Update release script

Author: martinthomson

release.sh

@@ -7,17 +7,29 @@ cd "$root"
 sub='{ s/^.*["'"'"']\([0-9]*\.[0-9]*\.[0-9]*\)["'"'"'].*$/\1/;p; }'
 old1=$(sed -n -e '/version *=/'"$sub"'' python/setup.py)
 old2=$(sed -n -e '/"version" *:/'"$sub"'' nodejs/package.json)
-
-if [ "$old1" != "$old2" ]; then
+if [[ "$old1" != "$old2" ]]; then
     echo "Versions aren't the same: $old1 != $old2" 1>&2
     exit 1
 fi
-IFS=. v=($old1)
-new="${v[0]}.${v[1]}.$((${v[2]} + 1))"
 
-sub='s/\(["'"'"']\)'"$old1"'["'"'"']/\1'"$new"'\1/'
-sed -i~ -e '/version *=/'"$sub" python/setup.py
-sed -i~ -e '/"version" *:/'"$sub" nodejs/package.json
+case "$1" in
+    +)
+        IFS=. v=($old1)
+        new="${v[0]}.${v[1]}.$((${v[2]} + 1))"
+
+        sub='s/\(["'"'"']\)'"$old1"'["'"'"']/\1'"$new"'\1/'
+        sed -i~ -e '/version *=/'"$sub" python/setup.py
+        sed -i~ -e '/"version" *:/'"$sub" nodejs/package.json
+        ;;
+
+    =)
+        new="$old1"
+        ;;
+    *)
+        echo "Publish current version: $0 =" 1>&2
+        echo "Increment version and publish: $0 +" 1>&2
+        exit 2
+esac
 
 pushd "$root"/python
 python setup.py sdist
@@ -28,6 +40,8 @@ pushd "$root"/nodejs
 npm publish
 popd
 
-git commit -m "Update version to $new" python/setup.py nodejs/package.json
+if [[ "$1" == "+" ]]; then
+    git commit -m "Update version to $new" python/setup.py nodejs/package.json
+fi
 git tag -a v"$new" -m "Release version $new"
 git push origin v"$new"