim request As HttpWebRequest = DirectCast(WebRequest.Create(URL), HttpWebRequest) request.Method = "GET" request.Accept = "image/*" Dim response As HttpWebResponse = DirectCast(request.GetResponse(), HttpWebResponse) Dim s As Stream = response.GetResponseStream() Dim bmp As New Bitmap(s) Width = bmp.Width Height = bmp.Height
Post a Comment
Read more