perf: don't duplicate leaf nodes in dependenciesTree (#8751)

.changeset/hot-numbers-live.md

@@ -0,0 +1,5 @@
+---
+"@pnpm/resolve-dependencies": patch
+---
+
+Don't duplicate leaf nodes in dependenciesTree.

pkg-manager/resolve-dependencies/src/resolveDependencies.ts

@@ -219,6 +219,7 @@ export type PeerDependencies = Record<string, PeerDependency>
 
 export interface ResolvedPackage {
   id: PkgResolutionId
+  isLeaf: boolean
   resolution: Resolution
   prod: boolean
   dev: boolean
@@ -1609,6 +1610,7 @@ function getResolvedPackage (
       os: options.pkg.os,
       libc: options.pkg.libc,
     },
+    isLeaf: pkgIsLeaf(options.pkg),
     pkgIdWithPatchHash: options.pkgIdWithPatchHash,
     dev: options.wantedDependency.dev,
     fetching: options.pkgResponse.fetching!,

pkg-manager/resolve-dependencies/src/resolveDependencyTree.ts

@@ -305,6 +305,10 @@ function buildTree (
     if (parentIdsContainSequence(parentIds, parentId, child.id) || parentId === child.id) {
       continue
     }
+    if (ctx.resolvedPkgsById[child.id].isLeaf) {
+      childrenNodeIds[child.alias] = child.id as unknown as NodeId
+      continue
+    }
     const childNodeId = nextNodeId()
     childrenNodeIds[child.alias] = childNodeId
     installable = installable || !ctx.skipped.has(child.id)