feat(binding): Create Wasm package for stripping only TypeScript (#9124)

**Description:**

This PR adds a Wasm binding which is only capable of stripping TypeScript types.


**Related issue:**

 - https://github.com/marco-ippolito/node/pull/2

.github/workflows/publish-core.yml

@@ -508,11 +508,14 @@ jobs:
       matrix:
         settings:
           - crate: "binding_core_wasm"
-            npm: "@swc/wasm"
+            npm: "@swc\\/wasm"
             target: nodejs
           - crate: "binding_core_wasm"
-            npm: "@swc/wasm-web"
+            npm: "@swc\\/wasm-web"
             target: web
+          - crate: "binding_typescript_wasm"
+            npm: "@swc\\/wasm-typescript"
+            target: no-modules
     steps:
       - uses: actions/checkout@v4
 

bindings/Cargo.lock

@@ -302,6 +302,23 @@ dependencies = [
  "wasm-bindgen",
 ]
 
+[[package]]
+name = "binding_typescript_wasm"
+version = "1.6.6"
+dependencies = [
+ "anyhow",
+ "getrandom",
+ "serde",
+ "serde-wasm-bindgen",
+ "serde_json",
+ "swc_core",
+ "swc_ecma_codegen",
+ "swc_error_reporters",
+ "tracing",
+ "wasm-bindgen",
+ "wasm-bindgen-futures",
+]
+
 [[package]]
 name = "bitflags"
 version = "1.3.2"
@@ -2653,9 +2670,9 @@ dependencies = [
 
 [[package]]
 name = "serde_json"
-version = "1.0.115"
+version = "1.0.120"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "12dc5c46daa8e9fdf4f5e71b6cf9a53f2487da0e86e55808e2d35539666497dd"
+checksum = "4e0d21c9a8cae1235ad58a00c11cb40d4b1e5c784f1ef2c537876ed6ffd8b7c5"
 dependencies = [
  "itoa",
  "ryu",
@@ -3208,6 +3225,7 @@ dependencies = [
  "swc_ecma_minifier",
  "swc_ecma_parser",
  "swc_ecma_transforms_base",
+ "swc_ecma_transforms_typescript",
  "swc_ecma_visit",
  "swc_malloc",
  "swc_node_bundler",

bindings/Cargo.toml

@@ -4,6 +4,7 @@ members = [
   "binding_core_wasm",
   "binding_minifier_node",
   "binding_minifier_wasm",
+  "binding_typescript_wasm",
   "swc_cli",
 ]
 resolver = "2"

bindings/binding_core_node/build.rs

@@ -17,7 +17,7 @@ fn main() {
     let out_dir = env::var("OUT_DIR").expect("Outdir should exist");
     let dest_path = Path::new(&out_dir).join("triple.txt");
     let mut f =
-        BufWriter::new(File::create(&dest_path).expect("Failed to create target triple text"));
+        BufWriter::new(File::create(dest_path).expect("Failed to create target triple text"));
     write!(
         f,
         "{}",

bindings/binding_minifier_node/src/minify.rs

@@ -7,8 +7,7 @@ use napi::{
 };
 use serde::Deserialize;
 use swc_compiler_base::{
-    minify_file_comments, parse_js, IdentCollector, IsModule, PrintArgs, SourceMapsConfig,
-    TransformOutput,
+    minify_file_comments, parse_js, IdentCollector, PrintArgs, SourceMapsConfig, TransformOutput,
 };
 use swc_config::config_types::BoolOr;
 use swc_core::{
@@ -23,7 +22,7 @@ use swc_core::{
             js::{JsMinifyCommentOption, JsMinifyOptions},
             option::{MinifyOptions, TopLevelOptions},
         },
-        parser::{EsConfig, Syntax},
+        parser::{EsSyntax, Syntax},
         transforms::base::{fixer::fixer, hygiene::hygiene, resolver},
         visit::{FoldWith, VisitMutWith, VisitWith},
     },
@@ -109,11 +108,30 @@ fn do_work(input: MinifyTarget, options: JsMinifyOptions) -> napi::Result<Transf
             ..Default::default()
         };
 
+        let comments = SingleThreadedComments::default();
+
+        let module = parse_js(
+            cm.clone(),
+            fm.clone(),
+            handler,
+            target,
+            Syntax::Es(EsSyntax {
+                jsx: true,
+                decorators: true,
+                decorators_before_export: true,
+                import_attributes: true,
+                ..Default::default()
+            }),
+            options.module,
+            Some(&comments),
+        )
+        .context("failed to parse input file")?;
+
         // top_level defaults to true if module is true
 
