summaryrefslogtreecommitdiffstats
path: root/testing/web-platform/tests/annotation-model/scripts/JSONtest.js
blob: 3ee49b86a8162b86a8d41fe6e31f8e67f770c688 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
/* globals add_completion_callback, Promise, showdown, done, assert_true, Ajv, on_event */

/**
 * Creates a JSONtest object.  If the parameters are supplied
 * it also loads a referenced testFile, processes that file, loads any
 * referenced external assertions, and sets up event listeners to process the
 * user's test data.  The loading is done asynchronously via Promises.  The test
 * button's text is changed to Loading while it is processing, and to "Check
 * JSON" once the data is loaded.
 *
 * @constructor
 * @param {object} params
 * @param {string} [params.test] - object containing JSON test definition
 * @param {string} [params.testFile] - URI of a file with JSON test definition
 * @param {string} params.runTest - IDREF of an element that when clicked will run the test
 * @param {string} params.testInput - IDREF of an element that contains the JSON(-LD) to evaluate against the assertions in the test / testFile
 * @event DOMContentLoaded Calls init once DOM is fully loaded
 * @returns {object} Reference to the new object
 */

function JSONtest(params) {
  'use strict';

  this.Assertions = [];     // object that will contain the assertions to process
  this.AssertionText = "";  // string that holds the titles of all the assertions in use
  this.DescriptionText = "";
  this.Base = null;         // URI "base" for the test suite being run
  this.TestDir = null;      // URI "base" for the test case being run
  this.Params = null;       // paramaters passed in
  this.Promise = null;             // master Promise that resolves when intialization is complete
  this.Properties = null;   // testharness_properties from the opening window
  this.SkipFailures = [];   // list of assertionType values that should be skipped if their test would fail
  this.Test = null;         // test being run
  this.AssertionCounter = 0;// keeps track of which assertion is being processed

  this._assertionCache = [];// Array to put loaded assertions into
  this._assertionText = []; // Array of text or nested arrays of assertions
  this._loading = true;

  showdown.extension('strip', function() {
    return [
    { type: 'output',
      regex: /<p>/,
      replace: ''
    },
    { type: 'output',
      regex: /<\/p>$/,
      replace: ''
    }
    ];
  });


  this.markdown = new showdown.Converter({ extensions: [ 'strip' ] }) ;

  var pending = [] ;

  // set up in case DOM finishes loading early
  pending.push(new Promise(function(resolve) {
    on_event(document, "DOMContentLoaded", function() {
        resolve(true);
    }.bind(this));
  }.bind(this)));

  // create an ajv object that will stay around so that caching
  // of schema that are compiled just works
  this.ajv = new Ajv({allErrors: true, validateSchema: false}) ;

  // determine the base URI for the test collection.  This is
  // the top level folder in the test "document.location"

  var l = document.location;
  var p = l.pathname;
  this.TestDir = p.substr(0, 1+p.lastIndexOf('/'));
  this.Base = p.substr(0, 1+p.indexOf('/', 1));

  // if we are under runner, then there are props in the parent window
  //
  // if "output" is set in that, then pause at the end of running so the output
  // can be analyzed. @@@TODO@@@
  if (window && window.opener && window.opener.testharness_properties) {
    this.Properties = window.opener.testharness_properties;
  }

  this.Params = params;

  // if there is a list of definitions in the params,
  // include them
  if (this.Params.schemaDefs) {
    var defPromise = new Promise(function(resolve, reject) {
      var promisedSchema = this.Params.schemaDefs.map(function(item) {
        return this.loadDefinition(item);
      }.bind(this));

      // Once all the loadAssertion promises resolve...
      Promise.all(promisedSchema)
      .then(function (schemaContents) {
        this.ajv.addSchema(schemaContents);
        resolve(true);
      }.bind(this))
      .catch(function(err) {
        reject(err);
      }.bind(this));
    }.bind(this));
    // these schema need to load up too
    pending.push(defPromise) ;
  }

