fixing 'end' issue and adding examples and tests

examples/complex.js

@@ -0,0 +1,66 @@
+'use strict';
+
+// demonstrates how to split up generated values into three times as many via async-through
+var nestStream = require('../')
+  , asyncThru = require('async-through')
+  , from = require('from')
+  , sep = '';
+
+var stream = nestStream(getInnerStream, sep);
+
+function getInnerStream (outerVal) {
+  return from([1 + outerVal, 3 + outerVal, 4 + outerVal, 5 + outerVal])
+}
+
+function transform (data) {
+  // ignore queued separators, but queue non-null value to keep stream going
+  if (data === sep) return this.queue(sep);
+
+  setTimeout(function () {
+    this.queue('\nn    : ' + data, true);
+    this.queue('\nn * 2: ' + data * 2, true);
+    this.queue('\nn / 2: ' + data / 2 + '\n');
+  }.bind(this), 100);
+}
+
+
+from([10, 20, 30, 40])
+  .pipe(stream)
+  .pipe(asyncThru(transform))
+  .on('end', function () { console.error('ended') })
+  .pipe(process.stdout);
+
+/* =>
+ *  n    : 11
+ *  n * 2: 22
+ *  n / 2: 5.5
+ *
+ *  n    : 13
+ *  n * 2: 26
+ *  n / 2: 6.5
+ *
+ *  n    : 14
+ *  n * 2: 28
+ *  n / 2: 7
+ *  
+ *  [ ... ]
+ *
+ *  n    : 44
+ *  n * 2: 88
+ *  n / 2: 22
+ *
+ *  n    : 45
+ *  n * 2: 90
+ *  n / 2: 22.5
+ *  ended
+ */
+
+
+
+
+
+
+
+
+
+

examples/custom-sep.js

@@ -0,0 +1,23 @@
+'use strict';
+
+var nestStream = require('../')
+  , through = require('through')
+  , from = require('from');
+
+var stream = nestStream(getInnerStream, '::');
+
+function getInnerStream (outerVal) {
+  return from([1 + outerVal, 3 + outerVal, 4 + outerVal, 5 + outerVal])
+}
+
+function stringify (data) {
+  this.queue(data + ' ');
+}
+
+from([10, 20, 30, 40])
+  .pipe(stream)
+  .pipe(through(stringify))
+  .on('end', function () { console.error('ended') })
+  .pipe(process.stdout);
+
+// => 11 13 14 15 :: 21 23 24 25 :: 31 33 34 35 :: 41 43 44 45 :: ended

examples/simple.js

@@ -0,0 +1,23 @@
+'use strict';
+
+var nestStream = require('../')
+  , through = require('through')
+  , from = require('from');
+
+var stream = nestStream(getInnerStream);
+
+function getInnerStream (outerVal) {
+  return from([1 + outerVal, 3 + outerVal, 4 + outerVal, 5 + outerVal])
+}
+
+function stringify (data) {
+  this.queue(data + ' ');
+}
+
+from([10, 20, 30, 40])
+  .pipe(stream)
+  .pipe(through(stringify))
+  .on('end', function () { console.error('ended') })
+  .pipe(process.stdout);
+
+// => 11 13 14 15  21 23 24 25  31 33 34 35  41 43 44 45  ended

index.js

@@ -8,13 +8,17 @@ var asyncThru = require('async-through');
  * @name exports
  * @function
  * @param getInnerStream {Function} function (outerValue) { .. } that returns a stream generated from the provided value
+ * @param sep {Object} (optional) 
+ *  any non-null object to serve as a separator between values queued for one value piped by the outer stream
+ *  default: ''
  * @return {Stream} that emits a value for each value provided by either of the inner streams
  */
-var go = module.exports = function (getInnerStream) {
+var go = module.exports = function (getInnerStream, sep) {
   var outerStream = asyncThru(onouter);
+  sep = sep || '';
 
   var ondata = function (data) { outerStream.queue(data, true); };
-  var onend  = function () { outerStream.queue(null); }
+  var onend  = function () { outerStream.queue(sep); }
 
   function onouter (data) {
     getInnerStream(data)

package.json

@@ -15,11 +15,16 @@
     "url": "git://github.com/thlorenz/nest-stream.git"
   },
   "homepage": "https://github.com/thlorenz/nest-stream",
-  "dependencies": {},
+  "dependencies": {
+    "async-through": "~0.2.0"
+  },
   "devDependencies": {
     "nave": "~0.4.3",
     "tape": "~1.0.4",
-    "tap": "~0.4.3"
+    "tap": "~0.4.3",
+    "from": "~0.1.3",
+    "through": "~2.3.4",
+    "concat-stream": "~1.0.1"
   },
   "keywords": [],
   "author": {

test/index.js

@@ -0,0 +1,47 @@
+
+'use strict';
+/*jshint asi: true */
+
+var test = require('tape')
+
+var nestStream = require('../')
+  , concatStream = require('concat-stream')
+  , from = require('from');
+
+
+test('\ndefault separator', function (t) {
+
+  var stream = nestStream(getInnerStream);
+  function getInnerStream (outerVal) {
+    return from([1 + outerVal, 3 + outerVal, 4 + outerVal, 5 + outerVal])
+  }
+
+  var ended;
+  from([10, 20, 30, 40])
+    .pipe(stream)
+    .on('end', function () { ended = true })
+    .pipe(concatStream(function (data) {
+      t.ok(ended, 'ended')
+      t.deepEqual(data, [ 11, 13, 14, 15, '', 21, 23, 24, 25, '', 31, 33, 34, 35, '', 41, 43, 44, 45, '' ], 'data')
+      t.end()
+    }))
+})
+
+test('\ncustom separator', function (t) {
+
+  var sep = 'o/';
+  var stream = nestStream(getInnerStream, sep);
+  function getInnerStream (outerVal) {
+    return from([1 + outerVal, 3 + outerVal, 4 + outerVal, 5 + outerVal])
+  }
+
+  var ended;
+  from([10, 20, 30 ])
+    .pipe(stream)
+    .on('end', function () { ended = true })
+    .pipe(concatStream(function (data) {
+      t.ok(ended, 'ended')
+      t.deepEqual(data, [ 11, 13, 14, 15, 'o/', 21, 23, 24, 25, 'o/', 31, 33, 34, 35, 'o/' ], 'data')
+      t.end()
+    }))
+})