Allow exceptions

Author: davidmyersdev

README.md

@@ -40,9 +40,23 @@ Pass an object to `externalizeDeps` to override the default configuration.
 externalizeDeps({
   deps: true,
   devDeps: false,
+  except: [],
   nodeBuiltins: true,
   optionalDeps: true,
   peerDeps: true,
   useFile: join(process.cwd(), 'package.json'),
 })
 ```
+
+To _include_ specific dependencies in your bundle, you can add exceptions with the `except` option.
+
+```ts
+externalizeDeps({
+  except: [
+    // Match exact values with strings.
+    '@some/obscure/dependency',
+    // Or match patterns with regular expressions.
+    /^@some\/obscure(?:\/.+)?$/,
+  ],
+})
+```

src/index.ts

@@ -6,6 +6,7 @@ import type { Plugin } from 'vite'
 interface UserOptions {
   deps: boolean,
   devDeps: boolean,
+  except: Array<string | RegExp>,
   nodeBuiltins: boolean,
   optionalDeps: boolean,
   peerDeps: boolean,
@@ -16,10 +17,41 @@ const parseFile = (file: string) => {
   return JSON.parse(readFileSync(file).toString())
 }
 
+/**
+ * Returns a Vite plugin to exclude dependencies from the bundle.
+ *
+ * @example
+ *
+ * ```ts
+ * // vite.config.ts
+ * import { defineConfig } from 'vite'
+ * import { externalizeDeps } from 'vite-plugin-externalize-deps'
+ *
+ * export default defineConfig({
+ *   plugins: [
+ *     externalizeDeps({
+ *       deps: true,
+ *       devDeps: false,
+ *       except: [
+ *         // Match exact values with strings.
+ *         '@some/obscure/dependency',
+ *         // Or match patterns with regular expressions.
+ *         /^@some\/obscure(?:\/.+)?$/,
+ *       ],
+ *       nodeBuiltins: true,
+ *       optionalDeps: true,
+ *       peerDeps: true,
+ *       useFile: join(process.cwd(), 'package.json'),
+ *     }),
+ *   ],
+ * })
+ * ```
+ */
 export const externalizeDeps = (options: Partial<UserOptions> = {}): Plugin => {
   const optionsResolved: UserOptions = {
     deps: true,
     devDeps: false,
+    except: [],
     nodeBuiltins: true,
     optionalDeps: true,
     peerDeps: true,
@@ -83,12 +115,27 @@ export const externalizeDeps = (options: Partial<UserOptions> = {}): Plugin => {
         })
       }
 
+      const depMatchers = Array.from(externalDeps)
+      const isException = (id: string) => {
+        return optionsResolved.except.some((exception) => {
+          if (typeof exception === 'string') {
+            return exception === id
+          }
+
+          return exception.test(id)
+        })
+      }
+
       return {
         build: {
           rollupOptions: {
-            external: [
-              ...externalDeps.values(),
-            ],
+            external: (id) => {
+              if (isException(id)) {
+                return false
+              }
+
+              return depMatchers.some((depMatcher) => depMatcher.test(id))
+            },
           },
         },
       }