feat(cli): Deno.emit supports bundling as IIFE (denoland#9291)

Closes denoland#9204

cli/dts/lib.deno.unstable.d.ts

@@ -498,8 +498,10 @@ declare namespace Deno {
 
  interface EmitOptions {
  /** Indicate that the source code should be emitted to a single file
- * JavaScript bundle that is an ES module (`"esm"`). */
- bundle?: "esm";
+ * JavaScript bundle that is a single ES module (`"esm"`) or a single file
+ * self contained script we executes in an immediately invoked function
+ * when loaded (`"iife"`). */
+ bundle?: "esm" | "iife";
  /** If `true` then the sources will be typed checked, returning any
  * diagnostic errors in the result. If `false` type checking will be
  * skipped. Defaults to `true`.

cli/module_graph.rs

@@ -614,8 +614,10 @@ pub enum BundleType {
  /// Return the emitted contents of the program as a single "flattened" ES
  /// module.
  Esm,
- // TODO(@kitsonk) once available in swc
- // Iife,
+ /// Return the emitted contents of the program as a single script that
+ /// executes the program using an immediately invoked function execution
+ /// (IIFE).
+ Iife,
  /// Do not bundle the emit, instead returning each of the modules that are
  /// part of the program as individual files.
  None,
@@ -780,7 +782,8 @@ impl Graph {
  let maybe_ignored_options =
  ts_config.merge_tsconfig(options.maybe_config_path)?;
 
- let s = self.emit_bundle(&root_specifier, &ts_config.into())?;
+ let s =
+ self.emit_bundle(&root_specifier, &ts_config.into(), &BundleType::Esm)?;
  let stats = Stats(vec![
  ("Files".to_string(), self.modules.len() as u32),
  ("Total time".to_string(), start.elapsed().as_millis() as u32),
@@ -951,7 +954,7 @@ impl Graph {
  "target": "esnext",
  }));
  let opts = match options.bundle_type {
- BundleType::Esm => json!({
+ BundleType::Esm | BundleType::Iife => json!({
  "noEmit": true,
  }),
  BundleType::None => json!({
@@ -992,7 +995,7 @@ impl Graph {
 
  let graph = graph.lock().unwrap();
  match options.bundle_type {
- BundleType::Esm => {
+ BundleType::Esm | BundleType::Iife => {
  assert!(
  response.emitted_files.is_empty(),
  "No files should have been emitted from tsc."
@@ -1003,7 +1006,11 @@ impl Graph {
  "Only a single root module supported."
  );
  let specifier = &graph.roots[0];
- let s = graph.emit_bundle(specifier, &config.into())?;
+ let s = graph.emit_bundle(
+ specifier,
+ &config.into(),
+ &options.bundle_type,
+ )?;
  emitted_files.insert("deno:https:///bundle.js".to_string(), s);
  }
  BundleType::None => {
@@ -1044,14 +1051,18 @@ impl Graph {
  let start = Instant::now();
  let mut emit_count = 0_u32;
  match options.bundle_type {
- BundleType::Esm => {
+ BundleType::Esm | BundleType::Iife => {
  assert_eq!(
  self.roots.len(),
  1,
  "Only a single root module supported."
  );
  let specifier = &self.roots[0];
- let s = self.emit_bundle(specifier, &config.into())?;
+ let s = self.emit_bundle(
+ specifier,
+ &config.into(),
+ &options.bundle_type,
+ )?;
  emit_count += 1;
  emitted_files.insert("deno:https:///bundle.js".to_string(), s);
  }
@@ -1104,19 +1115,28 @@ impl Graph {
  &self,
  specifier: &ModuleSpecifier,
  emit_options: &ast::EmitOptions,
+ bundle_type: &BundleType,
  ) -> Result<String, AnyError> {
  let cm = Rc::new(swc_common::SourceMap::new(
  swc_common::FilePathMapping::empty(),
  ));
  let globals = swc_common::Globals::new();
  let loader = BundleLoader::new(self, emit_options, &globals, cm.clone());
  let hook = Box::new(BundleHook);
+ let module = match bundle_type {
+ BundleType::Esm => swc_bundler::ModuleType::Es,
+ BundleType::Iife => swc_bundler::ModuleType::Iife,
+ _ => unreachable!("invalid bundle type"),
+ };
  let bundler = swc_bundler::Bundler::new(
  &globals,
  cm.clone(),
  loader,
  self,
- swc_bundler::Config::default(),
+ swc_bundler::Config {
+ module,
+ ..Default::default()
+ },
  hook,
  );
  let mut entries = HashMap::new();

cli/ops/runtime_compiler.rs

@@ -35,6 +35,8 @@ pub fn init(rt: &mut deno_core::JsRuntime) {
 enum RuntimeBundleType {
  #[serde(rename = "esm")]
  Esm,
+ #[serde(rename = "iife")]
+ Iife,
 }
 
 #[derive(Debug, Deserialize)]
@@ -106,7 +108,8 @@ async fn op_emit(
  })?;
  let bundle_type = match args.bundle {
  Some(RuntimeBundleType::Esm) => BundleType::Esm,
- _ => BundleType::None,
+ Some(RuntimeBundleType::Iife) => BundleType::Iife,
+ None => BundleType::None,
  };
  let graph = builder.get_graph();
  let debug = program_state.flags.log_level == Some(log::Level::Debug);

cli/tests/compiler_api_test.ts

@@ -319,3 +319,22 @@ Deno.test({
  assert(typeof files[`${specifier}.js.map`] === "string");
  },
 });
+
+Deno.test({
+ name: `Deno.emit() - bundle supports iife`,
+ async fn() {
+ const { diagnostics, files } = await Deno.emit("/a.ts", {
+ bundle: "iife",
+ sources: {
+ "/a.ts": `import { b } from "./b.ts";
+ console.log(b);`,
+ "/b.ts": `export const b = "b";`,
+ },
+ });
+ assert(diagnostics);
+ assertEquals(diagnostics.length, 0);
+ assertEquals(Object.keys(files).length, 1);
+ assert(files["deno:https:///bundle.js"].startsWith("(function() {\n"));
+ assert(files["deno:https:///bundle.js"].endsWith("})();\n"));
+ },
+});