feat(vhd-cli): repl command

packages/vhd-cli/src/commands/repl.js

@@ -0,0 +1,31 @@
+import { asCallback, fromCallback, fromEvent } from 'promise-toolbox'
+import { getHandler } from '@xen-orchestra/fs'
+import { resolve } from 'path'
+import { start as createRepl } from 'repl'
+import * as Vhd from 'vhd-lib'
+
+export default async args => {
+  const handler = getHandler({ url: 'file://' + process.cwd() })
+  await handler.sync()
+  try {
+    const repl = createRepl({
+      prompt: 'vhd> ',
+    })
+    Object.assign(repl.context, Vhd)
+    repl.context.open = path => new Vhd.Vhd(handler, resolve(path))
+
+    // Make the REPL waits for promise completion.
+    repl.eval = (evaluate => (cmd, context, filename, cb) => {
+      asCallback.call(
+        fromCallback(cb => {
+          evaluate.call(repl, cmd, context, filename, cb)
+        }).then(value => (Array.isArray(value) ? Promise.all(value) : value)),
+        cb
+      )
+    })(repl.eval)
+
+    await fromEvent(repl, 'exit')
+  } finally {
+    await handler.forget()
+  }
+}