         // https://github.com/swc-project/swc/issues/2254
 
-        if options.module {
+        if module.is_module() {
             if let Some(opts) = &mut min_opts.compress {
                 if opts.top_level.is_none() {
                     opts.top_level = Some(TopLevelOptions { functions: true });
@@ -136,25 +154,6 @@ fn do_work(input: MinifyTarget, options: JsMinifyOptions) -> napi::Result<Transf
             }
         }
 
-        let comments = SingleThreadedComments::default();
-
-        let module = parse_js(
-            cm.clone(),
-            fm.clone(),
-            handler,
-            target,
-            Syntax::Es(EsConfig {
-                jsx: true,
-                decorators: true,
-                decorators_before_export: true,
-                import_attributes: true,
-                ..Default::default()
-            }),
-            IsModule::Bool(options.module),
-            Some(&comments),
-        )
-        .context("failed to parse input file")?;
-
         let source_map_names = if source_map.enabled() {
             let mut v = IdentCollector {
                 names: Default::default(),
@@ -172,7 +171,7 @@ fn do_work(input: MinifyTarget, options: JsMinifyOptions) -> napi::Result<Transf
 
         let is_mangler_enabled = min_opts.mangle.is_some();
 
-        let module = (|| {
+        let module = {
             let module = module.fold_with(&mut resolver(unresolved_mark, top_level_mark, false));
 
             let mut module = swc_core::ecma::minifier::optimize(
@@ -192,7 +191,7 @@ fn do_work(input: MinifyTarget, options: JsMinifyOptions) -> napi::Result<Transf
             }
             module.visit_mut_with(&mut fixer(Some(&comments as &dyn Comments)));
             module
-        })();
+        };
 
         let preserve_comments = options
             .format
@@ -211,7 +210,7 @@ fn do_work(input: MinifyTarget, options: JsMinifyOptions) -> napi::Result<Transf
                 inline_sources_content: options.inline_sources_content,
                 source_map,
                 source_map_names: &source_map_names,
-                orig: orig.as_ref(),
+                orig,
                 comments: Some(&comments),
                 emit_source_map_columns: options.emit_source_map_columns,
                 preamble: &options.format.preamble,

bindings/binding_minifier_wasm/scripts/build.sh

@@ -1 +0,0 @@
-wasm-pack build --debug --scope swc -t nodejs --features plugin --features getrandom/js $@

bindings/binding_minifier_wasm/scripts/build_nodejs_release.sh

@@ -1,4 +0,0 @@
-#!/bin/bash
-
-# run this script from the wasm folder ./scripts/build_nodejs_release.sh
-npx wasm-pack build --scope swc -t nodejs --features plugin

bindings/binding_minifier_wasm/scripts/build_web_release.sh

@@ -1,4 +0,0 @@
-#!/bin/bash
-
-# run this script from the wasm folder ./scripts/build_web_release.sh
-npx wasm-pack build --scope swc --features plugin

bindings/binding_minifier_wasm/scripts/test.sh

@@ -1,6 +0,0 @@
-#!/usr/bin/env bash
-
-set -eu
-
-./scripts/build.sh
-npx jest $@

bindings/binding_typescript_wasm/Cargo.toml

@@ -0,0 +1,40 @@
+[package]
+authors     = ["강동윤 <kdy1997.dev@gmail.com>"]
+description = "wasm module for swc"
+edition     = "2021"
+license     = "Apache-2.0"
+name        = "binding_typescript_wasm"
+publish     = false
+repository  = "https://github.com/swc-project/swc.git"
+version     = "1.6.6"
+
+[lib]
+bench      = false
+crate-type = ["cdylib"]
+
+[features]
+default = ["swc_v1"]
+swc_v1  = []
+swc_v2  = []
+
+[dependencies]
+anyhow = "1.0.66"
+getrandom = { version = "0.2.10", features = ["js"] }
+serde = { version = "1", features = ["derive"] }
+serde-wasm-bindgen = "0.4.5"
+serde_json = "1.0.120"
+swc_core = { version = "0.95.10", features = [
+  "ecma_ast_serde",
+  "ecma_codegen",
+  "ecma_transforms",
+  "ecma_transforms_typescript",
+  "ecma_visit",
+] }
+swc_ecma_codegen = { version = "0.151.1", features = ["serde-impl"] }
+swc_error_reporters = "0.18.0"
+tracing = { version = "0.1.37", features = ["max_level_off"] }
+wasm-bindgen = { version = "0.2.82", features = ["enable-interning"] }
+wasm-bindgen-futures = { version = "0.4.41" }
+
+[package.metadata.wasm-pack.profile.release]
+wasm-opt = false

