fix: global update should not fail if no packages are found (#8829)

ref #7898

.changeset/old-kings-wait.md

@@ -0,0 +1,6 @@
+---
+"@pnpm/plugin-commands-installation": patch
+"pnpm": patch
+---
+
+`pnpm update --global` should not crash if there are no any global packages installed [#7898](https://github.com/pnpm/pnpm/issues/7898).

pkg-manager/plugin-commands-installation/src/update/index.ts

@@ -171,6 +171,9 @@ export async function handler (
   opts: UpdateCommandOptions,
   params: string[] = []
 ): Promise<string | undefined> {
+  if (opts.global && opts.rootProjectManifest == null) {
+    return 'No global packages found'
+  }
   if (opts.interactive) {
     return interactiveUpdate(params, opts)
   }

pnpm/test/install/global.ts

@@ -7,6 +7,7 @@ import isWindows from 'is-windows'
 import {
   addDistTag,
   execPnpm,
+  execPnpmSync,
 } from '../utils'
 
 test('global installation', async () => {
@@ -102,3 +103,14 @@ test('global update to latest', async () => {
   const { default: isPositive } = await import(path.join(globalPrefix, 'node_modules/is-positive/package.json'))
   expect(isPositive.version).toBe('3.1.0')
 })
+
+test('global update should not crash if there are no global packages', async () => {
+  prepare()
+  const global = path.resolve('..', 'global')
+  const pnpmHome = path.join(global, 'pnpm')
+  fs.mkdirSync(global)
+
+  const env = { [PATH_NAME]: pnpmHome, PNPM_HOME: pnpmHome, XDG_DATA_HOME: global }
+
+  expect(execPnpmSync(['update', '--global'], { env }).status).toBe(0)
+})