refactor!: stop removing old .pnp.js files when migrating

.yarn/versions/db20fa43.yml

@@ -0,0 +1,23 @@
+releases:
+  "@yarnpkg/cli": major
+  "@yarnpkg/plugin-pnp": major
+
+declined:
+  - "@yarnpkg/plugin-compat"
+  - "@yarnpkg/plugin-constraints"
+  - "@yarnpkg/plugin-dlx"
+  - "@yarnpkg/plugin-essentials"
+  - "@yarnpkg/plugin-init"
+  - "@yarnpkg/plugin-interactive-tools"
+  - "@yarnpkg/plugin-nm"
+  - "@yarnpkg/plugin-npm-cli"
+  - "@yarnpkg/plugin-pack"
+  - "@yarnpkg/plugin-patch"
+  - "@yarnpkg/plugin-pnpm"
+  - "@yarnpkg/plugin-stage"
+  - "@yarnpkg/plugin-typescript"
+  - "@yarnpkg/plugin-version"
+  - "@yarnpkg/plugin-workspace-tools"
+  - "@yarnpkg/builder"
+  - "@yarnpkg/core"
+  - "@yarnpkg/doctor"

CHANGELOG.md

@@ -21,6 +21,7 @@ Yarn now accepts sponsorships! Please give a look at our [OpenCollective](https:
 - `yarn workspaces foreach` now automatically enables the `-v,--verbose` flag in interactive terminal environments.
 - `yarn npm audit` no longer takes into account publish registries. Use [`npmAuditRegistry`](https://yarnpkg.com/configuration/yarnrc#npmAuditRegistry) instead.
 - The `--assume-fresh-project` flag of `yarn init` has been removed. Should only affect people initializing Yarn 4+ projects using a Yarn 2 binary.
+- Yarn will no longer remove the old Yarn 2.x `.pnp.js` file when migrating.
 
 ### **API Changes**
 

packages/acceptance-tests/pkg-tests-specs/sources/pnp.test.js

@@ -952,9 +952,9 @@ describe(`Plug'n'Play`, () => {
       async ({path, run, source}) => {
         await run(`install`);
 
-        const pnpJs = await readFile(`${path}/.pnp.cjs`, `utf8`);
+        const pnpCjs = await readFile(`${path}/.pnp.cjs`, `utf8`);
 
-        expect(pnpJs.replace(/(\r\n|\r|\n).*/s, ``)).toMatch(/^#!foo$/);
+        expect(pnpCjs.replace(/(\r\n|\r|\n).*/s, ``)).toMatch(/^#!foo$/);
       },
     ),
   );

packages/plugin-pnp/sources/PnpLinker.ts

@@ -243,12 +243,6 @@ export class PnpInstaller implements Installer {
 
     const pnpPath = getPnpPath(this.opts.project);
 
-    if (xfs.existsSync(pnpPath.cjsLegacy)) {
-      this.opts.report.reportWarning(MessageName.UNNAMED, `Removing the old ${formatUtils.pretty(this.opts.project.configuration, Filename.pnpJs, formatUtils.Type.PATH)} file. You might need to manually update existing references to reference the new ${formatUtils.pretty(this.opts.project.configuration, Filename.pnpCjs, formatUtils.Type.PATH)} file. If you use Editor SDKs, you'll have to rerun ${formatUtils.pretty(this.opts.project.configuration, `yarn sdks`, formatUtils.Type.CODE)}.`);
-
-      await xfs.removePromise(pnpPath.cjsLegacy);
-    }
-
     if (!this.isEsmEnabled())
       await xfs.removePromise(pnpPath.esmLoader);
 

packages/plugin-pnp/sources/index.ts

@@ -15,7 +15,6 @@ export {pnpUtils};
 export const getPnpPath = (project: Project) => {
   return {
     cjs: ppath.join(project.cwd, Filename.pnpCjs),
-    cjsLegacy: ppath.join(project.cwd, Filename.pnpJs),
     esmLoader: ppath.join(project.cwd, `.pnp.loader.mjs` as Filename),
   };
 };