Acid2 in IE8

It’s cool that Microsoft has announced that IE8 passes the Acid2 test (in “IE8 Standards Mode” – I sure hope that mode is enabled by default.

But what I found interesting is how they announced it: By showing the check-in mail that signified the committing of the code that implemented the fix into the main IE source tree. Check that out here.

A few things it reveals:

  • This fix touches a lot of files. This wasn’t a simple fix.
  • Microsoft uses Perforce for source code management. This is indicated by the //depot/path syntax used for the files.
  • IE8 work is happening on a branch, called LONGHORN_IE8. Typically new features are added to the “main branch” (which usually doesn’t have a name). I wonder what’s on the main branch.
  • Obviously some IE work started before source file names could be more than 8 characters long. LSTXBR1.H?
  • Microsoft uses some sort of pre-checkin code review process. This is a good sign; we use this at on my team at Adobe and I think it’s proven itself valuable.
  • No C# code in sight; IE’s core is still all unmanaged C++ code.
  • The IE devs use a mix of extensions for C++ source and header files; cxx vs cpp, .h vs .hxx. Personally I’ve never worked on a project that used cxx and hxx, so they seem unnatural to me.

Nothing earth shattering, but an interesting peek behind the scenes nonetheless.