Add release script

Author: mjackson

package.json

@@ -10,6 +10,7 @@
     "build-umd": "webpack modules/index.js umd/react-broadcast.js",
     "build-min": "webpack -p modules/index.js umd/react-broadcast.min.js",
     "prepublish": "node ./scripts/build.js",
+    "release": "node ./scripts/release.js",
     "test": "npm run lint",
     "lint": "eslint modules"
   },
@@ -35,6 +36,7 @@
     "gzip-size": "^3.0.0",
     "in-publish": "^2.0.0",
     "pretty-bytes": "^4.0.2",
+    "readline-sync": "^1.4.4",
     "webpack": "^1.13.2"
   }
 }

scripts/release.js

@@ -0,0 +1,48 @@
+const resolvePath = require('path').resolve
+const readFileSync = require('fs').readFileSync
+const execSync = require('child_process').execSync
+const prompt = require('readline-sync').question
+
+const exec = (command) =>
+  execSync(command, { stdio: 'inherit' })
+
+const getPackageVersion = () =>
+  JSON.parse(readFileSync(resolvePath(__dirname, '../package.json'))).version
+
+if (process.cwd() !== resolvePath(__dirname, '..')) {
+  console.error('The release script must be run from the repo root')
+  process.exit(1)
+}
+
+// Get the next version, which may be specified as a semver
+// version number or anything `npm version` recognizes. This
+// is a "pre-release" if nextVersion is premajor, preminor,
+// prepatch, or prerelease
+const nextVersion = prompt(`Next version (current version is ${getPackageVersion()})? `)
+const isPrerelease = nextVersion.substr(0, 3) === 'pre' || nextVersion.indexOf('-') !== -1
+
+// 1) Make sure the tests pass
+exec('npm test -- --single-run')
+
+// 2) Increment the package version in package.json
+// 3) Create a new commit
+// 4) Create a v* tag that points to that commit
+exec(`npm version ${nextVersion} -m "Version %s"`)
+
+// 5) Push to the same branch on the git remote (GitHub).
+// Do this before we publish in case anyone has pushed
+// since we last pulled
+exec('git push origin')
+
+// 6) Publish to npm. Use the "next" tag for pre-releases,
+// "latest" for all others
+exec(`npm publish --tag ${isPrerelease ? 'next' : 'latest'}`)
+
+// 7) Push the v* tag to GitHub
+exec(`git push -f origin v${getPackageVersion()}`)
+
+// 8) Push the "latest" tag to GitHub
+if (!isPrerelease) {
+  exec('git tag -f latest')
+  exec('git push -f origin latest')
+}