Script for managing build and version numbers using git and agvtool. See link in comments below.

version.sh

#!/bin/sh

# Script for managing build and version numbers using git and agvtool.

# Change log:
# v1.0 18-Jul-11 First public release.
# v1.1 29-Sep-12 Launch git, agvtool via xcrun.


version() {
	echo "version.sh 1.1 by Joachim Bondo <osteslag@gmail.com> http://osteslag.tumblr.com"
}

usage() {
	version
cat << EOF >&2

Manages build and version numbers using git and agvtool.

Usage:
  $(basename $0) [options]

Options:
      --terse              Prints the version number in the terse format
  -s, --set                Sets the version number using agvtool
  -p, --plist-path <path>  Write to the built Info.plist file directly
  -b, --bump               Bumps the build number
  -q, --quiet              Supresses output
  -h, --help               Displays this help text
  -v, --version            Displays script version number

Notes:
  - If no options are given, the current versions are printed
  - Specifying -s requires a --plist-path and uses the git tag
EOF
}

list() {
	
	# List current project version and git version. Ignore $should_echo_output.
	# If the --terse option is given, make the output terse.
	
	# Add --abbrev=0 to reduce to latest git tag only (without commit count and SAH):
	git_version=`xcrun git describe --tags`
	build_number=`xcrun agvtool what-version -terse`
	
	if [ $# == 1 ]; then
		echo "${git_version} (${build_number})"
	else
		echo "Version: ${git_version} (${build_number})"
	fi
}

bump() {
	
	# Bumps the build number, i.e. the number in parenthesis.
	
	# Don't print the output of the command itself.
	xcrun agvtool bump -all &> /dev/null
	new_version=`xcrun agvtool what-version -terse`
	if [ $should_echo_output == true ]; then
		echo "Bumped build number to: ${new_version}"
  fi
}

set_version() {
	
	# Set the marketing version of the project. 
	# Take the number from git and apply it to the project.
	# Any "v" prepended to the git tag will be removed.
	
	# Get the current release description from git.
	git_version=`xcrun git describe --tags`
	
	# Check to see if the tag starts with with "v", and remove if so.
	if [[ "${git_version}" == v* ]]; then
		git_version="${git_version#*v}"
	fi
	
	# Set the project version. 
	
	# If we use agvtool for this, and this script runs as a build phase, Xcode
	# insists on reloading the project file which is undesired. But if run from
	# the command line, it makes good sense. If plist_path is not empty, we'll 
	# set the version number in it directly.
	
	if [ -z "$1" ]; then
		xcrun agvtool new-marketing-version "${git_version}" &> /dev/null
		new_version=`xcrun agvtool what-marketing-version -terse1`
	else
		# Remove the (.plist) extension from the path.
		defaults write "${1%.*}" 'CFBundleShortVersionString' "${git_version}" &> /dev/null
		new_version=`defaults read "${1%.*}" 'CFBundleShortVersionString'`
	fi
	
	if [ $should_echo_output == true ]; then
		echo "New version: ${new_version}"
	fi
	
}

# --- Main entry point --------------------------------------------------------

# If we don't have any options, just list versions, or if terse, list terse.
if [ $# == 0 ]; then
	list
	exit 0
elif [ $# == 1 -a $1 == --terse ]; then
	list --terse
	exit 0
fi

# Set default values.
should_set_version_number=false
plist_path=""
should_echo_output=true

# Parse command line options.
while [ $# -gt 0 ]; do
	# Check parameters.
	case $1 in
		-s | --set )
			should_set_version_number=true
			;;
		-p | --plist-path )
			plist_path=$2
			shift;;
		-b | --bump )
			bump
			;;
		-q | --quiet )
			should_echo_output=false
			;;
		-h | --help )
			usage
			exit 1;;
		-v | --version )
			version
			exit 1;;
		* ) # Unknown option
			echo "Error: Unknown option '$1'" 1>&2
			usage
			exit 1;;
	esac	
	shift
done

if [ $should_set_version_number == true ]; then
	if [ ! -e "$plist_path" ]; then
		echo "Error: File does not exist '$plist_path'. Specify a valid --plist-path." 1>&2
		exit 1
	else
		set_version "$plist_path"
	fi
fi

exit 0

Read more in this blogpost.

.... love this script. thanks for the contribution.

@andypeters, my pleasure. Looking forward to seeing where you’ll take it…

Thanks much for your work and contribution in advance.

I having an issue with version 1.0 after upgrading Xcode to Version 4.6.1 (4H512).
The issue is that the build number is not injected to the bundle, even running "version.h -b" command shows right build number.

Any idea?

It's been really useful for me Thanks again.

I resolved the issue by myself.
This issue has nothing to do with Xcode upgrade rather it came from the fact that my Xcode configuration was referring old Info.plist and .pch files.
So, I need to re-config the paths for both Info.plist and .pch files.
Thanks.