Trying to prevent accidental usage of the fuzztarget functions

[elichai]

A suggestion of a way to solve #90

This is a result of a conversation with @real-or-random and some feedback from @TheBlueMatt

The part i'm less sure of is the tests here, because rust tests run in concurrent threads and I want to test both with the bool set and without I had to use some Mutex to make sure they don't run together

Another thing that isn't too nice is that we need to put this is all the fuzzing functions.
if proc macros were stabilized before 1.22 we could've wrote an attribute macro and made it a bit nicer but it would've still required doing it on every function.

[real-or-random]

The part i'm less sure of is the tests here, because rust tests run in concurrent threads and I want to test both with the bool set and without I had to use some Mutex to make sure they don't run together

Well it's not super elegant but it works, so it's good. This is discussed here: rust-lang/rust#43155 This issue has some nice code snippets. The simplest solution is to pass -- --test-threads=1 to cargo test. I think we could actually do that (with a comment that explains it).

[elichai]

Well it's not super elegant but it works, so it's good. This is discussed here: rust-lang/rust#43155 This issue has some nice code snippets. The simplest solution is to pass -- --test-threads=1 to cargo test. I think we could actually do that (with a comment that explains it).

That's cool :) did not know about this flag.

overlooked a nit

[elichai]

Rebased, and replaced the -- --test-threads=1 trick with just running them both in the same single test.

[apoelstra]

Closing, fixed by #263