Always keep __name__ field in indexes when list indexes (#9160)

* Always keep the __name__ field in index when list indexes

* fix unit tests

* teach indexMatchesSpec to understand __name__ normalization of standard database

* update CHANGELOG and adapt changes to unit tests

---------

Co-authored-by: Joe Hanley <[email protected]>

Author: ninjaAB-5

CHANGELOG.md

@@ -1,3 +1,4 @@
+- Fixed an issue with deploying indexes to Firestore Enterprise edition databases where explicit `__name__` fields could be incorrectly handled.
 - The `experimental:mcp` command has been renamed to `mcp`. The old name is now an alias.
 - `firebase_update_environment` MCP tool supports accepting Gemini in Firebase Terms of Service.
 - Fixed a bug when `firebase init dataconnect` failed to create a React app when launched from VS Code extension (#9171).

src/firestore/api.ts

@@ -21,28 +21,26 @@ export class FirestoreApi {
   printer = new PrettyPrint();
 
   /**
-   * Process indexes by filtering out implicit __name__ fields with ASCENDING order.
-   * Keeps explicit __name__ fields with DESCENDING order.
-   * @param indexes Array of indexes to process
-   * @return Processed array of indexes with filtered fields
+   * Process indexes by appending the implicit __name__ fields with default order for STANDARD edition database.
+   * No-op if exists __name__ field at the end.
+   * No-op is ENTERPRISE edition databases.
+   * @param index Spec index to process
+   * @return Processed spec index with potential additional __name__ suffix
    */
-  public static processIndexes(indexes: types.Index[]): types.Index[] {
-    return indexes.map((index: types.Index): types.Index => {
-      // Per https://firebase.google.com/docs/firestore/query-data/index-overview#default_ordering_and_the_name_field
-      // this matches the direction of the last non-name field in the index.
-      let fields = index.fields;
-      const lastField = index.fields?.[index.fields.length - 1];
-      if (lastField?.fieldPath === "__name__") {
-        const defaultDirection = index.fields?.[index.fields.length - 2]?.order;
-        if (lastField?.order === defaultDirection) {
-          fields = fields.slice(0, -1);
-        }
-      }
-      return {
-        ...index,
-        fields,
-      };
-    });
+  public static processIndex(index: Spec.Index): Spec.Index {
+    // Per https://firebase.google.com/docs/firestore/query-data/index-overview#default_ordering_and_the_name_field
+    // this matches the direction of the last non-name field in the index.
+    const fields = index.fields;
+    const lastField = index.fields?.[index.fields.length - 1];
+    if (lastField?.fieldPath !== "__name__") {
+      const defaultDirection = index.fields?.[index.fields.length - 1]?.order;
+      const nameSuffix = { fieldPath: "__name__", order: defaultDirection } as types.IndexField;
+      fields.push(nameSuffix);
+    }
+    return {
+      ...index,
+      fields,
+    };
   }
 
   /**
@@ -212,7 +210,7 @@ export class FirestoreApi {
       return [];
     }
 
-    return FirestoreApi.processIndexes(indexes);
+    return indexes;
   }
 
   /**
@@ -559,14 +557,19 @@ export class FirestoreApi {
 
     // TODO(b/439901837): Compare `unique` index configuration when it's supported.
 
-    if (index.fields.length !== spec.fields.length) {
+    let specIdx = spec;
+    if (edition === DatabaseEdition.STANDARD) {
+      specIdx = FirestoreApi.processIndex(specIdx);
+    }
+
+    if (index.fields.length !== specIdx.fields.length) {
       return false;
     }
 
     let i = 0;
     while (i < index.fields.length) {
       const iField = index.fields[i];
-      const sField = spec.fields[i];
+      const sField = specIdx.fields[i];
 
       if (iField.fieldPath !== sField.fieldPath) {
         return false;