fix(migrate): 4 PR-review fixes (bridge resolve, force-stage, prettier gate, preview registry)

Addresses four Codex review comments on PR #1891, all verified valid:

- install.sh: `resolve_bridge_commit_version ... || true` so `set -e` does not
  abort at the assignment before the "Could not resolve" error prints (the
  installer otherwise fails silently on an unregistered/transient bridge miss).
- test-pkg-pr-new-migrate.sh: only force-stage `.npmrc`/`.yarnrc.yml` that carry
  the bridge marker, not a pre-existing ignored file that may hold private
  registry auth tokens the migration never touched.
- migration/bin.ts: detect Prettier unconditionally on existing-Vite+ upgrades so
  the format gate skips Oxfmt on a Prettier project even on a non-`--full`
  upgrade; the Prettier migration itself stays gated on `--full`.
- preview-registry.ts: thread the detected package manager into
  reconcilePreviewBridgeRegistry so a pnpm/npm/bun project with a stray
  `.yarnrc.yml` still gets `.npmrc` (its install reads `.npmrc`). Adds a test.

Claude-Session: https://claude.ai/code/session_01DQhS6o1fyQd1yjiee6W8jR

Author: fengmk2

.github/scripts/test-pkg-pr-new-migrate.sh

@@ -299,8 +299,14 @@ if [ "$is_git_repo" -eq 1 ]; then
   # the project's CI: the commit build then resolves from the default registry,
   # which has no 0.0.0-commit.<sha>, and the supply-chain policy check rejects the
   # lockfile (ERR_PNPM_TARBALL_URL_MISMATCH). Stage whichever file migrate wrote.
-  git -C "$project_dir" add -f .npmrc 2>/dev/null || true
-  git -C "$project_dir" add -f .yarnrc.yml 2>/dev/null || true
+  # Only stage config that carries the bridge marker, i.e. was written for this
+  # run. A pre-existing ignored `.npmrc`/`.yarnrc.yml` (private-registry auth
+  # tokens) that migrate never touched must not land in the migration diff.
+  for cfg in .npmrc .yarnrc.yml; do
+    if [ -f "$project_dir/$cfg" ] && grep -q "registry-bridge.viteplus.dev" "$project_dir/$cfg" 2>/dev/null; then
+      git -C "$project_dir" add -f "$cfg" 2>/dev/null || true
+    fi
+  done
   echo
   echo "Migration worktree changes (.npmrc force-staged so it survives .gitignore):"
   git -C "$project_dir" status --short

packages/cli/install.sh

@@ -898,7 +898,10 @@ main() {
     # immutable commit version (0.0.0-commit.<sha>), the clearly-defined test
     # version we install. The directory label stays non-semver so it keeps out
     # of cleanup_old_versions and makes the PR build obvious in `~/.vite-plus/`.
-    PR_COMMIT_VERSION="$(resolve_bridge_commit_version "$PR_VERSION")"
+    # `|| true` keeps `set -e` from aborting this assignment when resolution
+    # fails (unregistered ref / transient bridge error), so the actionable
+    # error below is reachable instead of the installer exiting silently.
+    PR_COMMIT_VERSION="$(resolve_bridge_commit_version "$PR_VERSION" || true)"
     if [ -z "$PR_COMMIT_VERSION" ]; then
       error "Could not resolve a registry bridge build for ${PR_VERSION}"
     fi

packages/cli/src/migration/bin.ts

@@ -1291,18 +1291,16 @@ async function main() {
       eslintMigrated = true;
     }
 
-    // Prettier migration is part of the full setup bucket. Default upgrades skip
-    // detection entirely; the variables stay at their no-prettier defaults so the
-    // formatting gate and summary below still compile and behave correctly.
-    let prettierProject: { hasDependency: boolean; configFile?: string } = {
-      hasDependency: false,
-    };
+    // Detect Prettier unconditionally so the formatting gate below skips Oxfmt on
+    // a project that still uses Prettier, even on a bare (non-`--full`) upgrade
+    // that rewrites imports/scripts. The Prettier MIGRATION itself stays in the
+    // full-setup bucket.
+    const prettierProject = detectPrettierProject(
+      workspaceInfoOptional.rootDir,
+      workspaceInfoOptional.packages,
+    );
     let prettierMigrated = false;
     if (fullSetup) {
-      prettierProject = detectPrettierProject(
-        workspaceInfoOptional.rootDir,
-        workspaceInfoOptional.packages,
-      );
       if (prettierProject.hasDependency && prettierProject.configFile) {
         // Interactive only: stop any active spinner (e.g. "Migrating ESLint") so
         // it does not animate beneath the confirm prompt.

