@sveltejs/package Customize behavior of copying package.json and other essential files to the output directory when packaging a Svelte library

.changeset/eighty-maps-talk.md

@@ -0,0 +1,5 @@
+---
+'@sveltejs/package': minor
+---
+
+Allow customization of metadata files copied during packaging with svelte-package

packages/kit/types/index.d.ts

@@ -175,6 +175,7 @@ export interface Config {
 		emitTypes?: boolean;
 		exports?(filepath: string): boolean;
 		files?(filepath: string): boolean;
+		metadata?(filepath: string): boolean;
 	};
 	/** Preprocessor options, if any. Preprocessing can alternatively also be done through Vite's preprocessor capabilities. */
 	preprocess?: any;

packages/package/src/config.js

@@ -32,7 +32,8 @@ function process_config(config, { cwd = process.cwd() } = {}) {
 			dir: config.package?.dir ?? 'package',
 			exports: config.package?.exports ?? ((filepath) => !/^_|\/_|\.d\.ts$/.test(filepath)),
 			files: config.package?.files ?? (() => true),
-			emitTypes: config.package?.emitTypes ?? true
+			emitTypes: config.package?.emitTypes ?? true,
+			metadata: config.package?.metadata ?? (() => true)
 		},
 		preprocess: config.preprocess
 	};

packages/package/src/index.js

@@ -61,7 +61,9 @@ export async function build(config, cwd = process.cwd()) {
 		}
 	}
 
-	write(join(dir, 'package.json'), JSON.stringify(pkg, null, 2));
+	if (config.package.metadata('package.json')) {
+		write(join(dir, 'package.json'), JSON.stringify(pkg, null, 2));
+	}
 
 	for (const file of files) {
 		await process_file(config, file);
@@ -75,6 +77,7 @@ export async function build(config, cwd = process.cwd()) {
 	for (const pathname of whitelist) {
 		const full_path = join(cwd, pathname);
 		if (fs.lstatSync(full_path).isDirectory()) continue; // just to be sure
+		if (!config.package.metadata(pathname)) continue;
 
 		const package_path = join(dir, pathname);
 		if (!fs.existsSync(package_path)) fs.copyFileSync(full_path, package_path);
@@ -160,7 +163,7 @@ export async function watch(config, cwd = process.cwd()) {
 				}
 			}
 
-			if (should_update_pkg) {
+			if (should_update_pkg && config.package.metadata('package.json')) {
 				const pkg = generate_pkg(cwd, files);
 				write(join(dir, 'package.json'), JSON.stringify(pkg, null, 2));
 				console.log('Updated package.json');

packages/package/test/fixtures/metadata-false/ReadMe.md

@@ -0,0 +1 @@
+Hello

packages/package/test/fixtures/metadata-false/expected/index.d.ts

@@ -0,0 +1,2 @@
+declare const _default: {};
+export default _default;

packages/package/test/fixtures/metadata-false/expected/index.js

@@ -0,0 +1 @@
+export default {};

packages/package/test/fixtures/metadata-false/jsconfig.json

@@ -0,0 +1 @@
+{}

packages/package/test/fixtures/metadata-false/package.json

@@ -0,0 +1,7 @@
+{
+	"name": "metadata-false",
+	"private": true,
+	"version": "1.0.0",
+	"description": "metadata false",
+	"type": "module"
+}

packages/package/test/fixtures/metadata-false/src/lib/index.js

@@ -0,0 +1 @@
+export default {};

packages/package/test/fixtures/metadata-false/svelte.config.js

@@ -0,0 +1,7 @@
+const config = {
+	package: {
+		metadata: () => false
+	}
+};
+
+export default config;

packages/package/test/fixtures/metadata-readmeOnly/ReadMe.md

@@ -0,0 +1 @@
+Hello

packages/package/test/fixtures/metadata-readmeOnly/expected/ReadMe.md

@@ -0,0 +1 @@
+Hello

packages/package/test/fixtures/metadata-readmeOnly/expected/index.d.ts

@@ -0,0 +1,2 @@
+declare const _default: {};
+export default _default;

packages/package/test/fixtures/metadata-readmeOnly/expected/index.js

@@ -0,0 +1 @@
+export default {};

packages/package/test/fixtures/metadata-readmeOnly/jsconfig.json

@@ -0,0 +1 @@
+{}

packages/package/test/fixtures/metadata-readmeOnly/package.json

@@ -0,0 +1,7 @@
+{
+	"name": "metadata-readme-only",
+	"private": true,
+	"version": "1.0.0",
+	"description": "metadata copy readme only",
+	"type": "module"
+}

packages/package/test/fixtures/metadata-readmeOnly/src/lib/index.js

@@ -0,0 +1 @@
+export default {};

packages/package/test/fixtures/metadata-readmeOnly/svelte.config.js

@@ -0,0 +1,7 @@
+const config = {
+	package: {
+		metadata: (filepath) => filepath === 'ReadMe.md'
+	}
+};
+
+export default config;

packages/package/test/index.js

@@ -130,6 +130,14 @@ test('create package with emitTypes settings disabled', async () => {
 	await test_make_package('emitTypes-false');
 });
 
+test('create package with no metadata', async () => {
+	await test_make_package('metadata-false');
+});
+
+test('create package with filtered metadata', async () => {
+	await test_make_package('metadata-readmeOnly');
+});
+
 test('create package and properly merge exports map', async () => {
 	await test_make_package('exports-merge');
 });

packages/package/types/index.d.ts

@@ -23,6 +23,10 @@ export interface PackageConfig {
 	 * Function that determines if the given file is part of the output.
 	 */
 	files?(filepath: string): boolean;
+	/**
+	 * Function that determines if the given metadata file is part of the output.
+	 */
+	metadata?(filepath: string): boolean;
 }
 
 export interface Config {