Unable to mock subclasses of Bitmap

[weltraumpirat]

I have several subclasses of Bitmap I need to use for a complex pixel transformation, and I've run into the following problem:

• If I use the [Mock] annotation only, the test crashes and complains that the pixelSnapping argument must not be null. The funny thing is: all Bitmap constructor arguments have a default value, and so do the constructor args of my derived class.
• If I use [Mock(args="constructorArgs")], I do not get any errors, and I verified that the constructorArgs function (which returns [null, "auto", true]) is called correctly. But instead of a mock object, null is assigned to the variable.
• I get the same null result if I try nice(Bitmap, "", [null, "auto", true]);

[drewbourne]

In the first case with just [Mock] Mockolate will inject null for all
constructor parameters as the describeType() reflection information does
not indicate which parameters are required or optional. I will be improving
this situation shortly by using the as3-commons-bytecode library for
reflection and proxy generation.

In the second case with [Mock(args="constructorArgs")], it looks like you
are doing the correct thing. I will need to investigate further.

To discuss this issue at a higher level my suggestion is to avoid mocking
the runtime classes, such as Bitmap. Instead introduce an interface for the
manipulations you intend to perform, eg: IPixelTranformable which mirrors
the API of the Bitmap methods you want to use, then type to that interface
instead of the concrete Bitmap class and create a small extention class of
Bitmap which implements the IPixelTransformable.

On Sat, Jun 2, 2012 at 12:58 AM, weltraumpirat <
reply@reply.github.com

wrote:

I have several subclasses of Bitmap I need to use for a complex pixel
transformation, and I've run into the following problem:

• If I use the [Mock] annotation only, the test crashes and complains
  that the pixelSnapping argument must not be null. The funny thing is:
  all Bitmap constructor arguments have a default value, and so do the
  constructor args of my derived class.
• If I use [Mock(args="constructorArgs")], I do not get any errors, and I verified that theconstructorArgsfunction (which returns[null, "auto",
  true]) is called correctly. But instead of a mock object,null` is
  assigned to the variable.
• I get the same null result if I try nice(Bitmap, "", [null, "auto", true]);

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