  // start by loading the test (it might be inline, but
  // loadTest deals with that
  pending.push(this.loadTest(params)
    .then(function(test) {
      // if the test is NOT an object, turn it into one
      if (typeof test === 'string') {
        test = JSON.parse(test) ;
      }

      this.Test = test;

      // Test should have information that we can put in the template

      if (test.description) {
        this.DescriptionText = test.description;
      }

      if (test.hasOwnProperty("skipFailures") && Array.isArray(test.skipFailures) ) {
        this.SkipFailures = test.skipFailures;
      }

      if (test.content) {
        // we have content
        if (typeof test.content === "string") {
          // the test content is a string - meaning it is a reference to a file of content
          var cPromise = new Promise(function(resolve, reject) {
            this.loadDefinition(test.content)
              .then(function(content) {
                if (typeof content === 'string') {
                  content = JSON.parse(content) ;
                }
                test.content = content;
                resolve(true);
              }.bind(this))
            .catch(function(err) {
              reject("Loading " + test.content + ": " + JSON.stringify(err));
            });

          }.bind(this));
          pending.push(cPromise);
        }
      }

      return new Promise(function(resolve, reject) {
        if (test.assertions &&
            typeof test.assertions === "object") {
          // we have at least one assertion
          // get the inline contents and the references to external files
          var assertFiles = this._assertionRefs(test.assertions);

          var promisedAsserts = assertFiles.map(function(item) {
            return this.loadAssertion(item);
          }.bind(this));

          // Once all the loadAssertion promises resolve...
          Promise.all(promisedAsserts)
          .then(function (assertContents) {
            // assertContents has assertions in document order

            var typeMap = {
              'must'   : "<b>[MANDATORY]</b> ",
              'may'    : "<b>[OPTIONAL]</b> ",
              'should' : "<b>[RECOMMENDED]</b> "
            };

            var assertIdx = 0;

            // populate the display of assertions that are being exercised
            // returns the list of top level assertions to walk through

            var buildList = function(assertions, level) {
              if (level === undefined) {
                level = 1;
              }

              // accumulate the assertions - but only when level is 0
              var list = [] ;

              var type = "";
              if (assertions) {
                if (typeof assertions === "object" && assertions.hasOwnProperty('assertions')) {
                  // this is a conditionObject
                  if (level === 0) {
                    list.push(assertContents[assertIdx]);
                  }
                  type = assertContents[assertIdx].hasOwnProperty('assertionType') ?
                    assertContents[assertIdx].assertionType : "must" ;

                  // ensure type defaults to must
                  if (!typeMap.hasOwnProperty(type)) {
                    type = "must";
                  }

                  this.AssertionText += "<li>" + typeMap[type] + this.markdown.makeHtml(assertContents[assertIdx++].title);
                  this.AssertionText += "<ol>";
                  buildList(assertions.assertions, level+1) ;
                  this.AssertionText += "</ol></li>\n";
                } else {
                  // it is NOT a conditionObject - must be an array
                  assertions.forEach( function(assert) {
                    if (typeof assert === "object" && Array.isArray(assert)) {
                      this.AssertionText += "<ol>";
                      // it is a nested list - recurse
                      buildList(assert, level+1) ;
                      this.AssertionText += "</ol>\n";
                    } else if (typeof assert === "object" &&
                        !Array.isArray(assert) &&
                        assert.hasOwnProperty('assertions')) {
                      if (level === 0) {
                        list.push(assertContents[assertIdx]);
                      }
                      type = assertContents[assertIdx].hasOwnProperty('assertionType') ?
                        assertContents[assertIdx].assertionType : "must" ;

                      // ensure type defaults to must
                      if (!typeMap.hasOwnProperty(type)) {
                        type = "must";
                      }

