[rush] Fix(#5552): sort additionalFilesForOperation for hashing (#5629)

* [rush] Fix(#5552): sort additionalFilesForOperation for hashing

Fixes #5552: sort additionalFilesForOperation to produce a stable hash for caching

* Update common/changes/@microsoft/rush/eric.prestemon-fix-5552_2026-02-18-01-11.json

Co-authored-by: Ian Clanton-Thuon <iclanton@users.noreply.github.com>

---------

Co-authored-by: Eric Prestemon <eric.prestemon@users.noreply.github.com>
Co-authored-by: Ian Clanton-Thuon <iclanton@users.noreply.github.com>

Author: 3 people

common/changes/@microsoft/rush/eric.prestemon-fix-5552_2026-02-18-01-11.json

@@ -0,0 +1,10 @@
+{
+  "changes": [
+    {
+      "packageName": "@microsoft/rush",
+      "comment": "Sort the `additionalFilesForOperation` property in operation settings entries in projects' `config/rush-project.json` files before computing operation hashes to produce a stable hash for caching.",
+      "type": "none"
+    }
+  ],
+  "packageName": "@microsoft/rush"
+}

libraries/rush-lib/src/logic/incremental/InputsSnapshot.ts

@@ -334,7 +334,9 @@ export class InputsSnapshot implements IInputsSnapshot {
         const additionalFilesForOperation: ReadonlySet<string> | undefined =
           record.additionalFilesByOperationName?.get(operationName);
         if (additionalFilesForOperation) {
-          for (const [filePath, hash] of this._resolveHashes(additionalFilesForOperation)) {
+          // Sort the additional files to ensure deterministic hash computation
+          const sortedAdditionalFiles: string[] = Array.from(additionalFilesForOperation).sort();
+          for (const [filePath, hash] of this._resolveHashes(sortedAdditionalFiles)) {
             hashes.set(filePath, hash);
           }
         }