start readable stream in paused mode

index.js

@@ -83,6 +83,18 @@ function duplex (reader, read) {
 
   if(read) {
     s.sink(read)
+    s.paused = true
+
+    var on = s.on.bind(s)
+    s.on = (event, listener) => {
+      var res = on(event, listener)
+
+      if (event === 'data' && s.paused) {
+        next(s.resume.bind(s))
+      }
+
+      return res
+    }
 
     var pipe = s.pipe.bind(s)
     s.pipe = function (dest, opts) {

test/data-event.js

@@ -0,0 +1,20 @@
+var pull     = require('pull-stream')
+var duplex   = require('../')
+
+var test = require('tape')
+
+test('should start to flow when data listener is added', function (t) {
+  var s = duplex(null, pull(pull.values(['hello'])))
+
+  setTimeout(() => {
+    s.on('data', (d) => {
+      t.equal(d, 'hello')
+      t.end()
+    })
+  }, 100)
+
+  setTimeout(() => {
+    t.fail('data event listener was not invoked')
+    t.end()
+  }, 200)
+})

test/error.js

@@ -12,6 +12,7 @@ tape('test that error is emitted', function (t) {
     t.equal(err, error)
     t.end()
   })
+  s.on('data', () => {})
 })
 
 tape('error when paused', function (t) {