                      // there is a condition object in the array
                      this.AssertionText += "<li>" + typeMap[type] + this.markdown.makeHtml(assertContents[assertIdx++].title);
                      this.AssertionText += "<ol>";
                      buildList(assert, level+1) ; // capture the children too
                      this.AssertionText += "</ol></li>\n";
                    } else {
                      if (level === 0) {
                        list.push(assertContents[assertIdx]);
                      }
                      type = assertContents[assertIdx].hasOwnProperty('assertionType') ?
                        assertContents[assertIdx].assertionType : "must" ;

                      // ensure type defaults to must
                      if (!typeMap.hasOwnProperty(type)) {
                        type = "must";
                      }

                      this.AssertionText += "<li>" + typeMap[type] + this.markdown.makeHtml(assertContents[assertIdx++].title) + "</li>\n";
                    }
                  }.bind(this));
                }
              }
              return list;
            }.bind(this);

            // Assertions will ONLY contain the top level assertions
            this.Assertions = buildList(test.assertions, 0);
            resolve(true);
          }.bind(this))
          .catch(function(err) {
            reject(err);
          }.bind(this));
        } else {
          if (!test.assertions) {
            reject("Test has no assertion property");
          } else {
            reject("Test assertion property is not an Array");
          }
        }
      }.bind(this));
    }.bind(this)));

  this.Promise = new Promise(function(resolve, reject) {
    // once the DOM and the test / assertions are loaded... set us up
    Promise.all(pending)
    .then(function() {
      this.loading = false;
      this.init();
      resolve(this);
    }.bind(this))
    .catch(function(err) {
      // loading the components failed somehow - report the errors and mark the test failed
      test( function() {
        assert_true(false, "Loading of test components failed: " +JSON.stringify(err)) ;
      }, "Loading test components");
      done() ;
      reject("Loading of test components failed: "+JSON.stringify(err));
      return ;
    }.bind(this));
  }.bind(this));

  return this;
}

JSONtest.prototype = {

  /**
   * @listens click
   */
  init: function() {
    'use strict';
    // set up a handler
    var runButton = document.getElementById(this.Params.runTest) ;
    var closeButton = document.getElementById(this.Params.closeWindow) ;
    var testInput  = document.getElementById(this.Params.testInput) ;
    var assertion  = document.getElementById("assertion") ;
    var desc  = document.getElementById("testDescription") ;

    if (!this.loading) {
      if (runButton) {
        runButton.disabled = false;
        runButton.value = "Check JSON";
      }
      if (desc) {
        desc.innerHTML = this.DescriptionText;
      }
      if (assertion) {
        assertion.innerHTML = "<ol>" + this.AssertionText + "</ol>\n";
      }
    } else {
      window.alert("Loading did not finish before init handler was called!");
    }

    // @@@TODO@@@ implement the output showing handler
    if (0 && this.Properties && this.Properties.output && closeButton) {
      // set up a callback
      add_completion_callback( function() {
        var p = new Promise(function(resolve) {
          closeButton.style.display = "inline";
          closeButton.disabled = false;
          on_event(closeButton, "click", function() {
            resolve(true);
          });
        }.bind(this));
        p.then();
      }.bind(this));
    }

    if (runButton) {
      on_event(runButton, "click", function() {
        // user clicked
        var content = testInput.value;
        runButton.disabled = true;

        // make sure content is an object
        if (typeof content === "string") {
          try {
            content = JSON.parse(content) ;
          } catch(err) {
            // if the parsing failed, create a special test and mark it failed
            test( function() {
              assert_true(false, "Parse of JSON failed: " + err) ;
            }, "Parsing submitted input");
            // and just give up
            done();
            return ;
          }
        }

        // iterate over all of the tests for this instance
        this.runTests(this.Assertions, content);

        // explicitly tell the test framework we are done
        done();
      }.bind(this));
    }
  },

