Preserve linked packages in create command (yarnpkg#7543)

* Preserve linked packages in create command

* Update changelog

* Warn when using linked package

* Update CHANGELOG.md

* Update link-resolver.js

CHANGELOG.md

@@ -4,6 +4,10 @@ Please add one entry in this file for each change in Yarn's behavior. Use the sa
 
 ## Master
 
+- Preserves linked packages when calling `yarn create`
+
+  [#7543](https://github.com/yarnpkg/yarn/pull/7543) - [**Nick McCurdy**](https://github.com/nickmccurdy)
+
 - Fixes the offline mirror filenames when using Verdaccio
 
   [#7499](https://github.com/yarnpkg/yarn/pull/7499) - [**xv2**](https://github.com/xv2)

src/cli/commands/create.js

@@ -5,6 +5,7 @@ import {MessageError} from '../../errors.js';
 import type {Reporter} from '../../reporters/index.js';
 import * as child from '../../util/child.js';
 import {makeEnv} from '../../util/execute-lifecycle-script';
+import * as fs from '../../util/fs.js';
 import {run as runGlobal, getBinFolder} from './global.js';
 
 const path = require('path');
@@ -58,7 +59,13 @@ export async function run(config: Config, reporter: Reporter, flags: Object, arg
   }
 
   const {fullName: packageName, name: commandName} = coerceCreatePackageName(builderName);
-  await runGlobal(config, reporter, {}, ['add', packageName]);
+
+  const linkLoc = path.join(config.linkFolder, commandName);
+  if (await fs.exists(linkLoc)) {
+    reporter.info(reporter.lang('linkUsing', packageName));
+  } else {
+    await runGlobal(config, reporter, {}, ['add', packageName]);
+  }
 
   const binFolder = await getBinFolder(config, {});
   const command = path.resolve(binFolder, commandName);

src/resolvers/exotics/link-resolver.js

@@ -30,9 +30,10 @@ export default class LinkResolver extends ExoticResolver {
     const name = path.basename(loc);
     const registry: RegistryNames = 'npm';
 
-    const manifest: Manifest = !await fs.exists(`${loc}/package.json`) || loc === this.config.lockfileFolder
-      ? {_uid: '', name, version: '0.0.0', _registry: registry}
-      : await this.config.readManifest(loc, this.registry);
+    const manifest: Manifest =
+      !await fs.exists(`${loc}/package.json`) || loc === this.config.lockfileFolder
+        ? {_uid: '', name, version: '0.0.0', _registry: registry}
+        : await this.config.readManifest(loc, this.registry);
 
     manifest._remote = {
       type: 'link',