feat(pre): add initial version of command

src/pre.js

@@ -0,0 +1,26 @@
+'use strict'
+
+var fs = require('fs')
+
+var semver = require('semver')
+
+var type = require('../lib/type')
+var version = require('../lib/version')
+
+module.exports = function (options, cb) {
+  type(function (err, type) {
+    if (err) return cb(err)
+    if (!type) return cb(null, null)
+
+    var path = './package.json'
+    var pkg = JSON.parse(fs.readFileSync(path))
+    version(pkg, function (err, version, unpublished) {
+      if (err) return cb(err)
+
+      pkg.version = unpublished ? '1.0.0' : semver.inc(version, type)
+      if (!options.debug) fs.writeFileSync(path, JSON.stringify(pkg, null, 2))
+
+      cb(null, pkg.version)
+    })
+  })
+}