fix: resolving peers from root of workspace when adding new dep (#3667)

.changeset/purple-files-clap.md

@@ -0,0 +1,5 @@
+---
+"@pnpm/plugin-commands-installation": patch
+---
+
+Peer depednencies are resolved from the root of the workspace when a new dependency is added to the root of the workspace.

packages/plugin-commands-installation/src/recursive.ts

@@ -96,7 +96,7 @@ export default async function recursive (
     return false
   }
   const manifestsByPath: { [dir: string]: Omit<Project, 'dir'> } = {}
-  for (const { dir, manifest, writeProjectManifest } of pkgs) {
+  for (const { dir, manifest, writeProjectManifest } of allProjects) {
     manifestsByPath[dir] = { manifest, writeProjectManifest }
   }
 
@@ -241,6 +241,19 @@ export default async function recursive (
         } as MutatedProject)
       }
     }))
+    if (!opts.selectedProjectsGraph[opts.workspaceDir] && manifestsByPath[opts.workspaceDir] != null) {
+      const localConfig = await memReadLocalConfig(opts.workspaceDir)
+      const modulesDir = localConfig.modulesDir ?? opts.modulesDir
+      const { manifest, writeProjectManifest } = manifestsByPath[opts.workspaceDir]
+      writeProjectManifests.push(writeProjectManifest)
+      mutatedImporters.push({
+        buildIndex: 0,
+        manifest,
+        modulesDir,
+        mutation: 'install',
+        rootDir: opts.workspaceDir,
+      } as MutatedProject)
+    }
     if ((mutatedImporters.length === 0) && cmdFullName === 'update') {
       throw new PnpmError('NO_PACKAGE_IN_DEPENDENCIES',
         'None of the specified packages were found in the dependencies of any of the projects.')

packages/pnpm/test/monorepo/index.ts

@@ -1393,3 +1393,32 @@ test('pnpm run should include the workspace root when --workspace-root option is
   expect(await exists('test')).toBeTruthy()
   expect(await exists('project/test')).toBeTruthy()
 })
+
+test('peer dependencies are resolved from the root of the workspace when a new dependency is added to a workspace project', async () => {
+  const projects = preparePackages([
+    {
+      location: '.',
+      package: {
+        name: 'project-1',
+        version: '1.0.0',
+
+        dependencies: {
+          ajv: '4.10.4',
+        },
+      },
+    },
+    {
+      name: 'project-2',
+      version: '1.0.0',
+    },
+  ])
+
+  await writeYamlFile('pnpm-workspace.yaml', { packages: ['**', '!store/**'] })
+
+  process.chdir('project-2')
+
+  await execPnpm(['add', 'ajv-keywords@1.5.0', '--strict-peer-dependencies'])
+
+  const lockfile = await projects['project-1'].readLockfile()
+  expect(lockfile.packages).toHaveProperty(['/ajv-keywords/1.5.0_ajv@4.10.4'])
+})