Teach github-pages how to release

README.md

@@ -18,9 +18,9 @@ Alternatively, you can add the following to your project's Gemfile:
 
 To update to the latest version of Jekyll and associated dependencies, simply run `gem update github-pages`, or if you've installed via Bundler, `bundle update github-pages`.
 
-## Building
+## Releasing
 
-To build a new version of the gem, run `script/build`
+To release a new version of this gem, run `script/release` from the `master` branch.
 
 ## License
 

script/release

@@ -0,0 +1,38 @@
+#!/bin/sh
+# Tag and push a release.
+
+set -e
+
+# Make sure we're in the project root.
+
+cd $(dirname "$0")/..
+
+# Build a new gem archive.
+
+rm -rf github-pages-*.gem
+gem build -q github-pages.gemspec
+
+# Make sure we're on the master branch.
+
+(git branch | grep -q '* master') || {
+  echo "Only release from the master branch."
+  exit 1
+}
+
+# Figure out what version we're releasing.
+
+tag=v`ls github-pages-*.gem | sed 's/^github-pages-\(.*\)\.gem$/\1/'`
+
+# Make sure we haven't released this version before.
+
+git fetch -t origin
+
+(git tag -l | grep -q "$tag") && {
+  echo "Whoops, there's already a '${tag}' tag."
+  exit 1
+}
+
+# Tag it and bag it.
+
+gem push github-pages-*.gem && git tag "$tag" &&
+  git push origin master && git push origin "$tag"