a precommit hook for naive build versioning in R package development

precommit.sh

#!/bin/bash

D=`date +%Y%m%d%H%M%S`
branch=`git status|grep -ie 'on branch master'`

if [ -z "$branch" ]; then
  cat DESCRIPTION | sed -e 's/^\(Version: [0-9]*\.[0-9]*\).*/\1.'$D'/' > DESCRIPTION.temp
  rm DESCRIPTION
  mv DESCRIPTION.temp DESCRIPTION
  git add DESCRIPTION
fi

So basically, we're appending the datetime stamp (down to the second) to the version number in the DESCRIPTION file.

Why check whether the branch is master or not? Because in our original workflow all development was done on the dev branch, and we only merged to master for releases. We didn't want releases to have burdensome version numbers, so we exclude the extended version number when on the master branch.