Testing

cargo test runs everything:

Suite	What it checks
`tests/golden.rs`	every program in `tests/run` and `examples/` compiles, prints its `// expect:` lines and exits with its `// exit:` code; every file in `tests/fail` fails with its `// error:` texts
`tests/diag.rs`	diagnostic snapshots: each `.volt` file in `tests/diag` must print exactly the `.stderr` file of the same name
`tests/selfhost.rs`	stage1 checks its own sources; the reviewed C output in `tests/cgen`; a release voltc built by itself runs `tests/run` on both backends and bare metal under qemu; the runtime and std compile for other systems; and the bootstrap
`tests/abi.rs`	the LLVM backend’s calling conventions give each export fn in `tests/abi/sigs.volt` the signature clang gives the same C, for each host; on aarch64, C and Volt call each other under qemu
`tests/fuzz.rs`	broken variants of the test programs get diagnostics, never a crash or a hang; generated programs print the same through both backends, debug and release
`tests/embed.rs`	Volt embedded in C, Python and Rust programs through `voltc/embed`’s `libvoltvm.so`
`tests/bolt.rs`	bolt end to end: packages, workspaces, git dependencies, features, build files
`tests/interop.rs`	Volt with C, C++ (and its standard library), Rust, Zig, Python, Node, C#, Java, Go, Lua, Dart, Swift, Kotlin and Ruby, both ways, by hand and through bolt; and every example in `examples/interop` (its `run.sh` against its `expected.txt`)
`tests/lsp.rs`	a scripted session with `voltc lsp`
`tests/docs.rs`	every code block on this site compiles (and prints what it shows); the C and LLVM IR on the front page are what voltc writes; the std reference is current
`tests/site.rs`	the site’s generator (`site/gen`, in Volt) builds every page with the theme’s structure, and a link that goes nowhere fails the build
`tests/headers.rs`	every source file opens with a comment saying what it is
`tests/cc_env.rs`	`$CC` with a wrapper command or flags
`tests/bench.rs`	ignored by default: Volt against C, C++, Rust and Zig on the programs in `bench/` (see Benchmarks)

Golden files take directives in comments:

use std::io;
// flags: --release

fn main() -> i32 {
    std::println("hi");
    return 3;
}
// expect: hi
// exit: 3

Each // expect-stderr: line has to appear in what the program prints to stderr, and // exit: N|M takes either code (a trap is SIGILL on x86-64, SIGTRAP on arm64).

editors/vscode has its own tests (npm test: the grammar, and where the extension looks for voltc and bolt).