fix: add support for descending sorting of full text search

CHANGELOG.md

@@ -152,6 +152,7 @@ ___
 - Refactor: uniform issue templates across repos (Manuel Trezza) [#7528](https://github.com/parse-community/parse-server/pull/7528)
 - ci: bump ci environment (Manuel Trezza) [#7539](https://github.com/parse-community/parse-server/pull/7539)
 - CI now pushes docker images to Docker Hub (Corey Baker) [#7548](https://github.com/parse-community/parse-server/pull/7548)
+- Allow setting descending sort to full text queries (dblythy) [#7496](https://github.com/parse-community/parse-server/pull/7496)
 - Allow cloud string for ES modules (Daniel Blyth) [#7560](https://github.com/parse-community/parse-server/pull/7560)
 - docs: Introduce deprecation ID for reference in comments and online search (Manuel Trezza) [#7562](https://github.com/parse-community/parse-server/pull/7562)
 

spec/ParseQuery.FullTextSearch.spec.js

@@ -120,6 +120,19 @@ describe('Parse.Query Full Text Search testing', () => {
       }, done.fail);
   });
 
+  it('fulltext descending by $score', async () => {
+    await fullTextHelper();
+    const query = new Parse.Query('TestObject');
+    query.fullText('subject', 'coffee');
+    query.descending('$score');
+    query.select('$score');
+    const results = await query.find();
+    expect(results.length).toBe(3);
+    expect(results[0].get('score'));
+    expect(results[1].get('score'));
+    expect(results[2].get('score'));
+  });
+
   it('fullTextSearch: $language', done => {
     fullTextHelper()
       .then(() => {

src/RestQuery.js

@@ -143,7 +143,7 @@ function RestQuery(
         var fields = restOptions.order.split(',');
         this.findOptions.sort = fields.reduce((sortMap, field) => {
           field = field.trim();
-          if (field === '$score') {
+          if (field === '$score' || field === '-$score') {
             sortMap.score = { $meta: 'textScore' };
           } else if (field[0] == '-') {
             sortMap[field.slice(1)] = -1;