swc/crates/swc_ecma_minifier/examples/perf.rs
2021-11-10 19:00:54 +09:00

80 lines
2.1 KiB
Rust

extern crate swc_node_base;
use std::{env::args, path::Path};
use swc_common::{input::SourceFileInput, sync::Lrc, Mark, SourceMap};
use swc_ecma_codegen::text_writer::JsWriter;
use swc_ecma_minifier::{
optimize,
option::{ExtraOptions, MinifyOptions},
};
use swc_ecma_parser::{lexer::Lexer, Parser};
use swc_ecma_transforms::{fixer, resolver_with_mark};
use swc_ecma_visit::FoldWith;
fn main() {
let file = args().nth(1).expect("should provide a path to file");
eprintln!("File: {}", file);
testing::run_test2(false, |cm, handler| {
let fm = cm.load_file(Path::new(&file)).expect("failed to load file");
let top_level_mark = Mark::fresh(Mark::root());
let lexer = Lexer::new(
Default::default(),
Default::default(),
SourceFileInput::from(&*fm),
None,
);
let mut parser = Parser::new_from(lexer);
let program = parser
.parse_module()
.map_err(|err| {
err.into_diagnostic(&handler).emit();
})
.map(|module| module.fold_with(&mut resolver_with_mark(top_level_mark)))
.unwrap();
let output = optimize(
program,
cm.clone(),
None,
None,
&MinifyOptions {
compress: Some(Default::default()),
mangle: Some(Default::default()),
..Default::default()
},
&ExtraOptions { top_level_mark },
);
let output = output.fold_with(&mut fixer(None));
print(cm.clone(), &[output], true);
Ok(())
})
.unwrap();
}
fn print<N: swc_ecma_codegen::Node>(cm: Lrc<SourceMap>, nodes: &[N], minify: bool) -> String {
let mut buf = vec![];
{
let mut emitter = swc_ecma_codegen::Emitter {
cfg: swc_ecma_codegen::Config { minify },
cm: cm.clone(),
comments: None,
wr: Box::new(JsWriter::new(cm.clone(), "\n", &mut buf, None)),
};
for n in nodes {
n.emit_with(&mut emitter).unwrap();
}
}
String::from_utf8(buf).unwrap()
}