feat: add option disableDependencyReinclusion (#161)

* feat: add option disableDependencyReinclude

* fix: update lockfile for new test dependency

* refactor: rename option disableDependencyReinclude to disableDependencyReinclusion

* docs: add suggested changes

Co-authored-by: Ben McCann <322311+benmccann@users.noreply.github.com>

* docs: fix re-include example

Co-authored-by: Ben McCann <322311+benmccann@users.noreply.github.com>

Author: dominikg

.changeset/friendly-deers-own.md

@@ -0,0 +1,5 @@
+---
+'@sveltejs/vite-plugin-svelte': minor
+---
+
+Add option disableDependencyReinclusion to offer users a way out of automatic optimization for hybrid packages

docs/config.md

@@ -156,6 +156,21 @@ A [minimatch pattern](https://github.com/isaacs/minimatch), or array of patterns
 
   Some Vite plugins can contribute additional preprocessors by defining [api.sveltePreprocess](./faq.md#how-do-i-add-a-svelte-preprocessor-from-a-vite-plugin). If you don't want to use them, set this to true to ignore them all or use an array of strings with plugin names to specify which.
 
+### disableDependencyReinclusion
+
+- **Type:** `boolean | string[]`
+- **Default:** `false`
+
+  vite-plugin-svelte automatically manages [pre-bundling for Svelte components](./faq.md#what-is-going-on-with-vite-and-pre-bundling-dependencies).
+  To opt-out of this automatic behavior you can use
+
+  - `disableDependencyReinclusion: true` to disable all re-inclusions
+  - `disableDependencyReinclusion: ['foo']` to disable re-inclusions only for dependencies of `foo`.
+
+  If you want to manually re-include the dependency `bar`of `foo`, you can add `{optimizeDeps:{include:['foo > bar']}}` to your Vite config
+
+  > This is currently required for hybrid packages like Routify, that export both Node and browser code.
+
 ## Experimental options
 
 These options are considered experimental and breaking changes to them can occur in any release! Specify them under the `experimental` option.

packages/e2e-tests/_test_dependencies/svelte-hybrid/cli.js

@@ -0,0 +1,2 @@
+#!/usr/bin/env node
+console.log('hybrid svelte');

packages/e2e-tests/_test_dependencies/svelte-hybrid/index.js

@@ -0,0 +1,2 @@
+import Dependency from './src/components/Dependency.svelte';
+export default Dependency;

packages/e2e-tests/_test_dependencies/svelte-hybrid/package.json

@@ -0,0 +1,17 @@
+{
+  "version": "1.0.0",
+  "private": true,
+  "name": "e2e-test-dep-svelte-hybrid",
+  "bin": "cli.js",
+  "main": "index.js",
+  "svelte": "index.js",
+  "files": [
+    "index.js",
+    "cli.js",
+    "package.json"
+  ],
+  "dependencies": {
+    "@types/node": "^16.7.8",
+    "e2e-test-dep-cjs-only": "workspace:*"
+  }
+}

packages/e2e-tests/_test_dependencies/svelte-hybrid/src/components/Dependency.svelte

@@ -0,0 +1,18 @@
+<script>
+	const label = 'dependency-import';
+	import * as cjsOnly from 'e2e-test-dep-cjs-only';
+	const { cjs } = cjsOnly;
+</script>
+
+<div id="dependency-import"><span class="label">{label}</span></div>
+<div id="sticky-dep" class="sticky-dep">sticky-dep</div>
+<div id="cjs-only-dependency">{cjs()}</div>
+
+<style>
+	.label {
+		color: green;
+	}
+	.sticky-dep {
+		position: sticky;
+	}
+</style>

packages/e2e-tests/package-json-svelte-field/package.json

@@ -8,7 +8,8 @@
     "preview": "vite preview"
   },
   "dependencies": {
-    "e2e-test-dep-svelte-nested": "workspace:*"
+    "e2e-test-dep-svelte-nested": "workspace:*",
+    "e2e-test-dep-svelte-hybrid": "workspace:*"
   },
   "devDependencies": {
     "@sveltejs/vite-plugin-svelte": "workspace:*",

packages/e2e-tests/package-json-svelte-field/vite.config.js

@@ -3,7 +3,11 @@ const { defineConfig } = require('vite');
 
 module.exports = defineConfig(({ command, mode }) => {
 	return {
-		plugins: [svelte()],
+		plugins: [
+			svelte({
+				disableDependencyReinclusion: ['e2e-test-dep-svelte-hybrid']
+			})
+		],
 		build: {
 			// make build faster by skipping transforms and minification
 			target: 'esnext',

