Cher's Tips and Tricks

Simple Code Reformatting

The Vim editor has some really nice features. For reformatting code, we will use the following features:

• Supplying multiple files on the command line, using a list of source files generated by something else (e.g. the find command)
• A simple but very powerful command language
• Giving startup commands with -c
• A global regular expression substitution using %s
• Writing a file using w
• Quitting vim after the job is done using q
• Configuring the tab width using set tabstop=4
• Configuring vim to use spaces instead of tabs using set expandtab
• Retabbing files using retab
• Looping over all files executing a sequence of commands using bufdo

Simple code reformatting can be useful in various places:

• When importing, migrating or fixing code that has tabs while it should have spaces instead. That's especially the case when importing code from broken IDEs like Eclipse or Visual Studio.
• When removing trailing whitespace from source code.

ex -s -c "set et ts=4 | bufdo! retab | w" -c "q" $(find client server -name "*.c" -or -name "*.h")

ex -s -c 'bufdo! %s/\s\+$//e | w' -c "q" $(find client server -name "*.c" -or -name "*.h")

ex -s -c 'set et ts=4 | bufdo! retab | %s/\s\+$//e | w' -c "q" $(find client server -name "*.c" -or -name "*.h")

Using kdiff3 as 3-way-merge-tool for subversion

Create the following shell script. Put it somewhere in the system. I've stored it at /home/cher/bin/kdiff3.sh.

#!/bin/bash
kdiff3 ${10} ${9} ${11} -o ${10}.merged
cat ${10}.merged
rm ${10}.merged

Now change ~/.subversion/config to include the following line in the section [helpers]:

diff3-cmd = /home/cher/bin/kdiff3.sh