Add updateSubmodule.sh script

Generates a commit that updates the VE core submodule to
master (or a specified version)

Change-Id: I54c5fa18e9f9d7bb65a490415c5c139fd6072925

bin/updateSubmodule.sh

@@ -0,0 +1,68 @@
+#!/usr/bin/env bash
+
+# This script generates a commit that updates the lib/ve submodule
+# ./bin/updateSubmodule.sh        updates to master
+# ./bin/updateSubmodule.sh hash   updates to specified hash
+
+# cd to the VisualEditor directory
+cd $(cd $(dirname $0)/..; pwd)
+
+# Check that both working directories are clean
+if git status -uno --ignore-submodules | grep -i changes > /dev/null
+then
+	echo >&2 "Working directory must be clean"
+	exit 1
+fi
+cd lib/ve
+if git status -uno --ignore-submodules | grep -i changes > /dev/null
+then
+	echo >&2 "lib/ve working directory must be clean"
+	exit 1
+fi
+cd ../..
+
+git fetch origin
+# Create sync-repos branch if needed and reset it to master
+git checkout -B sync-repos origin/master
+git submodule update
+cd lib/ve
+git fetch origin
+
+# Figure out what to set the submodule to
+if [ "x$1" != "x" ]
+then
+	TARGET="$1"
+	TARGETDESC="$1"
+else
+	TARGET=origin/master
+	TARGETDESC="master ($(git rev-parse --short origin/master))"
+fi
+
+# Generate commit summary
+# TODO recurse
+NEWCHANGES=$(git log ..$TARGET --oneline --no-merges --reverse --color=never)
+NEWCHANGESDISPLAY=$(git log ..$TARGET --oneline --no-merges --reverse --color=always)
+COMMITMSG=$(cat <<END
+Update VE core submodule to $TARGETDESC
+
+New changes:
+$NEWCHANGES
+END
+)
+# Check out master of VE core
+git checkout $TARGET
+
+# Commit
+cd ../..
+git commit lib/ve -m "$COMMITMSG" > /dev/null
+if [ "$?" == "1" ]
+then
+	echo >&2 "No changes"
+else
+	cat >&2 <<END
+
+
+Created commit with changes:
+$NEWCHANGESDISPLAY
+END
+fi