  // runTests - process tests
  /**
   * @param {object} assertions - List of assertions to process
   * @param {string} content - JSON(-LD) to be evaluated
   * @param {string} [testAction='continue'] - state of test processing (in parent when recursing)
   * @param {integer} [level=0] - depth of recursion since assertion lists can nest
   * @param {string} [compareWith='and'] - the way the results of the referenced assertions should be compared
   * @returns {string} - the testAction resulting from evaluating all of the assertions
   */
  runTests: function(assertions, content, testAction, level, compareWith) {
    'use strict';

    // level
    if (level === undefined) {
      level = 1;
    }

    // testAction
    if (testAction === undefined) {
      testAction = 'continue';
    }

    // compareWith
    if (compareWith === undefined) {
      compareWith = 'and';
    }

    var typeMap = {
      'must'   : "",
      'may'    : "INFORMATIONAL: ",
      'should' : "WARNING: "
    };


    // for each assertion (in order) load the external json schema if
    // one is referenced, or use the inline schema if supplied
    // validate content against the referenced schema

    var theResults = [] ;

    if (assertions) {

      assertions.forEach( function(assert, num) {

        var expected = assert.hasOwnProperty('expectedResult') ?
          assert.expectedResult : 'valid' ;
        var message = assert.hasOwnProperty('errorMessage') ?
          assert.errorMessage : "Result was not " + expected;
        var type = assert.hasOwnProperty('assertionType') ?
          assert.assertionType.toLowerCase() : "must" ;
        if (!typeMap.hasOwnProperty(type)) {
          type = "must";
        }

        // first - what is the type of the assert
        if (typeof assert === "object" && !Array.isArray(assert)) {
          if (assert.hasOwnProperty("compareWith") && assert.hasOwnProperty("assertions") && Array.isArray(assert.assertions) ) {
            // this is a comparisonObject
            var r = this.runTests(assert.assertions, content, testAction, level+1, assert.compareWith);
            // r is an object that contains, among other things, an array of results from the child assertions
            testAction = r.action;

            // evaluate the results against the compareWith setting
            var result = true;
            var data = r.results ;
            var i;

            if (assert.compareWith === "or") {
              result = false;
              for(i = 0; i < data.length; i++) {
                if (data[i]) {
                  result = true;
                }
              }
            } else {
              for(i = 0; i < data.length; i++) {
                if (!data[i]) {
                  result = false;
                }
              }
            }

            // create a test and push the result
            test(function() {
              var newAction = this.determineAction(assert, result) ;
              // next time around we will use this action
              testAction = newAction;

              var err = ";";

              if (testAction === 'abort') {
                err += "; Aborting execution of remaining assertions;";
              } else if (testAction === 'skip') {
                err += "; Skipping execution of remaining assertions at level " + level + ";";
              }

              if (result === false) {
                // test result was unexpected; use message
                assert_true(result, message + err);
              } else {
                assert_true(result, err) ;
              }
            }.bind(this), "" + level + ":" + (num+1) + " " + assert.title);
            // we are going to return out of this
            return;
          }
        } else if (typeof assert === "object" && Array.isArray(assert)) {
          // it is a nested list - recurse
          var o = this.runTests(assert, content, testAction, level+1);
          if (o.result && o.result === 'abort') {
            // we are bailing out
            testAction = 'abort';
          }
        }

        if (testAction === 'abort') {
          return {action: 'abort' };
        }

        var schemaName = "inline " + level + ":" + (num+1);

        if (typeof assert === "string") {
          // the assertion passed in is a file name; find it in the cache
          if (this._assertionCache[assert]) {
            assert = this._assertionCache[assert];
          } else {
            test( function() {
              assert_true(false, "Reference to assertion " + assert + " at level " + level + ":" + (num+1) + " unresolved") ;
            }, "Processing " + assert);
            return ;
          }
        }

        if (assert.assertionFile) {
          schemaName = "external file " + assert.assertionFile + " " + level + ":" + (num+1);
        }

        var validate = null;

        try {
          validate = this.ajv.compile(assert);
        }
        catch(err) {
          test( function() {
            assert_true(false, "Compilation of schema " + level + ":" + (num+1) + " failed: " + err) ;
          }, "Compiling " + schemaName);
          return ;
        }

        if (testAction === 'continue') {
          // a previous test told us to not run this test; skip it
          // test(function() { }, "SKIPPED: " + assert.title);
          // start an actual sub-test
          var valid = validate(content) ;

          var theResult = this.determineResult(assert, valid) ;

