Unit testing XML Generation [closed]

Answer 1

Another possibility might be to use XmlReader and check for an error count > 0. Something like this:

    void CheckXml()
    {
        string _xmlFile = "this.xml";
        string _xsdFile = "schema.xsd"; 
        StringCollection _xmlErrors = new StringCollection();

        XmlReader reader = null;
        XmlReaderSettings settings = new XmlReaderSettings();
        settings.ValidationEventHandler += new ValidationEventHandler(this.ValidationEventHandler);
        settings.ValidationType = ValidationType.Schema;
        settings.IgnoreComments = chkIgnoreComments.Checked;
        settings.IgnoreProcessingInstructions = chkIgnoreProcessingInstructions.Checked;
        settings.IgnoreWhitespace = chkIgnoreWhiteSpace.Checked;
        settings.Schemas.Add(null, XmlReader.Create(_xsdFile));
        reader = XmlReader.Create(_xmlFile, settings);
        while (reader.Read())
        {
        }
        reader.Close();
        Assert.AreEqual(_xmlErrors.Count,0);
    }    

    void ValidationEventHandler(object sender, ValidationEventArgs args)
    {
        _xmlErrors.Add("<" + args.Severity + "> " + args.Message);
    }

Answer 2

Fluent Assertions is an excellent library for expressing test assertions in a fluent, easy to read style. It works with all the major Unit Testing frameworks.

It also has some useful XML functionality (all taken from the examples here), for example:

xElementA.Should().Be(xElementB);

xDocument.Should().HaveRoot("configuration");
xDocument.Should().HaveElement("settings");

xElement.Should().HaveAttribute("age", "36");
xElement.Should().HaveElement("address");

xAttribute.Should().HaveValue("Amsterdam");

Note that this works with LINQ-To-XML rather than the XmlDocument object specified in the original question but personally these days I find I'm using LINQ-To-XML as a first choice.

It is also quite easily extensible, should you want to add further XML assertions to fit your needs.

Answer 3

XMLUnit may help you.

Answer 4

Validate against XML schema or DTD, also check key that nodes have the values you expect.

Answer 5

If you have a standard format that you expect the output to be, why not create an XML schema or DTD and validate against that. This won't depend on the data, so will be flexible. Also defining how the XML can be formed can be helpful when designing you system.

Answer 6

First, as pretty much everyone is saying, validate the XML if there's a schema defined for it. (If there's not, define one.)

But you can build tests that are a lot more granular than that by executing XPath queries against the document, e.g.:

string xml="Your xml string here" ;
XmlDocument doc = new XmlDocument();
doc.LoadXml(xml);
path = "/doc/element1[@id='key1']/element2[. = 'value2']";
Assert.IsTrue(doc.SelectSingleNode(path) != null);

This lets you test not only whether or not your document is semantically valid, but whether or not the method producing it is populating it with the values that you expect.