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#[cfg(feature = "js-esbuild")]
use {aho_corasick::AhoCorasick, crossbeam::sync::WaitGroup, esbuild_rs::TransformOptions};
#[cfg(feature = "js-esbuild")]
// TODO The use of WG is ugly and we don't want to be multi-threaded; wait for Rust port esbuild-transform-rs.
// `tag_to_escape` must be case insensitive if provided.
pub fn minify_using_esbuild(
out: &mut Vec<u8>,
code: &[u8],
transform_options: &TransformOptions,
tag_to_escape: Option<&'static AhoCorasick>,
) {
let wg = WaitGroup::new();
unsafe {
let wg = wg.clone();
esbuild_rs::transform_direct_unmanaged(code, transform_options, move |result| {
let min_code = result.code.as_str().trim().as_bytes();
match tag_to_escape {
None => out.extend_from_slice(min_code),
// TODO (JS) Handle other forms:
// 1 < /script/.exec(a).length
// ` ${` ${a</script/} `} `
// // </script>
// /* </script>
// Considerations:
// - Need to parse strings (e.g. "", '', ``) so syntax within strings aren't mistakenly interpreted as code.
// - Need to be able to parse regex literals to determine string delimiters aren't actually characters in the regex.
// - Determining whether a slash is division or regex requires a full-blown JS parser to handle all cases (this is a well-known JS parsing problem).
// - `/</script` or `/</ script` are not valid JS so don't need to be handled.
// TODO (CSS) Are there other places that can have unintentional closing tags?
Some(tag_to_escape) => {
tag_to_escape.replace_all_with_bytes(min_code, out, |_, orig, dst| {
dst.extend(b"<\\/");
// Keep original case.
dst.extend(&orig[2..]);
true
})
}
}
drop(wg);
});
};
wg.wait();
}