fix: saving multiple versions (#918)

* test: saving multiple versions with unique fields

* fix: saving multiple versions with unique fields

Version schemas were getting produced with uniqueness constraints which
caused updates to likely fail because each successive version would
potentially reuse unchanged unique key-values (particularly ident keys
like slug) from previous versions.

This was due to `mongoose.buildSchema` not respecting buildSchemaOptions.disableUnique.

This regression was introduced with the fix at commit c175476e.

* test: eslint fix

Co-authored-by: Dan Ribbens <dan.ribbens@gmail.com>

src/mongoose/buildSchema.ts

@@ -80,7 +80,7 @@ const buildSchema = (config: SanitizedConfig, configFields: Field[], buildSchema
       if (config.indexSortableFields && !buildSchemaOptions.global && !field.index && !field.hidden && sortableFieldTypes.indexOf(field.type) > -1 && fieldAffectsData(field)) {
         indexFields.push({ index: { [field.name]: 1 } });
       } else if (field.unique && fieldAffectsData(field)) {
-        indexFields.push({ index: { [field.name]: 1 }, options: { unique: true, sparse: field.localized || false } });
+        indexFields.push({ index: { [field.name]: 1 }, options: { unique: !buildSchemaOptions.disableUnique, sparse: field.localized || false } });
       } else if (field.index && fieldAffectsData(field)) {
         indexFields.push({ index: { [field.name]: 1 } });
       }

test/versions/int.spec.ts

@@ -62,7 +62,7 @@ describe('Versions', () => {
 
         collectionLocalPostID = autosavePost.id;
 
-        const updatedPost = await payload.update<any>({
+        const updatedPost = await payload.update({
           id: collectionLocalPostID,
           collection,
           data: {
@@ -82,6 +82,35 @@ describe('Versions', () => {
         expect(collectionLocalVersionID).toBeDefined();
       });
 
+      it('should allow saving multiple versions of models with unique fields', async () => {
+        const autosavePost = await payload.create({
+          collection,
+          data: {
+            title: 'unique unchanging title',
+            description: 'description 1',
+          },
+        });
+
+        await payload.update({
+          id: autosavePost.id,
+          collection,
+          data: {
+            description: 'description 2',
+          },
+        });
+        const finalDescription = 'final description';
+
+        const secondUpdate = await payload.update({
+          id: autosavePost.id,
+          collection,
+          data: {
+            description: finalDescription,
+          },
+        });
+
+        expect(secondUpdate.description).toBe(finalDescription);
+      });
+
       it('should allow a version to be retrieved by ID', async () => {
         const version = await payload.findVersionByID({
           collection,