vercel · chris-olszewski · Apr 9, 2025 · Apr 8, 2025 · Apr 8, 2025
@@ -104,6 +104,11 @@ impl LocalPackageDiscoveryBuilder {
     pub fn with_allow_no_package_manager(&mut self, allow_missing_package_manager: bool) {
         self.allow_missing_package_manager = allow_missing_package_manager;
     }
+
+    pub fn with_package_manager(&mut self, package_manager: Option<PackageManager>) -> &mut Self {
+        self.package_manager = package_manager;
+        self
+    }
 }
 
 impl PackageDiscoveryBuilder for LocalPackageDiscoveryBuilder {

@@ -80,6 +80,12 @@ impl<'a> PackageGraphBuilder<'a, LocalPackageDiscoveryBuilder> {
             .with_allow_no_package_manager(allow_no_package_manager);
         self
     }
+
+    pub fn with_package_manager(mut self, package_manager: PackageManager) -> Self {
+        self.package_discovery
+            .with_package_manager(Some(package_manager));
+        self
+    }
 }
 
 impl<'a, P> PackageGraphBuilder<'a, P> {

@@ -59,6 +59,22 @@ describe("affectedPackages", () => {
     });
   }
 
+  it("does not require packageManager for npm", async () => {
+    const dir = path.resolve(__dirname, "./fixtures/npm-monorepo");
+    const workspace = await Workspace.find(dir);
+
+    const reduced: PackageReduced[] = (
+      await workspace.affectedPackages(["apps/app/file.txt"])
+    ).map((pkg) => {
+      return {
+        name: pkg.name,
+        relativePath: pkg.relativePath,
+      };
+    });
+
+    assert.deepEqual(reduced, [{ name: "app-a", relativePath: "apps/app" }]);
+  });
+
   describe("optimizedLockfileUpdates", () => {
     it("errors if not provided comparison ref", async () => {
       const dir = path.resolve(__dirname, "./fixtures/monorepo");

@@ -0,0 +1,6 @@
+{
+  "name": "app-a",
+  "dependencies": {
+    "ui": "*"
+  }
+}
@@ -0,0 +1,5 @@
+{
+  "name": "basic",
+  "private": true,
+  "workspaces": ["apps/*", "packages/*"]
+}
@@ -0,0 +1,3 @@
+{
+  "//": "missing name field in this package.json"
+}
@@ -0,0 +1,3 @@
+{
+  "name": "ui"
+}
@@ -63,19 +63,22 @@ impl Workspace {
             })?;
         let workspace_state = WorkspaceState::infer(&reference_dir)?;
         let is_multi_package = workspace_state.mode == WorkspaceType::MultiPackage;
-        let package_manager_name = workspace_state
-            .package_manager
-            .as_ref()
-            .map_err(|error| Error::PackageManager {
-                error: error.to_string(),
-                path: workspace_state.root.clone(),
-            })?
-            .name();
+        let package_manager =
+            workspace_state
+                .package_manager
+                .as_ref()
+                .map_err(|error| Error::PackageManager {
+                    error: error.to_string(),
+                    path: workspace_state.root.clone(),
+                })?;
+
+        let package_manager_name = package_manager.name();
 
         let workspace_root = &workspace_state.root;
         let root_package_json = PackageJson::load(&workspace_root.join_component("package.json"))?;
         let package_graph = PackageGraphBuilder::new(workspace_root, root_package_json)
             .with_single_package_mode(!is_multi_package)
+            .with_package_manager(package_manager.clone())
             .build()
             .await?;