reimplemented promised spawn

lib/build.js

@@ -16,7 +16,7 @@ const nodeRepo = 'https://github.com/nodejs/node';
 async function gitClone () {
   const args = [ 'clone', '--progress', nodeRepo, 'node' ];
   const promise = spawn('git', args, { cwd: buildPath });
-  const child = promise.childProcess;
+  const { child } = promise;
 
   const gauge = log.newItem('', 100);
   gauge.enableProgress();

lib/spawn.js

@@ -1,5 +1,14 @@
-import chipo from 'child-process-promise';
+import chipo from 'child_process';
 
-export function spawn (...args) {
-  return chipo.spawn(...args);
+export function spawn (cmd, args, opts) {
+  const child = chipo.spawn(cmd, args, opts);
+  const promise = new Promise((resolve, reject) => {
+    child.on('error', reject);
+    child.on('close', function (code) {
+      if (code) return reject(new Error(`${cmd} failed with code ${code}`));
+      resolve();
+    });
+  });
+  promise.child = child;
+  return promise;
 }

package.json

@@ -12,7 +12,6 @@
     ]
   },
   "dependencies": {
-    "child-process-promise": "2.0.3",
     "expand-template": "1.0.2",
     "fs-promise": "0.5.0",
     "minimist": "1.2.0",