test: speed up mongo test resets by preserving indexes (#14861)

MongoDB test resets (clearAndSeedEverything) were taking 4-5s because we
were dropping the entire database and recreating indexes every time. Now
we just delete documents (like Postgres does), which preserves indexes
and makes consecutive test runs much faster.

Author: AlessioGr

test/helpers/reset.ts

@@ -10,7 +10,17 @@ export async function resetDB(_payload: Payload, collectionSlugs: string[]) {
     if (!firstCollectionSlug?.length) {
       throw new Error('No collection slugs provided to reset the database.')
     }
-    await _payload.db.collections[firstCollectionSlug]?.db.dropDatabase()
+
+    // Delete all documents from each collection instead of dropping the database.
+    // This preserves indexes and is much faster for consecutive test runs.
+    const mongooseCollections = _payload.db.collections[firstCollectionSlug]?.db.collections
+    if (mongooseCollections) {
+      await Promise.all(
+        Object.values(mongooseCollections).map(async (collection: any) => {
+          await collection.deleteMany({})
+        }),
+      )
+    }
   } else if ('drizzle' in _payload.db) {
     const db = _payload.db as unknown as DrizzleAdapter
 

test/helpers/seed.ts

@@ -4,7 +4,6 @@ import path from 'path'
 import { type Payload } from 'payload'
 
 import { isErrorWithCode } from './isErrorWithCode.js'
-import { isMongoose } from './isMongoose.js'
 import { resetDB } from './reset.js'
 import { createSnapshot, dbSnapshot, restoreFromSnapshot, uploadsDirCache } from './snapshot.js'
 
@@ -120,33 +119,6 @@ export async function seedDB({
     restored = true
   }
 
-  /**
-   *  Mongoose: Re-create indexes
-   *  Postgres: No need for any action here, since we only delete the table data and no schemas
-   */
-  // Dropping the db breaks indexes (on mongoose - did not test extensively on postgres yet), so we recreate them here
-  try {
-    if (isMongoose(_payload)) {
-      await Promise.all([
-        ...collectionSlugs
-          .filter(
-            (collectionSlug) =>
-              ['payload-migrations', 'payload-preferences', 'payload-locked-documents'].indexOf(
-                collectionSlug,
-              ) === -1,
-          )
-          .map(async (collectionSlug) => {
-            await _payload.db.collections[collectionSlug]?.createIndexes({
-              // Blocks writes (doesn't matter here) but faster
-              background: false,
-            })
-          }),
-      ])
-    }
-  } catch (e) {
-    console.error('Error in operation (re-creating indexes):', e)
-  }
-
   /**
    * If a snapshot was restored, we don't need to seed the database
    */