Automatic versioning in Android using Ant and Git

custom_rules.xml

<?xml version="1.0" encoding="UTF-8"?>
<project name="application-custom">
    
	<macrodef name="git" taskname="@{taskname}">
	    <attribute name="command" />
	    <attribute name="dir" default="" />
	    <attribute name="property" default="" />
	    <attribute name="taskname" default="" />
	    <attribute name="failonerror" default="on" />
	    <element name="args" optional="true" />
	    <sequential>
	        <exec executable="git" dir="@{dir}" outputproperty="@{property}" 
	        	failifexecutionfails="@{failonerror}" failonerror="@{failonerror}">
	            <arg value="@{command}" />
	            <args/>
	        </exec>
	    </sequential>
	</macrodef>
	
    <target name="-pre-build">
    	<git command="rev-list" property="versioning.code" taskname="versioning">
    		<args>
	    		<arg value="master" />
	    		<arg value="--first-parent" />
    			<arg value="--count" />
			</args>
		</git>
    	<git command="describe" property="versioning.name" taskname="versioning">
    		<args>
	    		<arg value="--tags" />
	    		<arg value="--dirty" />
    			<arg value="--abbrev=7" />
			</args>
		</git>
        <echo level="info" taskname="versioning">${versioning.code}, ${versioning.name}</echo>
    	<replaceregexp file="AndroidManifest.xml" match='android:versionCode=".*"' replace='android:versionCode="${versioning.code}"' />
    	<replaceregexp file="AndroidManifest.xml" match='android:versionName=".*"' replace='android:versionName="${versioning.name}"' />
    </target>
	
    <target name="-post-build" >
    	<replaceregexp file="AndroidManifest.xml" match='android:versionCode=".*"' replace='android:versionCode="0"' />
    	<replaceregexp file="AndroidManifest.xml" match='android:versionName=".*"' replace='android:versionName="0"' />
    </target>
	
</project>