build.rs

//! The logic that gets executed before building the binary and tests.
//! We use it to auto-generate the Wasm spectests for each of the
//! available compilers.
//!
//! Please try to keep this file as clean as possible.

use std::env;
use std::fs;
use std::path::PathBuf;
use std::process::Command;
use test_generator::{
    build_ignores_from_textfile, test_directory, test_directory_module, wast_processor,
    with_backends, with_test_module, Testsuite,
};

fn is_truthy_env(name: &str) -> bool {
    env::var(name).map(|n| n == "1").unwrap_or_default()
}

fn main() -> anyhow::Result<()> {
    println!("cargo:rerun-if-changed=build.rs");
    println!("cargo:rerun-if-changed=tests/ignores.txt");

    let out_dir = PathBuf::from(
        env::var_os("OUT_DIR").expect("The OUT_DIR environment variable must be set"),
    );
    let ignores = build_ignores_from_textfile("tests/ignores.txt".into())?;

    // Spectests test generation
    let mut spectests = Testsuite {
        buffer: String::new(),
        path: vec![],
        ignores: ignores.clone(),
    };

    let backends = vec!["singlepass", "cranelift", "llvm"];
    with_backends(&mut spectests, &backends, |mut spectests| {
        with_test_module(&mut spectests, "spec", |spectests| {
            let _spec_tests = test_directory(spectests, "tests/wast/spec", wast_processor)?;
            test_directory_module(
                spectests,
                "tests/wast/spec/proposals/multi-value",
                wast_processor,
            )?;
            // test_directory_module(spectests, "tests/wast/spec/proposals/bulk-memory-operations", wast_processor)?;
            Ok(())
        })?;
        with_test_module(&mut spectests, "wasmer", |spectests| {
            let _spec_tests = test_directory(spectests, "tests/wast/wasmer", wast_processor)?;
            Ok(())
        })?;
        Ok(())
    })?;

    let spectests_output = out_dir.join("generated_spectests.rs");
    fs::write(&spectests_output, spectests.buffer)?;

    // Write out our auto-generated tests and opportunistically format them with
    // `rustfmt` if it's installed.
    // Note: We need drop because we don't want to run `unwrap` or `expect` as
    // the command might fail, but we don't care about it's result.
    drop(Command::new("rustfmt").arg(&spectests_output).status());

    Ok(())
}