fix: tolerate pnpm-backed runtime dependency installs

test/scripts/postinstall-bundled-plugins.test.ts

@@ -2,6 +2,8 @@ import fs from "node:fs/promises";
 import path from "node:path";
 import { describe, expect, it, vi } from "vitest";
 import {
+  createBundledRuntimeDependencyInstallArgs,
+  createBundledRuntimeDependencyInstallEnv,
   createNestedNpmInstallEnv,
   pruneInstalledPackageDist,
   discoverBundledPluginRuntimeDeps,
@@ -47,14 +49,7 @@ async function writePluginPackage(
 
 describe("bundled plugin postinstall", () => {
   function createNpmInstallArgs(...packages: string[]) {
-    return [
-      "install",
-      "--omit=dev",
-      "--no-save",
-      "--package-lock=false",
-      "--legacy-peer-deps",
-      ...packages,
-    ];
+    return createBundledRuntimeDependencyInstallArgs(packages);
   }
 
   function createBareNpmRunner(packages: string[]) {
@@ -122,6 +117,25 @@ describe("bundled plugin postinstall", () => {
     });
   });
 
+  it("uses package-manager-neutral runtime install args with npm config env", () => {
+    expect(createBundledRuntimeDependencyInstallArgs(["acpx@0.4.1"])).toEqual([
+      "install",
+      "--ignore-scripts",
+      "acpx@0.4.1",
+    ]);
+    expect(
+      createBundledRuntimeDependencyInstallEnv({
+        HOME: "/tmp/home",
+        npm_config_prefix: "/opt/homebrew",
+      }),
+    ).toEqual({
+      HOME: "/tmp/home",
+      npm_config_legacy_peer_deps: "true",
+      npm_config_package_lock: "false",
+      npm_config_save: "false",
+    });
+  });
+
   it("does not install bundled plugin deps outside of source checkouts by default", async () => {
     const extensionsDir = await createExtensionsDir();
     const packageRoot = path.dirname(path.dirname(extensionsDir));