From f590942465f467c4dc542151f747a5bfb119d899 Mon Sep 17 00:00:00 2001
From: Kyle Ruzic <kyruzic@gmail.com>
Date: Thu, 3 Feb 2022 13:56:06 -0700
Subject: [PATCH] feat(plugin-webpack): allow specifing a seperate webpack
 config for your preload (#2679)

* feat(plugin-webpack): allow specifing a seperate webpack config for your preload

* feat(plugin-webpack): run prettier and lint
---
 packages/plugin/webpack/src/Config.ts         |  5 +++
 packages/plugin/webpack/src/WebpackConfig.ts  |  2 +-
 .../plugin/webpack/test/WebpackConfig_spec.ts | 36 +++++++++++++++++++
 3 files changed, 42 insertions(+), 1 deletion(-)

diff --git a/packages/plugin/webpack/src/Config.ts b/packages/plugin/webpack/src/Config.ts
index 4af7e45a1d..faf2cf6868 100644
--- a/packages/plugin/webpack/src/Config.ts
+++ b/packages/plugin/webpack/src/Config.ts
@@ -45,6 +45,11 @@ export interface WebpackPreloadEntryPoint {
    * entry files into your application.
    */
   prefixedEntries?: string[];
+  /**
+   * The optional webpack config for your preload process, defaults to the
+   * renderer webpack config if blank
+   */
+  config?: WebpackConfiguration | string;
 }
 
 export interface WebpackPluginRendererConfig {
diff --git a/packages/plugin/webpack/src/WebpackConfig.ts b/packages/plugin/webpack/src/WebpackConfig.ts
index 6b40253844..479a7bbda8 100644
--- a/packages/plugin/webpack/src/WebpackConfig.ts
+++ b/packages/plugin/webpack/src/WebpackConfig.ts
@@ -142,7 +142,7 @@ export default class WebpackConfigGenerator {
   }
 
   async getPreloadRendererConfig(parentPoint: WebpackPluginEntryPoint, entryPoint: WebpackPreloadEntryPoint): Promise<Configuration> {
-    const rendererConfig = this.resolveConfig(this.pluginConfig.renderer.config);
+    const rendererConfig = this.resolveConfig(entryPoint.config || this.pluginConfig.renderer.config);
     const prefixedEntries = entryPoint.prefixedEntries || [];
 
     return webpackMerge(
diff --git a/packages/plugin/webpack/test/WebpackConfig_spec.ts b/packages/plugin/webpack/test/WebpackConfig_spec.ts
index 59b6c6254e..720fef608a 100644
--- a/packages/plugin/webpack/test/WebpackConfig_spec.ts
+++ b/packages/plugin/webpack/test/WebpackConfig_spec.ts
@@ -332,6 +332,42 @@ describe('WebpackConfigGenerator', () => {
       );
       expect(webpackConfig.target).to.equal('electron-preload');
     });
+
+    it('allows you to specify a preload webpack config', async () => {
+      const config = {
+        renderer: {
+          config: {
+            name: 'renderer',
+            target: 'web',
+            entry: 'renderer',
+          },
+          entryPoints: [
+            {
+              name: 'main',
+              preload: {
+                js: 'preload.js',
+                config: {
+                  name: 'preload',
+                  target: 'electron-preload',
+                  entry: 'preload',
+                },
+              },
+            },
+          ],
+        },
+      } as WebpackPluginConfig;
+      const generator = new WebpackConfigGenerator(config, mockProjectDir, true, 3000);
+      const entryPoint = config.renderer.entryPoints[0];
+      const preloadWebpackConfig = await generator.getPreloadRendererConfig(
+        entryPoint,
+        // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+        entryPoint.preload!
+      );
+      const rendererWebpackConfig = await generator.getRendererConfig(config.renderer.entryPoints);
+      // Our preload config plugins is an empty list while our renderer config plugins has a member
+      expect(preloadWebpackConfig.name).to.equal('preload');
+      expect(rendererWebpackConfig.name).to.equal('renderer');
+    });
   });
 
   describe('getRendererConfig', () => {