packages/cli/src/utils/__tests__/preview-registry.spec.ts

@@ -4,6 +4,7 @@ import path from 'node:path';
 
 import { afterEach, beforeEach, describe, expect, it } from 'vitest';
 
+import { PackageManager } from '../../types/index.ts';
 import { isPreviewVitePlusVersion, reconcilePreviewBridgeRegistry } from '../preview-registry.ts';
 
 const PREVIEW = '0.0.0-commit.81dee3abe99a61a28ebf112da4f76f2a32aec8b4';
@@ -49,6 +50,16 @@ describe('reconcilePreviewBridgeRegistry', () => {
     expect(fs.existsSync(path.join(dir, '.yarnrc.yml'))).toBe(false);
   });
 
+  // PR #1891 review: a non-Yarn package manager must get `.npmrc` even when a
+  // stray `.yarnrc.yml` is present, or its install reads `.npmrc` and can't
+  // resolve `0.0.0-commit.<sha>` from the default registry.
+  it('writes .npmrc for a non-Yarn package manager despite a stray .yarnrc.yml', () => {
+    fs.writeFileSync(path.join(dir, '.yarnrc.yml'), 'nodeLinker: node-modules\n');
+    expect(reconcilePreviewBridgeRegistry(dir, PREVIEW, PackageManager.pnpm)).toBe(true);
+    expect(fs.existsSync(path.join(dir, '.npmrc'))).toBe(true);
+    expect(fs.readFileSync(path.join(dir, '.npmrc'), 'utf8')).toContain(`registry=${BRIDGE}`);
+  });
+
   it('appends to an existing .npmrc without clobbering it', () => {
     fs.writeFileSync(path.join(dir, '.npmrc'), '@scope:registry=https://npm.example.com/\n');
     reconcilePreviewBridgeRegistry(dir, PREVIEW);

packages/cli/src/utils/preview-registry.ts

@@ -1,6 +1,7 @@
 import fs from 'node:fs';
 import path from 'node:path';
 
+import { PackageManager } from '../types/index.ts';
 import { VITE_PLUS_VERSION } from './constants.ts';
 import { readJsonFile } from './json.ts';
 import { editYamlFile } from './yaml.ts';
@@ -159,9 +160,19 @@ function clearYarnBerryRegistry(projectRoot: string): boolean {
 export function reconcilePreviewBridgeRegistry(
   projectRoot: string,
   version: string = process.env.VP_VERSION || VITE_PLUS_VERSION,
+  packageManager?: PackageManager,
 ): boolean {
   if (isPreviewVitePlusVersion(version)) {
-    if (isYarnBerryProject(projectRoot)) {
+    // Write the file the ACTIVE package manager reads: Yarn Berry uses
+    // `.yarnrc.yml`, everything else uses `.npmrc`. Fall back to file-based
+    // detection only when the manager is unknown, so a stray leftover
+    // `.yarnrc.yml` in a pnpm/npm/bun project doesn't leave `.npmrc` without the
+    // bridge registry (the install would then fail to resolve `0.0.0-commit.<sha>`).
+    const useYarnBerry =
+      packageManager === PackageManager.yarn
+        ? isYarnBerryProject(projectRoot)
+        : packageManager === undefined && isYarnBerryProject(projectRoot);
+    if (useYarnBerry) {
       ensureYarnBerryRegistry(projectRoot);
     } else {
       ensureNpmrcRegistry(projectRoot);

packages/cli/src/utils/prompts.ts

@@ -116,7 +116,7 @@ export async function runViteInstall(
   // run left behind so installs don't hit the test bridge. No-op for a real build
   // with no leftover. Done before the VP_SKIP_INSTALL return so it persists for
   // the project's own CI even when this run skips the install.
-  reconcilePreviewBridgeRegistry(cwd);
+  reconcilePreviewBridgeRegistry(cwd, undefined, options?.packageManager);
 
   // install dependencies on non-CI environment
   if (process.env.VP_SKIP_INSTALL) {