Move some screen utilities to the global util directory so that they can be used for other things too.

lib/util/riskystream.js

@@ -0,0 +1,35 @@
+var util = require('util')
+
+var EventEmitter = require('eventemitter3').EventEmitter
+
+function RiskyStream(stream) {
+  this.endListener = function() {
+    this.ended = true
+    this.stream.removeListener('end', this.endListener)
+
+    if (!this.expectingEnd) {
+      this.emit('unexpectedEnd')
+    }
+
+    this.emit('end')
+  }.bind(this)
+
+  this.stream = stream
+    .on('end', this.endListener)
+  this.expectingEnd = false
+  this.ended = false
+}
+
+util.inherits(RiskyStream, EventEmitter)
+
+RiskyStream.prototype.end = function() {
+  this.expectEnd()
+  return this.stream.end()
+}
+
+RiskyStream.prototype.expectEnd = function() {
+  this.expectingEnd = true
+  return this
+}
+
+module.exports = RiskyStream