fix: multiple plugin versions in a monorepo setup

packages/build/package.json

@@ -112,7 +112,7 @@
     "ps-list": "^8.0.0",
     "read-package-up": "^11.0.0",
     "readdirp": "^3.4.0",
-    "resolve": "^2.0.0-next.1",
+    "resolve": "^2.0.0-next.5",
     "rfdc": "^1.3.0",
     "safe-json-stringify": "^1.2.0",
     "semver": "^7.3.8",

packages/build/src/plugins/resolve.js

@@ -37,7 +37,7 @@ export const resolvePluginsPath = async function ({
 }) {
   const autoPluginsDir = getAutoPluginsDir(buildDir, packagePath)
   const pluginsOptionsA = await Promise.all(
-    pluginsOptions.map((pluginOptions) => resolvePluginPath({ pluginOptions, buildDir, autoPluginsDir })),
+    pluginsOptions.map((pluginOptions) => resolvePluginPath({ pluginOptions, buildDir, packagePath, autoPluginsDir })),
   )
   const pluginsOptionsB = await addPluginsNodeVersion({
     featureFlags,
@@ -100,24 +100,25 @@ const resolvePluginPath = async function ({
   pluginOptions,
   pluginOptions: { packageName, loadedFrom },
   buildDir,
+  packagePath,
   autoPluginsDir,
 }) {
   // Core plugins
   if (loadedFrom !== undefined) {
     return pluginOptions
   }
 
-  const localPackageName = normalizeLocalPackageName(packageName)
-
   // Local plugins
+  const localPackageName = normalizeLocalPackageName(packageName)
   if (localPackageName.startsWith('.')) {
     const { path: localPath, error } = await tryResolvePath(localPackageName, buildDir)
     validateLocalPluginPath(error, localPackageName)
     return { ...pluginOptions, pluginPath: localPath, loadedFrom: 'local' }
   }
 
   // Plugin added to `package.json`
-  const { path: manualPath } = await tryResolvePath(packageName, buildDir)
+  const packageDir = join(buildDir, packagePath || '')
+  const { path: manualPath } = await tryResolvePath(packageName, packageDir)
   if (manualPath !== undefined) {
     return { ...pluginOptions, pluginPath: manualPath, loadedFrom: 'package.json' }
   }

packages/build/tests/plugins/fixtures/monorepo/apps/pinned/package.json

@@ -0,0 +1,11 @@
+{
+  "name": "module_plugin",
+  "version": "0.0.1",
+  "type": "module",
+  "description": "test",
+  "license": "MIT",
+  "repository": "test",
+  "dependencies": {
+    "netlify-plugin-test": "8.2.0"
+  }
+}

packages/build/tests/plugins/fixtures/monorepo/apps/unpinned/netlify.toml

@@ -0,0 +1,5 @@
+[build]
+publish = "/"
+
+[[plugins]]
+package = "netlify-plugin-test"

packages/build/tests/plugins/fixtures/monorepo/apps/unpinned/package.json

@@ -0,0 +1,11 @@
+{
+  "name": "module_plugin",
+  "version": "0.0.1",
+  "type": "module",
+  "description": "test",
+  "license": "MIT",
+  "repository": "test",
+  "dependencies": {
+    "netlify-plugin-test": "^8.5.3"
+  }
+}

packages/build/tests/plugins/fixtures/monorepo/package.json

@@ -0,0 +1,6 @@
+{
+    "name": "module_multiple",
+    "workspaces": [
+      "apps/*"
+    ]
+}

packages/build/tests/plugins/tests.js

@@ -86,6 +86,15 @@ test('Resolution is relative to the build directory', async (t) => {
   t.snapshot(normalizeOutput(output))
 })
 
+test('Resolution respects monorepo node module resolution rules', async (t) => {
+  const fixture = await new Fixture('./fixtures/monorepo')
+  const output = await fixture.withFlags({ packagePath: 'apps/unpinned' }).runWithBuild()
+  // fixture has 2 versions of the same build plugin used by different workspaces
+  // this ensures version used by apps/unpinned is used instead of version that
+  // is hoisted in shared monorepo node_modules
+  t.assert(output.indexOf('@8.5.3') > 0)
+})
+
 test('Non-existing plugins', async (t) => {
   const output = await new Fixture('./fixtures/non_existing').runWithBuild()
   t.snapshot(normalizeOutput(output))