How to omit auto-properties when building an object?

[jzabroski]

For really large object graphs with lots of top-level properties, where I only care about about one path through the object graph, it would be nice to write this:

Fixture.Build<Foo>(omitAutoProperties: true)
  .With(s => s.PropertyICareAbout, Fixture.Create<PropertyICareAbout>())
  .Create();

The advantage is that the omission is scoped to the Build command, so the context is captured under which auto-properties should be omitted. I don't like writing this, since it mutates global state and doesn't tie that mutation to a particular reason:

Fixture.OmitAutoProperties = true;
Fixture.Build<Foo>()
  .With(s => s.PropertyICareAbout, Fixture.Create<PropertyICareAbout>())
  .Create();
Fixture.OmitAutoProperties = false;

I actually have been using AutoFixture for about 4 years and never realized what auto properties were, until I read #222

[aivascu]

@jzabroski this functionality is already present in AutoFixture. It is enabled via the OmitAutoProperties() method of the
IPostprocessComposer<T>.

[Fact]
public void Foo()
{
    var fixture = new Fixture();

    var person = fixture.Build<Person>()
        .OmitAutoProperties()
        .With(x => x.Photo, fixture.Create<Photo>())
        .Create();

    Assert.NotNull(person.Photo);
    Assert.Null(person.FirstName);
}

You can also selectively omit specific properties using the .Without() method while using Build<T>().