Out, Damned Tabs

Like many developers I know, I’m a little bit OCD about code formatting. While there are about as many ideas of properly formatted code as there are coders, I think we can all agree that code with tabs and trailing whitespace is not it. Git has the whitespace = fix option, which does a fine job removing trailing spaces before commits, but leaves the spaces in the working copy, and doesn’t manage tabs at all.

I figured there had to be a better way to automate this type of code formatting, and with help from Kevin McFadden’s post, I think I’ve found one, by configuring TextMate to strip off trailing whitespace and replace tabs with spaces whenever a file is saved. Here’s how to set it up:

1. Open the Bundle Editor (Bundles > Bundle Editor > Show Bundle Editor).
2. Create a new bundle using the “+” menu at the bottom of the page. Call it something like “Whitespace.”

3. With your new bundle selected, create a new command called “Save Current File,” and give it the following settings:

   • Save: Current File
   • Command(s): blank
   • Input: None
   • Output: Discard
4. Start recording a new macro (Bundles > Macros > Start Recording).
5. Strip out trailing whitespace (Bundles > Text > Converting/Stripping > Remove Trailing Spaces in Document).
6. Replace tabs with spaces (Text > Convert > Tabs to Spaces).
7. Save the current document (Bundles > Formatting > Save Current Document).
8. Stop recording the macro (Bundles > Macros > Stop Recording).
9. Save the macro (Bundles > Macros > Save Last Recording). Call it something like “Strip Whitespace.”
10. Click in the Activation (Key Equivalent) text field and hit Command+S.

Alternatively, we’ve packaged the bundle up and put it up on GitHub. Instructions for setting it up are on the page, and patches are encouraged.

How About You?

This approach is working well for me; I’m curious if other people are doing anything like this. If you’ve got an alternative way to deal with extraneous whitespace in your code, please tell us how in the comments.