WASI-based runners don't pass arguments to the WebAssembly instance correctly

[Michael-F-Bryan]

Describe the bug

@ayys and I found a bug in the way command-line arguments are passed to the WebAssembly instance. It looks like some arguments are being passed in twice, which messes up things for the program being executed.

$ wasmer --version --verbose
wasmer 3.1.0 (0e336 2022-12-12)
binary: wasmer-cli
commit-hash: 0e3369a9d906513eb90cfac2e3160d8c2ded4247
commit-date: 2022-12-12
host: aarch64-apple-darwin
compiler: singlepass,cranelift
$ rustc --version --verbose
rustc 1.65.0 (897e37553 2022-11-02)
binary: rustc
commit-hash: 897e37553bba8b42751c67658967889d11ecd120
commit-date: 2022-11-02
host: aarch64-apple-darwin
release: 1.65.0
LLVM version: 15.0.0

Steps to reproduce

$ wasmer run-unstable saghul/quickjs --command=qjs -- --eval 'console.log(scriptArgs)' hello world "hello world"
hello,world,hello world,--eval,console.log(scriptArgs),hello,world,hello world

The output should be just --eval,console.log(scriptArgs),hello,world,hello world.

It seems like command-line arguments are being sent through twice, but for whatever reason anything with an argument gets skipped.

Additional context

This seems to be an issue in the way arguments are constructed for a WASI-based runner. We tried running quickjs.wasm directly and it behaved correctly.

A good place to start looking would be here:

wasmer/lib/wasi/src/runners/wasi_common.rs

Lines 70 to 76 in 8a343d0

	fn populate_args(&self, wasi: &WasiAnnotation, builder: &mut WasiEnvBuilder) {
	if let Some(main_args) = &wasi.main_args {
	builder.add_args(main_args);
	}
	builder.add_args(&self.args);
	}