Make bytes dependency optional

[jklmnn]

ref #51

[00imvj00]

@jklmnn Builds are failing, here is the error. please check?

[jklmnn]

The problem seems to be that bytes are used in the tests and are not available with no_std. We could either add it as a test dependency or modify the tests to work without it (which I would prefer since we want to check that it works without it).

There are 2 instances I have identified so far. The first one is the one in your screenshot. Here I'm not sure what the intention is.

mqttrs/src/decoder_test.rs

Line 118 in 0f1ce9d

let mut data = bm(&[

is the only use of bytes in decoder_test. Since the test input is the same for the version with and without bytes my guess is that it is intended. I made this test dependent on std which seems to fix it.

The other problems are the examples. E.g.

mqttrs/src/decoder.rs

Line 70 in 0f1ce9d

/// # use mqttrs::*;

. We either have to adapt them to work without bytes or make them work without it. Since the only reason for bytes here seems to be the test data (and the example on how to use bytes with the API) I think we could remove them. But I don't have a really strong opinion on that.

I haven't looked into how bytes is used internally. From a users perspective I found the bytes reference in the documentation rather confusing since it doesn't seem to be required for it to work. If you want I can remove bytes from the examples but this is really a design decision. If you want to keep bytes in them I think we have to disable the examples for the no_std tests.

[mchodzikiewicz]

You can disable doctests for specific cfg like this: https://users.rust-lang.org/t/how-to-disable-documentation-testing-for-specific-platforms/5059

[jklmnn]

@mchodzikiewicz I have disabled the doc tests in the workflow itself by running them with --tests --lib.

@00imvj00 the tests should work now. I have also added a check running cargo fmt and formatted the code with it. Let me know if that is okay for you.