bindings/binding_typescript_wasm/package.json

@@ -0,0 +1,5 @@
+{
+    "devDependencies": {
+        "jest": "^25.1.0"
+    }
+}

bindings/binding_typescript_wasm/src/lib.rs

@@ -0,0 +1,227 @@
+use anyhow::{Context, Error};
+use serde::{Deserialize, Serialize};
+use swc_core::{
+    base::{config::ErrorFormat, HandlerOpts},
+    common::{
+        comments::SingleThreadedComments, errors::ColorConfig, source_map::SourceMapGenConfig,
+        sync::Lrc, FileName, Mark, SourceMap, GLOBALS,
+    },
+    ecma::{
+        ast::{EsVersion, Program},
+        codegen::text_writer::JsWriter,
+        parser::{
+            parse_file_as_module, parse_file_as_program, parse_file_as_script, Syntax, TsSyntax,
+        },
+        transforms::base::{
+            fixer::fixer,
+            helpers::{inject_helpers, Helpers, HELPERS},
+            hygiene::hygiene,
+            resolver,
+        },
+        visit::VisitMutWith,
+    },
+};
+use swc_error_reporters::handler::try_with_handler;
+use wasm_bindgen::prelude::*;
+use wasm_bindgen_futures::{
+    future_to_promise,
+    js_sys::{JsString, Promise},
+};
+
+/// Custom interface definitions for the @swc/wasm's public interface instead of
+/// auto generated one, which is not reflecting most of types in detail.
+#[wasm_bindgen(typescript_custom_section)]
+const INTERFACE_DEFINITIONS: &'static str = r#"
+export function transform(src: string, opts?: Options): Promise<TransformOutput>;
+export function transformSync(src: string, opts?: Options): TransformOutput;
+"#;
+
+#[derive(Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct Options {
+    #[serde(default)]
+    pub module: Option<bool>,
+    #[serde(default)]
+    pub filename: Option<String>,
+
+    #[serde(default)]
+    pub parser: TsSyntax,
+
+    #[serde(default)]
+    pub external_helpers: bool,
+
+    #[serde(default)]
+    pub source_maps: bool,
+
+    #[serde(default)]
+    pub transform: swc_core::ecma::transforms::typescript::Config,
+
+    #[serde(default)]
+    pub codegen: swc_core::ecma::codegen::Config,
+}
+
+#[derive(Serialize)]
+pub struct TransformOutput {
+    code: String,
+    map: Option<String>,
+}
+
+#[wasm_bindgen]
+pub fn transform(input: JsString, options: JsValue) -> Promise {
+    future_to_promise(async move { transform_sync(input, options) })
+}
+
+#[wasm_bindgen]
+pub fn transform_sync(input: JsString, options: JsValue) -> Result<JsValue, JsValue> {
+    let options: Options = serde_wasm_bindgen::from_value(options)?;
+
+    let input = input.as_string().unwrap();
+
+    let result = GLOBALS
+        .set(&Default::default(), || operate(input, options))
+        .map_err(|err| convert_err(err, None))?;
+
+    Ok(serde_wasm_bindgen::to_value(&result)?)
+}
+
+fn operate(input: String, options: Options) -> Result<TransformOutput, Error> {
+    let cm = Lrc::new(SourceMap::default());
+
+    try_with_handler(
+        cm.clone(),
+        HandlerOpts {
+            color: ColorConfig::Never,
+            skip_filename: true,
+        },
+        |handler| {
+            let filename = options
+                .filename
+                .map_or(FileName::Anon, |f| FileName::Real(f.into()));
+
+            let fm = cm.new_source_file(filename, input);
+
+            let syntax = Syntax::Typescript(options.parser);
+            let target = EsVersion::latest();
+
+            let comments = SingleThreadedComments::default();
+            let mut errors = vec![];
+
+            let program = match options.module {
+                Some(true) => {
+                    parse_file_as_module(&fm, syntax, target, Some(&comments), &mut errors)
+                        .map(Program::Module)
+                }
+                Some(false) => {
+                    parse_file_as_script(&fm, syntax, target, Some(&comments), &mut errors)
+                        .map(Program::Script)
+                }
+                None => parse_file_as_program(&fm, syntax, target, Some(&comments), &mut errors),
+            };
+
+            let mut program = match program {
+                Ok(program) => program,
+                Err(err) => {
