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JavaScript

// ResultFormatter class, before we implement interface checking.
var ResultFormatter = function(resultsObject) {
    if (!(resultsObject instanceOf TestResult)) {
        throw new Error("ResultsFormatter: constructor requires an instance " + "of TestResult as an argument.");
    }

    this.resultsObject = resultsObject;
};

ResultFormatter.prototype.renderResults = function() {
    var dateOfTest = this.resultsObject.getDate();
    var resultsArray = this.resultsObject.getResults();
    var resultsContainer = document.createElement('div');
    var resultsHeader = document.createElement('h3');
    resultsHeader.innerHTML = 'Test Results from ' + dateOfTest.toUTCString();
    resultsContainer.appendChild(resultsHeader);
    var resultsList = document.createElement('ul');
    resultsContainer.appendChild(resultsList);

    for (var i = 0, len = resultsArray.length; i < len; i++) {
        var listItem = document.createElement('li');
        listItem.innerHTML = resultsArray[i];
        resultsList.appendChild(listItem);
    }

    return resultsContainer;
};