implements a first pass at #1237

jspsych.js

@@ -334,6 +334,10 @@ window.jsPsych = (function() {
     }
   }
 
+  core.allTimelineVariables = function(){
+    return timeline.allTimelineVariables();
+  }
+
   core.addNodeToEndOfTimeline = function(new_timeline, preload_callback){
     timeline.insert(new_timeline);
     if(typeof preload_callback !== 'undefined'){
@@ -617,6 +621,42 @@ window.jsPsych = (function() {
       }
     }
 
+    // recursively get all the timeline variables for this trial
+    this.allTimelineVariables = function(){
+      var all_tvs = this.allTimelineVariablesNames();
+      var all_tvs_vals = {};
+      for(var i=0; i<all_tvs.length; i++){
+        all_tvs_vals[all_tvs[i]] = this.timelineVariable(all_tvs[i])
+      }
+      return all_tvs_vals;
+    }
+
+    // helper to get all the names at this stage.
+    this.allTimelineVariablesNames = function(so_far){
+      if(typeof so_far == 'undefined'){
+        so_far = [];
+      }
+      if(typeof timeline_parameters !== 'undefined'){
+        so_far = so_far.concat(Object.keys(timeline_parameters.timeline_variables[progress.order[progress.current_variable_set]]));
+        // if progress.current_location is -1, then the timeline variable is being evaluated
+        // in a function that runs prior to the trial starting, so we should treat that trial
+        // as being the active trial for purposes of finding the value of the timeline variable
+        var loc = Math.max(0, progress.current_location);
+        // if loc is greater than the number of elements on this timeline, then the timeline
+        // variable is being evaluated in a function that runs after the trial on the timeline
+        // are complete but before advancing to the next (like a loop_function).
+        // treat the last active trial as the active trial for this purpose.
+        if(loc == timeline_parameters.timeline.length){
+          loc = loc - 1;
+        }
+        // now find the variable
+        return timeline_parameters.timeline[loc].allTimelineVariablesNames(so_far);
+      }
+      if(typeof timeline_parameters == 'undefined'){
+        return so_far;
+      }
+    }
+
     // recursively get the number of **trials** contained in the timeline
     // assuming that while loops execute exactly once and if conditionals
     // always run

tests/jsPsych/timeline-variables.test.js

@@ -252,3 +252,33 @@ describe('timeline variables are correctly evaluated', function(){
 
 
 })
+
+describe('allTimelineVariables', function(){
+  test('gets all timeline variables for a simple timeline', function(){
+    var t = {
+      timeline: [{
+        type: 'html-keyboard-response',
+        stimulus: 'foo',
+        on_finish: function(data){
+          var all_tvs = jsPsych.allTimelineVariables();
+          Object.assign(data, all_tvs);
+        }
+      }],
+      timeline_variables: [
+        {a: 1, b: 2},
+        {a: 2, b: 3}
+      ]
+    }
+
+    jsPsych.init({timeline: [t]});
+
+    utils.pressKey(32);
+    utils.pressKey(32);
+
+    var data = jsPsych.data.get().values();
+    expect(data[0].a).toBe(1);
+    expect(data[0].b).toBe(2);
+    expect(data[1].a).toBe(2);
+    expect(data[1].b).toBe(3);
+  });
+})