packages/vite-plugin-svelte/src/utils/__tests__/dependencies.spec.ts

@@ -13,10 +13,11 @@ describe('dependencies', () => {
 			const deps = findRootSvelteDependencies(
 				path.resolve('packages/e2e-tests/package-json-svelte-field')
 			);
-			expect(deps).toHaveLength(2);
+			expect(deps).toHaveLength(3);
 			expect(deps[0].name).toBe('e2e-test-dep-svelte-nested');
 			expect(deps[1].name).toBe('e2e-test-dep-svelte-simple');
 			expect(deps[1].path).toEqual(['e2e-test-dep-svelte-nested']);
+			expect(deps[2].name).toBe('e2e-test-dep-svelte-hybrid');
 		});
 	});
 });

packages/vite-plugin-svelte/src/utils/options.ts

@@ -27,6 +27,7 @@ const knownOptions = new Set([
 	'preprocess',
 	'hot',
 	'ignorePluginPreprocessors',
+	'disableDependencyReinclusion',
 	'experimental'
 ]);
 
@@ -184,7 +185,7 @@ export function buildExtraViteConfig(
 	// extra handling for svelte dependencies in the project
 	const svelteDeps = findRootSvelteDependencies(options.root);
 	const extraViteConfig: Partial<UserConfig> = {
-		optimizeDeps: buildOptimizeDepsForSvelte(svelteDeps, config.optimizeDeps),
+		optimizeDeps: buildOptimizeDepsForSvelte(svelteDeps, options, config.optimizeDeps),
 		resolve: {
 			mainFields: [...SVELTE_RESOLVE_MAIN_FIELDS],
 			dedupe: [...SVELTE_IMPORTS, ...SVELTE_HMR_IMPORTS]
@@ -214,6 +215,7 @@ export function buildExtraViteConfig(
 
 function buildOptimizeDepsForSvelte(
 	svelteDeps: SvelteDependency[],
+	options: ResolvedOptions,
 	optimizeDeps?: DepOptimizationOptions
 ): DepOptimizationOptions {
 	// include svelte imports for optimization unless explicitly excluded
@@ -244,18 +246,24 @@ function buildOptimizeDepsForSvelte(
 	log.debug(`automatically excluding found svelte dependencies: ${svelteDepsToExclude.join(', ')}`);
 	exclude.push(...svelteDepsToExclude.filter((x) => !isExcluded(x)));
 
-	const transitiveDepsToInclude = svelteDeps
-		.filter((dep) => isExcluded(dep.name))
-		.flatMap((dep) =>
-			Object.keys(dep.pkg.dependencies || {})
-				.filter((depOfDep) => !isExcluded(depOfDep))
-				.map((depOfDep) => dep.path.concat(dep.name, depOfDep).join(' > '))
+	if (options.disableDependencyReinclusion !== true) {
+		const disabledReinclusions = options.disableDependencyReinclusion || [];
+		if (disabledReinclusions.length > 0) {
+			log.debug(`not reincluding transitive dependencies of`, disabledReinclusions);
+		}
+		const transitiveDepsToInclude = svelteDeps
+			.filter((dep) => !disabledReinclusions.includes(dep.name) && isExcluded(dep.name))
+			.flatMap((dep) =>
+				Object.keys(dep.pkg.dependencies || {})
+					.filter((depOfDep) => !isExcluded(depOfDep))
+					.map((depOfDep) => dep.path.concat(dep.name, depOfDep).join(' > '))
+			);
+		log.debug(
+			`reincluding transitive dependencies of excluded svelte dependencies`,
+			transitiveDepsToInclude
 		);
-	log.debug(
-		`reincluding transitive dependencies of excluded svelte dependencies`,
-		transitiveDepsToInclude
-	);
-	include.push(...transitiveDepsToInclude);
+		include.push(...transitiveDepsToInclude);
+	}
 
 	return { include, exclude };
 }
@@ -372,6 +380,19 @@ export interface Options {
 	 */
 	ignorePluginPreprocessors?: boolean | string[];
 
+	/**
+	 * vite-plugin-svelte automatically handles excluding svelte libraries and reinclusion of their dependencies
+	 * in vite.optimizeDeps.
+	 *
+	 * `disableDependencyReinclusion: true` disables all reinclusions
+	 * `disableDependencyReinclusion: ['foo','bar']` disables reinclusions for dependencies of foo and bar
+	 *
+	 * This should be used for hybrid packages that contain both node and browser dependencies, eg Routify
+	 *
+	 * @default false
+	 */
+	disableDependencyReinclusion?: boolean | string[];
+
 	/**
 	 * These options are considered experimental and breaking changes to them can occur in any release
 	 */