Wasi run tests

[fengb]

This patches in some missing functionality into std.os.wasi to get tests compiling and running.

$ zig test prototypes/wavesynth/src/main.zig -target wasm32-wasi --test-cmd wasmtime --test-cmd-bin
1/3 test "Note.parse"...OK
2/3 test "Note.toFreq"...OK
3/3 test "Note.format"...OK
All tests passed.

[daurnimator]

Would this be better done on the DirectAllocator type itself?

[fengb]

I'm not sure. Since the wasm allocator has global state, we need to ensure that direct_allocator and wasm_allocator refer to the same instance.

[fengb]

I put wasmtime in build.zig because it was slightly easier to slap in the CLI args than the alternative (wasmtime test.zig vs wasmer run test.zig).

[syrusakbary]

I put wasmtime in build.zig because it was slightly easier to slap in the CLI args than the alternative (wasmtime test.zig vs wasmer run test.zig).

We are thinking on enabling wasmer test.zig soon, so hopefully that's will be not an issue and we can use Wasmer here! :)

[syrusakbary]

I'm curious... have you tried this and it didn't worked? @fengb

 32 => return Executor{ .wasi = "wasmer run" },

[fengb]

Zig build args are generated separately --test-cmd wasmer --test-cmd run so I'd have to update the plumbing to support multiple args.

[syrusakbary]

That make sense! Thanks for the info.

To support this use case, we are working now on allowing to pass a file as first argument without being explicit with run (so you can do wasmer myfile.wasm).
I'll post an update here once it's ready to be used (which should be very soon!)

[syrusakbary]

We just added support for running wasm files directly without the run argument.
wasmerio/wasmer#990

We will publish a release soon :)

[syrusakbary]

@fengb we just released Wasmer 0.11. With it, you can run wasmer myfile.wasm directly.
So everything should be good to go to use wasmer in this PR :)

Thanks for your feedback, without it we wouldn't have improve the Wasmer CLI to make it a bit easier to use!

[andrewrk]

@syrusakbary thanks for your help! Another question for you if you don't mind. We run CI tests in the following environments:

• x86_64 Microsoft Windows 10
• x86_64 macOS 10.14
• x86_64 Ubuntu 18.04
• x86_64 and aarch64 Alpine Linux (edge from 1 month ago)
• x86_64 FreeBSD 12

Can you advise on the best way to obtain Wasmer 0.11 in these environments (or at least a subset)? I'm guessing it won't be in, for example, apt-get for Ubuntu 18.04.

[syrusakbary]

x86_64 Microsoft Windows 10

I can provide a powershell script if needed, otherwise just install Wasmer from here: https://github.com/wasmerio/wasmer/releases/download/0.11.0/wasmer-windows.exe

x86_64 macOS 10.14

curl https://get.wasmer.io -sSfL | sh

x86_64 Ubuntu 18.04

curl https://get.wasmer.io -sSfL | sh

x86_64 and aarch64 Alpine Linux (edge from 1 month ago)

We haven't tested on Alpine, but this should work in both architectures (x86_64 and aarch64) (let me know if it doesn't and we will fix it!)

curl https://get.wasmer.io -sSfL | sh

x86_64 FreeBSD 12

I think we don't currently support FreeBSD, but hopefully should not very hard to add.
Let me know if that's a requirement for you and we will prioritize it.

[andrewrk]

@syrusakbary thanks for the info! I made a follow-up issue for this here: #3775