add: Mock SPI errors

[2bndy5]

resolves #128

Please review diligently as I'm not overly familiar with this crate's code.

[benjaminschlegel87]

I stumbled across the same problem today and was quite pleased to this was already implemented. As a disclaimer: I got general embedded experience but in terms of idomatic rust I am quite a beginner. Still I reviewed your implementation and the tests. From my POV this looks good and I would have implemented it equally. Would like to see this upstream

[simonsso]

I think this looks good, same kind of implementations as used in I2C.

[simonsso]

Ok then all we need is @dbrgn to get some time and merge this.

[2bndy5]

It's been pending admin review for over half a year. I'm not holding my breathe. Instead, I've been using this from my fork's dev branch (cherry picked commits from this branch and another PR also pending review).

[simonsso]

It's been pending admin review for over half a year. I'm not holding my breathe. Instead, I've been using this from my fork's dev branch (cherry picked commits from this branch and another PR also pending review).

Yes I saw that.

[dbrgn]

It's been pending admin review for over half a year. I'm not holding my breathe. Instead, I've been using this from my fork's dev branch (cherry picked commits from this branch and another PR also pending review).

Yeah, sorry, I haven't had the time to review so far. I will try again to get this project adopted by rust-embedded, in the hope that this will improve things.