swc/crates/swc_estree_compat/benches/babelify.rs

use std::{io::stderr, sync::Arc};

use criterion::{black_box, criterion_group, criterion_main, Bencher, Criterion};
use swc::config::IsModule;
use swc_common::{
    errors::Handler, FileName, FilePathMapping, Mark, SourceFile, SourceMap, GLOBALS,
};
use swc_ecma_ast::{EsVersion, Program};
use swc_ecma_parser::Syntax;
use swc_ecma_transforms::{compat::es2020, resolver, typescript};
use swc_ecma_visit::FoldWith;
use swc_estree_compat::babelify::{Babelify, Context};

static SOURCE: &str = include_str!("assets/AjaxObservable.ts");

fn mk() -> swc::Compiler {
    let cm = Arc::new(SourceMap::new(FilePathMapping::empty()));

    swc::Compiler::new(cm)
}

fn parse(c: &swc::Compiler, src: &str) -> (Arc<SourceFile>, Program) {
    let fm = c.cm.new_source_file(
        FileName::Real("rxjs/src/internal/observable/dom/AjaxObservable.ts".into()),
        src.to_string(),
    );

    let handler = Handler::with_emitter_writer(Box::new(stderr()), Some(c.cm.clone()));

    let comments = c.comments().clone();
    let module = c
        .parse_js(
            fm.clone(),
            &handler,
            EsVersion::Es5,
            Syntax::Typescript(Default::default()),
            IsModule::Bool(true),
            Some(&comments),
        )
        .unwrap();

    (fm, module)
}

fn babelify_only(b: &mut Bencher) {
    GLOBALS.set(&Default::default(), || {
        let c = mk();
        let (fm, module) = parse(&c, SOURCE);
        let handler = Handler::with_emitter_writer(Box::new(stderr()), Some(c.cm.clone()));

        let module = c.run_transform(&handler, false, || {
            let unresolved_mark = Mark::new();
            let top_level_mark = Mark::new();

            module
                .fold_with(&mut resolver(unresolved_mark, top_level_mark, true))
                .fold_with(&mut typescript::strip(top_level_mark))
                .fold_with(&mut es2020(Default::default(), unresolved_mark))
        });

        b.iter(|| {
            let program = module.clone();
            let ctx = Context {
                fm: fm.clone(),
                cm: c.cm.clone(),
                comments: c.comments().clone(),
            };

            let babel_ast = program.babelify(&ctx);
            black_box(babel_ast)
        });
    })
}

fn parse_and_babelify(b: &mut Bencher, _name: &str, src: &str) {
    GLOBALS.set(&Default::default(), || {
        let c = mk();

        b.iter(|| {
            let (fm, program) = parse(&c, src);
            let ctx = Context {
                fm,
                cm: c.cm.clone(),
                comments: c.comments().clone(),
            };

            let babel_ast = program.babelify(&ctx);
            black_box(babel_ast);
        });
    })
}

fn bench_cases(c: &mut Criterion) {
    c.bench_function("babelify-only", babelify_only);

    /// https://esprima.org/test/compare.html
    macro_rules! src_to_babel_ast {
        ($name:ident, $src:expr) => {
            c.bench_function(stringify!($name), |b| {
                parse_and_babelify(b, stringify!($name), $src)
            });
        };
    }

    src_to_babel_ast!(
        parse_and_babelify_angular,
        include_str!("../../swc_ecma_parser/benches/files/angular-1.2.5.js")
    );

    src_to_babel_ast!(
        parse_and_babelify_backbone,
        include_str!("../../swc_ecma_parser/benches/files/backbone-1.1.0.js")
    );

    src_to_babel_ast!(
        parse_and_babelify_jquery,
        include_str!("../../swc_ecma_parser/benches/files/jquery-1.9.1.js")
    );

    src_to_babel_ast!(
        parse_and_babelify_jquery_mobile,
        include_str!("../../swc_ecma_parser/benches/files/jquery.mobile-1.4.2.js")
    );

    src_to_babel_ast!(
        parse_and_babelify_mootools,
        include_str!("../../swc_ecma_parser/benches/files/mootools-1.4.5.js")
    );

    src_to_babel_ast!(
        parse_and_babelify_underscore,
        include_str!("../../swc_ecma_parser/benches/files/underscore-1.5.2.js")
    );

    src_to_babel_ast!(
        parse_and_babelify_yui,
        include_str!("../../swc_ecma_parser/benches/files/yui-3.12.0.js")
    );
}

criterion_group!(benches, bench_cases);
criterion_main!(benches);