feat: supports compiling TS module files

packages/svelte/src/compiler/index.js

@@ -52,7 +52,7 @@ export function compile(source, options) {
 }
 
 /**
- * `compileModule` takes your JavaScript source code containing runes, and turns it into a JavaScript module.
+ * `compileModule` takes your JavaScript/TypeScript source code containing runes, and turns it into a JavaScript module.
  *
  * @param {string} source The component source code
  * @param {ModuleCompileOptions} options
@@ -64,7 +64,7 @@ export function compileModule(source, options) {
 	const validated = validate_module_options(options, '');
 	state.reset(source, validated);
 
-	const analysis = analyze_module(parse_acorn(source, false), validated);
+	const analysis = analyze_module(parse_acorn(source, options.typeScript ?? false), validated);
 	return transform_module(analysis, source, validated);
 }
 

packages/svelte/src/compiler/types/index.d.ts

@@ -57,7 +57,7 @@ export interface OptimizeOptions {
 	hydrate?: boolean;
 }
 
-export interface CompileOptions extends ModuleCompileOptions {
+export interface CompileOptions extends Omit<ModuleCompileOptions, 'typeScript'> {
 	/**
 	 * Sets the name of the resulting JavaScript class (though the compiler will rename it if it would otherwise conflict with other variables in scope).
 	 * If unspecified, will be inferred from `filename`
@@ -207,6 +207,12 @@ export interface ModuleCompileOptions {
 	 * Use this to filter out warnings. Return `true` to keep the warning, `false` to discard it.
 	 */
 	warningFilter?: (warning: Warning) => boolean;
+	/**
+	 * Indicates whether the source code is in Typescript or JavaScript.
+	 *
+	 * @default false
+	 */
+	typeScript?: boolean;
 }
 
 // The following two somewhat scary looking types ensure that certain types are required but can be undefined still

packages/svelte/src/compiler/validate-options.js

@@ -47,7 +47,8 @@ const common = {
 export const validate_module_options =
 	/** @type {Validator<ModuleCompileOptions, ValidatedModuleCompileOptions>} */ (
 		object({
-			...common
+			...common,
+			typeScript: boolean(false),
 		})
 	);
 

packages/svelte/tests/helpers.js

@@ -80,13 +80,14 @@ export async function compile_directory(
 			generate
 		};
 
-		if (file.endsWith('.js')) {
+		if (file.endsWith('.js') || file.endsWith('.ts')) {
 			const out = `${output_dir}/${file}`;
-			if (file.endsWith('.svelte.js')) {
+			if (file.endsWith('.svelte.js') || file.endsWith('.svelte.ts')) {
 				const compiled = compileModule(text, {
 					filename: opts.filename,
 					generate: opts.generate,
-					dev: opts.dev
+					dev: opts.dev,
+					typeScript: file.endsWith('.svelte.ts')
 				});
 				write(out, compiled.js.code.replace(`v${VERSION}`, 'VERSION'));
 			} else {

packages/svelte/tests/snapshot/samples/typescript-module/_expected/client/export.ts

@@ -0,0 +1 @@
+export * from '../../export.ts';

packages/svelte/tests/snapshot/samples/typescript-module/_expected/client/index.svelte.js

@@ -0,0 +1,8 @@
+import 'svelte/internal/disclose-version';
+import 'svelte/internal/flags/legacy';
+import * as $ from 'svelte/internal/client';
+import { random } from './module.svelte';
+
+export default function Typescript_module($$anchor) {
+
+}

packages/svelte/tests/snapshot/samples/typescript-module/_expected/client/module.svelte.ts

@@ -0,0 +1,5 @@
+/* module.svelte.ts generated by Svelte VERSION */
+import * as $ from 'svelte/internal/client';
+import { random } from './export';
+
+export { random };

packages/svelte/tests/snapshot/samples/typescript-module/_expected/server/export.ts

@@ -0,0 +1 @@
+export * from '../../export.ts';

packages/svelte/tests/snapshot/samples/typescript-module/_expected/server/index.svelte.js

@@ -0,0 +1,6 @@
+import * as $ from 'svelte/internal/server';
+import { random } from './module.svelte';
+
+export default function Typescript_module($$payload) {
+
+}

packages/svelte/tests/snapshot/samples/typescript-module/_expected/server/module.svelte.ts

@@ -0,0 +1,5 @@
+/* module.svelte.ts generated by Svelte VERSION */
+import * as $ from 'svelte/internal/server';
+import { random } from './export';
+
+export { random };

packages/svelte/tests/snapshot/samples/typescript-module/export.ts

@@ -0,0 +1 @@
+export const random = 42;

packages/svelte/tests/snapshot/samples/typescript-module/index.svelte

@@ -0,0 +1,3 @@
+<script>
+	import { random } from './module.svelte';
+</script>

packages/svelte/tests/snapshot/samples/typescript-module/module.svelte.ts

@@ -0,0 +1,3 @@
+import { random } from './export';
+
+export { random };

packages/svelte/types/index.d.ts

@@ -636,7 +636,7 @@ declare module 'svelte/compiler' {
 	 * */
 	export function compile(source: string, options: CompileOptions): CompileResult;
 	/**
-	 * `compileModule` takes your JavaScript source code containing runes, and turns it into a JavaScript module.
+	 * `compileModule` takes your JavaScript/TypeScript source code containing runes, and turns it into a JavaScript module.
 	 *
 	 * @param source The component source code
 	 * */
@@ -788,7 +788,7 @@ declare module 'svelte/compiler' {
 		hash: (input: string) => string;
 	}) => string;
 
-	export interface CompileOptions extends ModuleCompileOptions {
+	export interface CompileOptions extends Omit<ModuleCompileOptions, 'typeScript'> {
 		/**
 		 * Sets the name of the resulting JavaScript class (though the compiler will rename it if it would otherwise conflict with other variables in scope).
 		 * If unspecified, will be inferred from `filename`
@@ -938,6 +938,12 @@ declare module 'svelte/compiler' {
 		 * Use this to filter out warnings. Return `true` to keep the warning, `false` to discard it.
 		 */
 		warningFilter?: (warning: Warning) => boolean;
+		/**
+		 * Indicates whether the source code is in Typescript or JavaScript.
+		 *
+		 * @default false
+		 */
+		typeScript?: boolean;
 	}
 	/**
 	 * - `html`    — the default, for e.g. `<div>` or `<span>`
@@ -2661,7 +2667,7 @@ declare module 'svelte/types/compiler/interfaces' {
 		hash: (input: string) => string;
 	}) => string;
 
-	interface CompileOptions_1 extends ModuleCompileOptions {
+	interface CompileOptions_1 extends Omit<ModuleCompileOptions, 'typeScript'> {
 		/**
 		 * Sets the name of the resulting JavaScript class (though the compiler will rename it if it would otherwise conflict with other variables in scope).
 		 * If unspecified, will be inferred from `filename`
@@ -2811,6 +2817,12 @@ declare module 'svelte/types/compiler/interfaces' {
 		 * Use this to filter out warnings. Return `true` to keep the warning, `false` to discard it.
 		 */
 		warningFilter?: (warning: Warning_1) => boolean;
+		/**
+		 * Indicates whether the source code is in Typescript or JavaScript.
+		 *
+		 * @default false
+		 */
+		typeScript?: boolean;
 	}
 	/**
 	 * - `html`    — the default, for e.g. `<div>` or `<span>`