          // remember the result
          theResults.push(theResult);

          var newAction = this.determineAction(assert, theResult) ;
          // next time around we will use this action
          testAction = newAction;

          // only run the test if we are NOT skipping fails for some types
          // or the result is expected
          if ( theResult === true || !this.SkipFailures.includes(type) ) {
            test(function() {
              var err = ";";
              if (validate.errors !== null && !assert.hasOwnProperty("errorMessage")) {
                err = "; Errors: " + this.ajv.errorsText(validate.errors) + ";" ;
              }
              if (testAction === 'abort') {
                err += "; Aborting execution of remaining assertions;";
              } else if (testAction === 'skip') {
                err += "; Skipping execution of remaining assertions at level " + level + ";";
              }
              if (theResult === false) {
                // test result was unexpected; use message
                assert_true(theResult, typeMap[type] + message + err);
              } else {
                assert_true(theResult, err) ;
              }
            }.bind(this), "" + level + ":" + (num+1) + " " + assert.title);
          }
        }
      }.bind(this));
    }

    return { action: testAction, results: theResults} ;
  },

  determineResult: function(schema, valid) {
    'use strict';
    var r = 'valid' ;
    if (schema.hasOwnProperty('expectedResult')) {
      r = schema.expectedResult;
    }

    if (r === 'valid' && valid || r === 'invalid' && !valid) {
      return true;
    } else {
      return false;
    }
  },

  determineAction: function(schema, result) {
    'use strict';
    // mapping from results to actions
    var mapping = {
      'failAndContinue' : 'continue',
      'failAndSkip'    : 'skip',
      'failAndAbort'   : 'abort',
      'passAndContinue': 'continue',
      'passAndSkip'    : 'skip',
      'passAndAbort'   : 'abort'
    };

    // if the result was as expected, then just keep going
    if (result) {
      return 'continue';
    }

    var a = 'failAndContinue';

    if (schema.hasOwnProperty('onUnexpectedResult')) {
      a = schema.onUnexpectedResult;
    }

    if (mapping[a]) {
      return mapping[a];
    } else {
      return 'continue';
    }
  },

  // loadAssertion - load an Assertion from an external JSON file
  //
  // returns a promise that resolves with the contents of the assertion file

  loadAssertion: function(afile) {
    'use strict';
    if (typeof(afile) === 'string') {
      var theFile = this._parseURI(afile);
      // it is a file reference - load it
      return new Promise(function(resolve, reject) {
        this._loadFile("GET", theFile, true)
          .then(function(data) {
            data.assertionFile = afile;
            this._assertionCache[afile] = data;
            resolve(data);
          }.bind(this))
          .catch(function(err) {
            if (typeof err === "object") {
              err.theFile = theFile;
            }
            reject(err);
          });
        }.bind(this));
      }
      else if (afile.hasOwnProperty("assertionFile")) {
      // this object is referecing an external assertion
      return new Promise(function(resolve, reject) {
        var theFile = this._parseURI(afile.assertionFile);
        this._loadFile("GET", theFile, true)
        .then(function(external) {
          // okay - we have an external object
          Object.keys(afile).forEach(function(key) {
            if (key !== 'assertionFile') {
              external[key] = afile[key];
            }
          });
          resolve(external);
        }.bind(this))
        .catch(function(err) {
          if (typeof err === "object") {
            err.theFile = theFile;
          }
          reject(err);
        });
      }.bind(this));
    } else {
      // it is already a loaded assertion - just use it
      return new Promise(function(resolve) {
        resolve(afile);
      });
    }
  },

