imp: in fixed-hash allow opting out rand when std enabled

[Farhad-Shabani]

Closes: #805

[ordian]

This is a breaking change unfortunately.

We'd also need to bump MSRV to 1.60 here according to https://doc.rust-lang.org/cargo/reference/features.html#dependency-features:

Note: The ? syntax is only available starting with Rust 1.60.

We don't have an automatic check for MSRV currently..

[dzmitry-lahoda]

@ordian what is next if you know?

think is that this thing (along with others) hampers adoption of non browser std wasm usage of these things. and before that was annoying in usage in pure parity codebase (that js compilation issue)

[ordian]

@ordian what is next if you know?

think is that this thing (along with others) hampers adoption of non browser std wasm usage of these things. and before that was annoying in usage in pure parity codebase (that js compilation issue)

Tests are failing (exactly because this is a breaking change). They need to be fixed, then it can be merged and later released as a breaking change.

But I am not sure why you are blocked on this. I don't see any std gated code in this crate. Could you just disable std feature and add explicitly crate dependencies you need std features from (e.g. byteorder) with std feature enabled as a workaround?

[dzmitry-lahoda]

When I use this crate with std it makes wasm32 std project fail to compile. If use in wasm32 std but not setting std only on this crates it works. But breaks right away as dep of dep because this crate is used a lot, and sets honestly srt on this crate.
So I am sure cannot use this crate without std because need to make that in all deps, ibc rs, ether abi gen, parity xcm. Impossible.

[ordian]

Yeah, sometimes you can't control which features are selected due to transitive dependencies and cargo's feature unification.

[dzmitry-lahoda]

@Farhad-Shabani

seems tests are failing

   Compiling bounded-collections v0.1.9 (/Users/runner/work/parity-common/parity-common/bounded-collections)
error[E0599]: no function or associated item named `random` found for struct `H256` in the current scope
Error:   --> kvdb-rocksdb/examples/memtest.rs:51:25
   |
51 |         Self::with_seed(H256::random())
   |                               ^^^^^^ function or associated item not found in `H256`

For more information about this error, try `rustc --explain E0599`.
error: could not compile `kvdb-rocksdb` (example "memtest") due to previous error
Error: warning: build failed, waiting for other jobs to finish...
Error: The process '/Users/runner/.cargo/bin/cargo' failed with exit code 101