fix(nm): takes into account scoped packages during syncing tree with disk

.yarn/versions/9aaf86c6.yml

@@ -0,0 +1,23 @@
+releases:
+  "@yarnpkg/cli": patch
+  "@yarnpkg/plugin-nm": patch
+
+declined:
+  - "@yarnpkg/plugin-compat"
+  - "@yarnpkg/plugin-constraints"
+  - "@yarnpkg/plugin-dlx"
+  - "@yarnpkg/plugin-essentials"
+  - "@yarnpkg/plugin-init"
+  - "@yarnpkg/plugin-interactive-tools"
+  - "@yarnpkg/plugin-npm-cli"
+  - "@yarnpkg/plugin-pack"
+  - "@yarnpkg/plugin-patch"
+  - "@yarnpkg/plugin-pnp"
+  - "@yarnpkg/plugin-pnpm"
+  - "@yarnpkg/plugin-stage"
+  - "@yarnpkg/plugin-typescript"
+  - "@yarnpkg/plugin-version"
+  - "@yarnpkg/plugin-workspace-tools"
+  - "@yarnpkg/builder"
+  - "@yarnpkg/core"
+  - "@yarnpkg/doctor"

packages/acceptance-tests/pkg-tests-specs/sources/node-modules.test.ts

@@ -1649,6 +1649,32 @@ describe(`Node_Modules`, () => {
     ),
   );
 
+  it(`should only reinstall scoped dependencies deleted by the user on the next install`,
+    makeTemporaryEnv(
+      {
+        dependencies: {
+          [`@types/no-deps`]: `1.0.0`,
+          [`@types/is-number`]: `1.0.0`,
+        },
+      },
+      {
+        nodeLinker: `node-modules`,
+      },
+      async ({path, run}) => {
+        await run(`install`);
+
+        await xfs.removePromise(`${path}/node_modules/@types/is-number` as PortablePath);
+        const inode = (await xfs.statPromise(`${path}/node_modules/@types/no-deps/package.json` as PortablePath)).ino;
+
+        await run(`install`);
+        const nextInode = (await xfs.statPromise(`${path}/node_modules/@types/no-deps/package.json` as PortablePath)).ino;
+
+        await expect(xfs.existsPromise(`${path}/node_modules/@types/is-number` as PortablePath));
+        expect(nextInode).toEqual(inode);
+      },
+    ),
+  );
+
   it(`should support portals to external workspaces`,
     makeTemporaryEnv(
       {

packages/plugin-nm/sources/NodeModulesLinker.ts

@@ -842,12 +842,12 @@ function syncPreinstallStateWithDisk(locationTree: LocationTree, binSymlinks: Bi
   const locatorLocations = new Map();
   let installChangedByUser = false;
 
-  const syncNodeWithDisk = (parentPath: PortablePath, entry: Filename, parentNode: LocationNode, refinedNode: LocationNode, nodeModulesDiskEntries: Set<Filename>) => {
+  const syncNodeWithDisk = (parentPath: PortablePath, entry: Filename, parentNode: LocationNode, refinedNode: LocationNode, parentDiskEntries: Set<Filename>) => {
     let doesExistOnDisk = true;
     const entryPath = ppath.join(parentPath, entry);
-    let childNodeModulesDiskEntries = new Set<Filename>();
+    let childDiskEntries = new Set<Filename>();
 
-    if (entry === NODE_MODULES) {
+    if (entry === NODE_MODULES || entry.startsWith(`@`)) {
       let stats;
       try {
         stats = xfs.statSync(entryPath);
@@ -860,9 +860,9 @@ function syncPreinstallStateWithDisk(locationTree: LocationTree, binSymlinks: Bi
         installChangedByUser = true;
       } else if (stats.mtimeMs > stateMtimeMs) {
         installChangedByUser = true;
-        childNodeModulesDiskEntries = new Set(xfs.readdirSync(entryPath));
+        childDiskEntries = new Set(xfs.readdirSync(entryPath));
       } else {
-        childNodeModulesDiskEntries = new Set(parentNode.children.get(NODE_MODULES)!.children.keys());
+        childDiskEntries = new Set(parentNode.children.get(entry)!.children.keys());
       }
 
       const binarySymlinks = binSymlinks.get(parentPath);
@@ -893,7 +893,7 @@ function syncPreinstallStateWithDisk(locationTree: LocationTree, binSymlinks: Bi
         }
       }
     } else {
-      doesExistOnDisk = nodeModulesDiskEntries.has(entry);
+      doesExistOnDisk = parentDiskEntries.has(entry);
     }
 
     const node = parentNode.children.get(entry)!;
@@ -908,7 +908,7 @@ function syncPreinstallStateWithDisk(locationTree: LocationTree, binSymlinks: Bi
       }
 
       for (const childEntry of node.children.keys()) {
-        syncNodeWithDisk(entryPath, childEntry, node, childRefinedNode, childNodeModulesDiskEntries);
+        syncNodeWithDisk(entryPath, childEntry, node, childRefinedNode, childDiskEntries);
       }
     } else if (node.locator) {
       project.storedBuildState.delete(structUtils.parseLocator(node.locator).locatorHash);