Merge 992e55a into 5753f0e

module/sampleon/index.js

@@ -1,7 +1,8 @@
 var flyd = require('../../lib');
+var R = require('ramda');
 
-module.exports = flyd.curryN(2, function(s1, s2) {
-  return flyd.combine(function() {
-    return s2();
-  }, [s1]);
+module.exports = flyd.curryN(2, function(trigger, source) {
+  return flyd.combine(function(trigger, source, self, changed) {
+    if (R.contains(trigger, changed)) return source();
+  }, [trigger, source]);
 });

module/sampleon/test/index.js

@@ -19,7 +19,7 @@ describe('sample On', function() {
     s1(5)(3);
     assert.deepEqual(result, [1, 1, 1, 6, 6]);
   });
-  it('has not value until value flows on trigger stream', function() {
+  it('has no value until value flows on trigger stream', function() {
     var result = [];
     var s1 = stream();
     var s2 = stream(1);
@@ -33,4 +33,15 @@ describe('sample On', function() {
     s1(5)(3);
     assert.deepEqual(result, [1, 1, 1, 6, 6]);
   });
+  it('does not update until both trigger stream and source stream have been updated', function() {
+    var result = [];
+    var trigger = stream();
+    var source = flyd.combine(function(s1) {return s1();}, [trigger]);
+    var sampled = sampleOn(trigger, source);
+    flyd.map(function(v) {
+      result.push(v);
+    }, sampled);
+    trigger(0);
+    assert.deepEqual(result, [0]);
+  });
 });