feat: add a new option to the hoister to ignore some deps (#5784)

.changeset/healthy-snakes-change.md

@@ -0,0 +1,7 @@
+---
+"@pnpm/core": minor
+"@pnpm/headless": minor
+"@pnpm/real-hoist": minor
+---
+
+A new option added for avoiding hoisting some dependencies to the root of `node_modules`: `externalDependencies`. This option is a set of dependency names that were added to `node_modules` by another tool. pnpm doesn't have information about these dependencies but they shouldn't be overwritten by hoisted dependencies.

pkg-manager/core/src/install/extendInstallOptions.ts

@@ -28,6 +28,7 @@ export interface StrictInstallOptions {
   extraBinPaths: string[]
   extraEnv: Record<string, string>
   hoistingLimits?: HoistingLimits
+  externalDependencies?: Set<string>
   useLockfile: boolean
   saveLockfile: boolean
   useGitBranchLockfile: boolean

pkg-manager/core/test/hoistedNodeLinker/install.ts

@@ -224,3 +224,20 @@ test('hoistingLimits should prevent packages to be hoisted', async () => {
   expect(fs.existsSync('node_modules/ms')).toBeFalsy()
   expect(fs.existsSync('node_modules/send/node_modules/ms')).toBeTruthy()
 })
+
+test('externalDependencies should prevent package from being hoisted to the root', async () => {
+  prepareEmpty()
+
+  const externalDependencies = new Set(['ms'])
+  await install({
+    dependencies: {
+      send: '0.17.2',
+    },
+  }, await testDefaults({
+    nodeLinker: 'hoisted',
+    externalDependencies,
+  }))
+
+  expect(fs.existsSync('node_modules/ms')).toBeFalsy()
+  expect(fs.existsSync('node_modules/send/node_modules/ms')).toBeTruthy()
+})

pkg-manager/headless/src/index.ts

@@ -109,6 +109,7 @@ export interface HeadlessOptions {
   extraNodePaths?: string[]
   preferSymlinkedExecutables?: boolean
   hoistingLimits?: HoistingLimits
+  externalDependencies?: Set<string>
   ignoreDepScripts: boolean
   ignoreScripts: boolean
   ignorePackageManifest?: boolean

pkg-manager/headless/src/lockfileToHoistedDepGraph.ts

@@ -29,6 +29,7 @@ export interface LockfileToHoistedDepGraphOptions {
   engineStrict: boolean
   force: boolean
   hoistingLimits?: HoistingLimits
+  externalDependencies?: Set<string>
   importerIds: string[]
   include: IncludedDependencies
   lockfileDir: string
@@ -64,7 +65,7 @@ async function _lockfileToHoistedDepGraph (
   lockfile: Lockfile,
   opts: LockfileToHoistedDepGraphOptions
 ): Promise<Omit<LockfileToDepGraphResult, 'prevGraph'>> {
-  const tree = hoist(lockfile, { hoistingLimits: opts.hoistingLimits })
+  const tree = hoist(lockfile, { hoistingLimits: opts.hoistingLimits, externalDependencies: opts.externalDependencies })
   const graph: DependenciesGraph = {}
   const modulesDir = path.join(opts.lockfileDir, 'node_modules')
   const fetchDepsOpts = {

pkg-manager/real-hoist/src/index.ts

@@ -14,6 +14,9 @@ export function hoist (
   lockfile: Lockfile,
   opts?: {
     hoistingLimits?: HoistingLimits
+    // This option was added for Bit CLI in order to prevent pnpm from overwriting dependencies linked by Bit.
+    // However, in the future it might be useful to use it in pnpm for skipping any dependencies added by external tools.
+    externalDependencies?: Set<string>
   }
 ): HoisterResult {
   const nodes = new Map<string, HoisterTree>()
@@ -27,6 +30,13 @@ export function hoist (
       ...lockfile.importers['.']?.dependencies,
       ...lockfile.importers['.']?.devDependencies,
       ...lockfile.importers['.']?.optionalDependencies,
+      ...(Array.from(opts?.externalDependencies ?? [])).reduce((acc, dep) => {
+        // It doesn't matter what version spec is used here.
+        // This dependency will be removed from the tree anyway.
+        // It is only needed to prevent the hoister from hoisting deps with this name to the root of node_modules.
+        acc[dep] = 'link:'
+        return acc
+      }, {}),
     }),
   }
   for (const [importerId, importer] of Object.entries(lockfile.importers)) {
@@ -46,7 +56,15 @@ export function hoist (
     node.dependencies.add(importerNode)
   }
 
-  return _hoist(node, opts)
+  const hoisterResult = _hoist(node, opts)
+  if (opts?.externalDependencies) {
+    for (const hoistedDep of hoisterResult.dependencies.values()) {
+      if (opts.externalDependencies.has(hoistedDep.name)) {
+        hoisterResult.dependencies.delete(hoistedDep)
+      }
+    }
+  }
+  return hoisterResult
 }
 
 function toTree (nodes: Map<string, HoisterTree>, lockfile: Lockfile, deps: Record<string, string>): Set<HoisterTree> {