  // loadDefinition - load a JSON Schema definition from an external JSON file
  //
  // returns a promise that resolves with the contents of the definition file

  loadDefinition: function(dfile) {
    'use strict';
    return new Promise(function(resolve, reject) {
      this._loadFile("GET", this._parseURI(dfile), true)
        .then(function(data) {
          resolve(data);
        }.bind(this))
        .catch(function(err) {
          reject(err);
        });
      }.bind(this));
  },


  // loadTest - load a test from an external JSON file
  //
  // returns a promise that resolves with the contents of the
  // test

  loadTest: function(params) {
    'use strict';

    if (params.hasOwnProperty('testFile')) {
      // the test is referred to by a file name
      return this._loadFile("GET", params.testFile);
    } // else
    return new Promise(function(resolve, reject) {
      if (params.hasOwnProperty('test')) {
        resolve(params.test);
      } else {
        reject("Must supply a 'test' or 'testFile' parameter");
      }
    });
  },

  _parseURI: function(theURI) {
    'use strict';
    // determine what the top level URI should be
    if (theURI.indexOf('/') === -1) {
      // no slash - it's relative to where we are
      // so just use it
      return this.TestDir + theURI;
    } else if (theURI.indexOf('/') === 0 || theURI.indexOf('http:') === 0 || theURI.indexOf('https:') === 0) {
      // it is an absolute URI so just use it
      return theURI;
    } else {
      // it is relative and contains a slash.
      // make it relative to the current test root
      return this.Base + theURI;
    }
  },

  /**
   * return a list of all inline assertions or references
   *
   * @param {array} assertions list of assertions to examine
   */

  _assertionRefs: function(assertions) {
    'use strict';
    var ret = [] ;

    // when the reference is to an object that has an array of assertions in it (a conditionObject)
    // then remember that one and loop over its embedded assertions
    if (typeof(assertions) === "object" && !Array.isArray(assertions) && assertions.hasOwnProperty('assertions')) {
      ret.push(assertions) ;
      assertions = assertions.assertions;
    }
    if (typeof(assertions) === "object" && Array.isArray(assertions)) {
      assertions.forEach( function(assert) {
        // first - what is the type of the assert
        if (typeof assert === "object" && Array.isArray(assert)) {
          // it is a nested list - recurse
          this._assertionRefs(assert).forEach( function(item) {
            ret.push(item);
          }.bind(this));
        } else if (typeof assert === "object") {
          ret.push(assert) ;
          if (assert.hasOwnProperty("assertions")) {
            // there are embedded assertions; get those too
            ret.concat(this._assertionRefs(assert.assertions));
          }
        } else {
          // it is a file name
          ret.push(assert) ;
        }
      }.bind(this));
    }
    return ret;
  },

  // _loadFile - return a promise loading a file
  //
  _loadFile: function(method, url, parse) {
    'use strict';
    if (parse === undefined) {
      parse = true;
    }

    return new Promise(function (resolve, reject) {
      if (document.location.search) {
        var s = document.location.search;
        s = s.replace(/^\?/, '');
        if (url.indexOf('?') !== -1) {
          url += "&" + s;
        } else {
          url += "?" + s;
        }
      }
      var xhr = new XMLHttpRequest();
      xhr.open(method, url);
      xhr.onload = function () {
        if (this.status >= 200 && this.status < 300) {
          var d = xhr.response;
          if (parse) {
            try {
              d = JSON.parse(d);
              resolve(d);
            }
            catch(err) {
              reject({ status: this.status,
                       statusText: "Parsing of " + url + " failed: " + err }
                   );
            }
          } else {
            resolve(d);
          }
        } else {
          reject({
            status: this.status,
            statusText: xhr.statusText
          });
        }
      };
      xhr.onerror = function () {
        reject({
          status: this.status,
          statusText: xhr.statusText
        });
      };
      xhr.send();
    });
  },

};