add measuring of the rewrite() function

rewriter/Cargo.toml

@@ -25,6 +25,7 @@ panic = "abort"
 [dependencies]
 console_error_panic_hook = "0.1.7"
 getrandom = { version = "0.2.15", features = ["js"] }
+instant = { version = "0.1.13", features = ["wasm-bindgen"] }
 js-sys = "0.3.69"
 obfstr = "0.4.3"
 oxc_allocator = "0.32.0"

rewriter/src/lib.rs

@@ -1,9 +1,10 @@
 pub mod error;
 pub mod rewrite;
 
-use std::{panic, str::FromStr, sync::Arc};
+use std::{panic, str::FromStr, sync::Arc, time::Duration};
 
 use error::{Result, RewriterError};
+use instant::Instant;
 use js_sys::{Function, Object, Reflect};
 use oxc_diagnostics::{NamedSource, OxcDiagnostic};
 use rewrite::{rewrite, Config, EncodeFn};
@@ -12,7 +13,7 @@ use wasm_bindgen::prelude::*;
 
 #[wasm_bindgen(typescript_custom_section)]
 const REWRITER_OUTPUT: &'static str = r#"
-type RewriterOutput = { js: Uint8Array, errors: string[] };
+type RewriterOutput = { js: Uint8Array, errors: string[], duration: bigint };
 "#;
 
 #[wasm_bindgen]
@@ -110,10 +111,15 @@ fn drmcheck() -> bool {
 	return vec![obfstr!("http://localhost:1337")].contains(&true_origin.as_str());
 }
 
+fn duration_to_millis_f64(duration: Duration) -> f64 {
+	(duration.as_secs() as f64) * 1_000f64 + (duration.subsec_nanos() as f64) / 1_000_000f64
+}
+
 fn create_rewriter_output(
 	out: (Vec<u8>, Vec<OxcDiagnostic>),
 	url: String,
 	src: String,
+	duration: Duration,
 ) -> Result<RewriterOutput> {
 	let src = Arc::new(NamedSource::new(url, src).with_language("javascript"));
 	let errs: Vec<_> = out
@@ -123,8 +129,9 @@ fn create_rewriter_output(
 		.collect();
 
 	let obj = Object::new();
-	set_obj(&obj, "js", &JsValue::from(out.0))?;
-	set_obj(&obj, "errors", &JsValue::from(errs))?;
+	set_obj(&obj, "js", &out.0.into())?;
+	set_obj(&obj, "errors", &errs.into())?;
+	set_obj(&obj, "duration", &duration_to_millis_f64(duration).into())?;
 
 	Ok(RewriterOutput::from(JsValue::from(obj)))
 }
@@ -141,11 +148,11 @@ pub fn rewrite_js(
 		return Vec::new();
 	}
 
-	create_rewriter_output(
-		rewrite(js, Url::from_str(url)?, get_config(scramjet, url)?)?,
-		script_url,
-		js.to_string(),
-	)
+	let before = Instant::now();
+	let out = rewrite(js, Url::from_str(url)?, get_config(scramjet, url)?)?;
+	let after = Instant::now();
+
+	create_rewriter_output(out, script_url, js.to_string(), after - before)
 }
 
 #[wasm_bindgen]
@@ -163,9 +170,9 @@ pub fn rewrite_js_from_arraybuffer(
 	// we know that this is a valid utf-8 string
 	let js = unsafe { std::str::from_utf8_unchecked(js) };
 
-	create_rewriter_output(
-		rewrite(js, Url::from_str(url)?, get_config(scramjet, url)?)?,
-		script_url,
-		js.to_string(),
-	)
+	let before = Instant::now();
+	let out = rewrite(js, Url::from_str(url)?, get_config(scramjet, url)?)?;
+	let after = Instant::now();
+
+	create_rewriter_output(out, script_url, js.to_string(), after - before)
 }

src/shared/rewriters/js.ts

@@ -6,6 +6,7 @@ import {
 	initSync,
 	rewrite_js,
 	rewrite_js_from_arraybuffer,
+	RewriterOutput,
 } from "../../../rewriter/out/rewriter.js";
 import { $scramjet, flagEnabled } from "../../scramjet";
 
@@ -19,13 +20,51 @@ init();
 
 Error.stackTraceLimit = 50;
 
-function print_errors(errors: string[]) {
+const decoder = new TextDecoder();
+
+function rewriteJsWrapper(
+	input: string | ArrayBuffer,
+	meta: URLMeta
+): string | ArrayBuffer {
+	let out: RewriterOutput;
+	if (typeof input === "string") {
+		out = rewrite_js(
+			input,
+			meta.base.href,
+			"PERCS_PLEASE_FILL_THIS_IN.js",
+			$scramjet
+		);
+	} else {
+		out = rewrite_js_from_arraybuffer(
+			new Uint8Array(input),
+			meta.base.href,
+			"PERCS_PLEASE_FILL_THIS_IN.js",
+			$scramjet
+		);
+	}
+	const { js, errors, duration } = out;
+
 	// TODO: maybe make this a scram flag?
 	if (true) {
 		for (const error of errors) {
 			console.error("oxc parse error", error);
 		}
 	}
+
+	// TODO: maybe make this a scram flag?
+	if (true) {
+		let timespan: string;
+		if (duration < 1n) {
+			timespan = "BLAZINGLY FAST";
+		} else if (duration < 500n) {
+			timespan = "decent speed";
+		} else {
+			timespan = "really slow";
+		}
+		console.log(`oxc rewrite was ${timespan} (${duration}ms)`);
+	}
+
+	return typeof input === "string" ? decoder.decode(js) : js;
 }
 
 export function rewriteJs(js: string | ArrayBuffer, meta: URLMeta) {
@@ -37,29 +76,7 @@ export function rewriteJs(js: string | ArrayBuffer, meta: URLMeta) {
 		return rewriteJsNaiive(text);
 	}
 
-	// const before = performance.now();
-	if (typeof js === "string") {
-		let { js: js_out, errors } = rewrite_js(
-			js,
-			meta.base.href,
-			"PERCS_PLEASE_FILL_THIS_IN.js",
-			$scramjet
-		);
-		js = new TextDecoder().decode(js_out);
-		print_errors(errors);
-	} else {
-		let { js: js_out, errors } = rewrite_js_from_arraybuffer(
-			new Uint8Array(js),
-			meta.base.href,
-			"PERCS_PLEASE_FILL_THIS_IN.js",
-			$scramjet
-		);
-		js = js_out;
-		print_errors(errors);
-	}
-	// const after = performance.now();
-
-	// dbg.debug("Rewrite took", Math.floor((after - before) * 10) / 10, "ms");
+	js = rewriteJsWrapper(js, meta);
 
 	return js;
 }