gvim failed

#!/bin/bash
set -e -o pipefail

pomfile=pom.xml

# fail if there is no ${pomfile}
if [[ ! -e ${pomfile} ]]; then
  echo "Error: cannot edit ${pomfile}: No such file"
  exit 1
fi

# fail if "git checkout develop" didn't succeed
echo "Calling git checkout develop"
git checkout develop
if [[ $? -ne 0 ]]; then
  exit 1
fi

VERSION=`grep -o -P "(?<=\<version\>).*(?=\</version\>)" ${pomfile} \
       | grep -o -P "[0-9][0-9\.]+[0-9]" | head -n 1`
MINOR=`echo $VERSION | grep -o -P "[0-9]+$"`
MAJOR=`echo $VERSION | grep -o -P "([0-9]+\.)*[0-9]+(?=\.$MINOR)"`
NVERSION=$MAJOR.$(( MINOR+1 ))
echo "Current version ${VERSION} bumped to new version ${NVERSION}"

git flow release start $VERSION
git flow release finish -m $VERSION $VERSION

git checkout develop

# change only the first occasion of pattern
sed "0,/<version>${VERSION}/s//<version>${NVERSION}/" --in-place ${pomfile}

git add pom.xml
git commit -m "version bump"