Databases
StackOverflow2013
Postsdbo
POHow to write a generic test method to ensure that a class has a subset of properties of a separate class?
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POHow to write a generic test method to ensure that a class has a subset of properties of a separate class?
    primarykey
    data
    text
    <p>I am endeavoring to write a test method to determine if a class has a superset of properties of a different class. This is for purposes of mapping from domain objects to view model objects and as such there is no relationship between the two classes.</p> <p>As an example if I had the domain class <code>Foo</code> and the view model class <code>FooMap</code> I would want to test that <code>Foo</code> had the properties that <code>FooMap</code> expected it to.</p> <pre><code>public class Foo { public string Bar { get;set; } public string Baz { get;set; } public string NoOneCaresProp { get; set; } public string GetBarBaz() { return Bar + Baz; } } public class FooMap { public string Bar { get; set; } public string GetBarBaz { get; set; } public string NotAFooProp { get; set; } } </code></pre> <p>Given the properties of <code>FooMap</code> for the purposes of this test I want to ensure that class <code>Foo</code> has the <code>Bar</code> property and the <code>GetBarBaz</code> method. Additional methods or properties for either class should be ignored. I've written the following static method to perform such a test but am not happy with my implementation:</p> <pre><code>public static void ExpectedPropertiesExist&lt;TSource, TDestination, R&gt;(params Expression&lt;Func&lt;TDestination, R&gt;&gt;[] exclude) { var excludedProperties = exclude.Select(e =&gt; (e.Body as MemberExpression).Member.Name); var mappedProperties = typeof(TDestination).GetProperties() .Select(p =&gt; p.Name) .Except(excludedProperties); var sourceType = typeof(TSource); var baseTypeNames = sourceType.GetProperties().Select(b =&gt; b.Name).ToList(); baseTypeNames.AddRange(sourceType.GetMethods().Select(b =&gt; b.Name)); Assert.IsTrue(new HashSet&lt;string&gt;(baseTypeNames) .IsSupersetOf(mappedProperties)); } </code></pre> <p>The code to call the above is not nearly as succinct as I would like it to be: </p> <pre><code>// what my call to the function looks like now TestExtensionFun.ExpectedPropertiesExist&lt;Foo, FooMap, object&gt;(fm =&gt; fm.NotAFooProp); // I'd prefer it to look like this TestExtensionFun.ExpectedPropertiesExist&lt;Foo, FooMap&gt;(fm =&gt; fm.NotAFooProp); </code></pre> <p>Nor am I sure that the method is as proficient as it could be. What is the best mechanism to write a generic test method to ensure that a class has a subset of properties of a separate class?</p>
    singulars
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PTQuestion
    1. This table or related slice is empty.
    1. USahsteele
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POHow to write a generic test method to ensure that a class has a subset of properties of a separate class?
      1. This table or related slice is empty.
      1. VTUpMod
    1. COTrying taking a look at the [FluentAssertions](http://fluentassertions.codeplex.com/documentation) library on [CodePlex](http://fluentassertions.codeplex.com/documentation). It gives you some powerful property assertions that you have lots of control over.
      singulars
      1. POHow to write a generic test method to ensure that a class has a subset of properties of a separate class?
      1. USnithins
    2. COCurious, is the code outside of your control? Why not just enforce it at compile time with an interface?
      singulars
      1. POHow to write a generic test method to ensure that a class has a subset of properties of a separate class?
      1. UScasperOne
    3. CO@casperOne I could enforce it with an interface but then my domain object has the potential to become cluttered with interface implementations for each view model that might map from it.
      singulars
      1. POHow to write a generic test method to ensure that a class has a subset of properties of a separate class?
      1. USahsteele
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload