implements test for #336, works.

tests/timelines.test.js

@@ -0,0 +1,120 @@
+const root = '../';
+
+beforeEach(function(){
+  require(root + 'jspsych.js');
+  require(root + 'plugins/jspsych-text.js');
+});
+
+describe('loop function', function(){
+
+  test('repeats a timeline when returns true', function(){
+
+    var count = 0;
+
+    var trial = {
+      timeline: [{
+        type: 'text',
+        text: 'foo'
+      }],
+      loop_function: function(){
+        if(count < 1){
+          count++;
+          return true;
+        } else {
+          return false;
+        }
+      }
+    }
+
+    jsPsych.init({
+      timeline: [trial]
+    });
+
+    // first trial
+    document.dispatchEvent(new KeyboardEvent('keydown', {keyCode: 32}));
+    document.dispatchEvent(new KeyboardEvent('keyup', {keyCode: 32}));
+
+    expect(jsPsych.data.get().count()).toBe(1);
+
+    // second trial
+    document.dispatchEvent(new KeyboardEvent('keydown', {keyCode: 32}));
+    document.dispatchEvent(new KeyboardEvent('keyup', {keyCode: 32}));
+
+    expect(jsPsych.data.get().count()).toBe(2);
+
+  });
+
+  test('does not repeat when returns false', function(){
+
+    var count = 0;
+
+    var trial = {
+      timeline: [{
+        type: 'text',
+        text: 'foo'
+      }],
+      loop_function: function(){
+        return false
+      }
+    }
+
+    jsPsych.init({
+      timeline: [trial]
+    });
+
+    // first trial
+    document.dispatchEvent(new KeyboardEvent('keydown', {keyCode: 32}));
+    document.dispatchEvent(new KeyboardEvent('keyup', {keyCode: 32}));
+
+    expect(jsPsych.data.get().count()).toBe(1);
+
+    // second trial
+    document.dispatchEvent(new KeyboardEvent('keydown', {keyCode: 32}));
+    document.dispatchEvent(new KeyboardEvent('keyup', {keyCode: 32}));
+
+    expect(jsPsych.data.get().count()).toBe(1);
+
+  });
+
+  test('gets the data from the most recent iteration', function(){
+
+    var data_count = [];
+    var count = 0;
+
+    var trial = {
+      timeline: [{
+        type: 'text',
+        text: 'foo'
+      }],
+      loop_function: function(data){
+        data_count.push(data.count());
+        if(count < 2){
+          count++;
+          return true;
+        } else {
+          return false;
+        }
+      }
+    }
+
+    jsPsych.init({
+      timeline: [trial]
+    });
+
+    // first trial
+    document.dispatchEvent(new KeyboardEvent('keydown', {keyCode: 32}));
+    document.dispatchEvent(new KeyboardEvent('keyup', {keyCode: 32}));
+
+    // second trial
+    document.dispatchEvent(new KeyboardEvent('keydown', {keyCode: 32}));
+    document.dispatchEvent(new KeyboardEvent('keyup', {keyCode: 32}));
+
+    // third trial
+    document.dispatchEvent(new KeyboardEvent('keydown', {keyCode: 32}));
+    document.dispatchEvent(new KeyboardEvent('keyup', {keyCode: 32}));
+
+    expect(data_count).toEqual([1,1,1]);
+    expect(jsPsych.data.get().count()).toBe(3);
+
+  });
+});