Is there a FxCop rule for local used IDisposable's?

Question

... if I use an IDisposable in a local variable, but do not call Dispose() or use the using() pattern.

public void BadMethod()
{
    var fs = new FileStream("file.txt", FileMode.Create);
    fs.WriteByte(0x55);
    // no dispose, no using()
}

Just like the "Types that own disposable fields should be disposable" rule for fields.

EDIT: Replaced MemoryStream by FileStream, because MemoryStream just allocates memory and doesn't use (unmanaged) resources, so someone could discuss about a mandatory Dispose() call.

Answer 1

Is there an FxCop rule for this? Yes and no.

In FxCop 1.35, which is what Visual Studio 2005 Code Analysis is based on, there was a rule DisposeObjectsBeforeLosingScope which did exactly this.

In FxCop 1.36 (Visual Studio 2008 Code Analysis), they removed their data flow analysis engine, which meant that this rule also had to be removed.

However, in the next FxCop (Visual Studio 2010 Code Analysis), it seems that DisposeObjectsBeforeLosingScope has returned!