+                    err.into_diagnostic(handler).emit();
+
+                    for e in errors {
+                        e.into_diagnostic(handler).emit();
+                    }
+
+                    return Err(anyhow::anyhow!("failed to parse"));
+                }
+            };
+
+            if !errors.is_empty() {
+                for e in errors {
+                    e.into_diagnostic(handler).emit();
+                }
+
+                return Err(anyhow::anyhow!("failed to parse"));
+            }
+
+            let unresolved_mark = Mark::new();
+            let top_level_mark = Mark::new();
+
+            HELPERS.set(&Helpers::new(options.external_helpers), || {
+                // Apply resolver
+
+                program.visit_mut_with(&mut resolver(unresolved_mark, top_level_mark, true));
+
+                // Strip typescript types
+
+                program.visit_mut_with(&mut swc_core::ecma::transforms::typescript::typescript(
+                    options.transform,
+                    top_level_mark,
+                ));
+
+                // Apply external helpers
+
+                program.visit_mut_with(&mut inject_helpers(unresolved_mark));
+
+                // Apply hygiene
+
+                program.visit_mut_with(&mut hygiene());
+
+                // Apply fixer
+
+                program.visit_mut_with(&mut fixer(Some(&comments)));
+            });
+
+            // Generate code
+
+            let mut buf = vec![];
+            let mut src_map_buf = if options.source_maps {
+                Some(vec![])
+            } else {
+                None
+            };
+
+            {
+                let wr = JsWriter::new(cm.clone(), "\n", &mut buf, src_map_buf.as_mut());
+                let mut emitter = swc_core::ecma::codegen::Emitter {
+                    cfg: options.codegen,
+                    cm: cm.clone(),
+                    comments: Some(&comments),
+                    wr,
+                };
+
+                emitter.emit_program(&program).unwrap();
+            }
+
+            let code = String::from_utf8(buf).context("generated code is not utf-8")?;
+
+            let map = if let Some(src_map_buf) = src_map_buf {
+                let mut wr = vec![];
+                let map = cm.build_source_map_with_config(&src_map_buf, None, TsSourceMapGenConfig);
+
+                map.to_writer(&mut wr)
+                    .context("failed to write source map")?;
+
+                let map = String::from_utf8(wr).context("source map is not utf-8")?;
+                Some(map)
+            } else {
+                None
+            };
+
+            Ok(TransformOutput { code, map })
+        },
+    )
+}
+
+pub fn convert_err(
+    err: Error,
+    error_format: Option<ErrorFormat>,
+) -> wasm_bindgen::prelude::JsValue {
+    error_format
+        .unwrap_or(ErrorFormat::Normal)
+        .format(&err)
+        .into()
+}
+
+struct TsSourceMapGenConfig;
+
+impl SourceMapGenConfig for TsSourceMapGenConfig {
+    fn file_name_to_source(&self, f: &FileName) -> String {
+        f.to_string()
+    }
+}

scripts/publish.sh

@@ -19,7 +19,7 @@ echo "Publishing $version with swc_core $swc_core_version"
 # Update version
 (cd ./packages/core && npm version "$version" --no-git-tag-version --allow-same-version || true)
 (cd ./packages/minifier && npm version "$version" --no-git-tag-version --allow-same-version || true)
-(cd ./bindings && cargo set-version $version -p binding_core_wasm -p binding_minifier_wasm)
+(cd ./bindings && cargo set-version $version -p binding_core_wasm -p binding_minifier_wasm -p binding_typescript_wasm)
 (cd ./bindings && cargo set-version --bump patch -p swc_cli)
 
 

yarn.lock

@@ -6323,6 +6323,14 @@ __metadata:
   languageName: unknown
   linkType: soft
 
+"binding_typescript_wasm-2142ce@workspace:bindings/binding_typescript_wasm":
+  version: 0.0.0-use.local
+  resolution: "binding_typescript_wasm-2142ce@workspace:bindings/binding_typescript_wasm"
+  dependencies:
+    jest: "npm:^25.1.0"
+  languageName: unknown
+  linkType: soft
+
 "bindings@npm:^1.5.0":
   version: 1.5.0
   resolution: "bindings@npm:1.5.0"