From faf48e9b166e3e6e2ce90bd1349d526c7e53c890 Mon Sep 17 00:00:00 2001
From: Sam Zhou <sam@developersam.com>
Date: Fri, 22 May 2020 05:04:40 -0400
Subject: [PATCH] fix(v2): Resolve plugins relative to siteDir (#2789)

---
 packages/docusaurus/src/server/plugins/init.ts | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/packages/docusaurus/src/server/plugins/init.ts b/packages/docusaurus/src/server/plugins/init.ts
index 244483467e..de8d098fd8 100644
--- a/packages/docusaurus/src/server/plugins/init.ts
+++ b/packages/docusaurus/src/server/plugins/init.ts
@@ -5,6 +5,7 @@
  * LICENSE file in the root directory of this source tree.
  */
 
+import Module from 'module';
 import importFresh from 'import-fresh';
 import {LoadContext, Plugin, PluginConfig} from '@docusaurus/types';
 
@@ -15,9 +16,16 @@ export function initPlugins({
   pluginConfigs: PluginConfig[];
   context: LoadContext;
 }): Plugin<any>[] {
+  // We need to resolve plugins from the perspective of the siteDir, since the siteDir's package.json
+  // declares the dependency on these plugins.
+  // We need to fallback to createRequireFromPath since createRequire is only available in node v12.
+  // See: https://nodejs.org/api/modules.html#modules_module_createrequire_filename
+  const createRequire = Module.createRequire || Module.createRequireFromPath;
+  const pluginRequire = createRequire(context.siteDir);
+
   const plugins: Plugin<any>[] = pluginConfigs
     .map((pluginItem) => {
-      let pluginModuleImport;
+      let pluginModuleImport: string | undefined;
       let pluginOptions = {};
 
       if (!pluginItem) {
@@ -37,7 +45,9 @@ export function initPlugins({
 
       // The pluginModuleImport value is any valid
       // module identifier - npm package or locally-resolved path.
-      const pluginModule: any = importFresh(pluginModuleImport);
+      const pluginModule: any = importFresh(
+        pluginRequire.resolve(pluginModuleImport),
+      );
       return (pluginModule.default || pluginModule)(context, pluginOptions);
     })
     .filter(Boolean);