javascriptdata
diff --git a/‎src/danfojs-browser/tests/core/frame.test.js
Lines changed: 11 additions & 0 deletions b/‎src/danfojs-browser/tests/core/frame.test.js
Lines changed: 11 additions & 0 deletions
diff --git a/‎src/danfojs-browser/tests/core/series.test.js
Lines changed: 39 additions & 0 deletions b/‎src/danfojs-browser/tests/core/series.test.js
Lines changed: 39 additions & 0 deletions
@@ -1319,6 +1319,17 @@ describe("DataFrame", function () {
         [ 6, 9 ] ];
       assert.deepEqual(df.sortValues("A", { "ascending": true }).values, expected);
     });
+
+    it("sort index in descending order and retains index", function () {
+      let data = [ [ 0, 2, 4, "b" ],
+        [ 360, 180, 360, "a" ],
+        [ 2, 4, 6, "c" ] ];
+
+      let df = new dfd.DataFrame(data, { "columns": [ "col1", "col2", "col3", "col4" ], index: [ "b", "a", "c" ] });
+      let df2 = df.sortIndex({ ascending: false });
+      let rslt = [ "c", "b", "a" ];
+      assert.deepEqual(df2.index, rslt);
+    });
   });
 
   describe("copy", function () {
 
@@ -688,6 +688,45 @@ describe("Series Functions", () => {
       const sortedSf = sf.sortValues({ ascending: false });
       assert.deepEqual(sortedSf.values, result);
     });
+
+    it("Index is retained after sort (ascending=true)", function () {
+      let index = [ "apple", "banana", "orange", "grape" ];
+      let value = [ 3, 6, 2, 9 ];
+
+      let sf = new dfd.Series(value, { index });
+      sf.sortValues().print();
+      const expectedValues = [ 2, 3, 6, 9 ];
+      const expectedIndex = [ "orange", "apple", "banana", "grape" ];
+      const sortedSf = sf.sortValues();
+      assert.deepEqual(sortedSf.values, expectedValues);
+      assert.deepEqual(sortedSf.index, expectedIndex);
+    });
+    it("Index is retained after sort (ascending=false)", function () {
+      let index = [ "apple", "banana", "orange", "grape" ];
+      let value = [ 3, 6, 2, 9 ];
+
+      let sf = new dfd.Series(value, { index });
+      sf.sortValues().print();
+      const expectedValues = [ 9, 6, 3, 2 ];
+      const expectedIndex = [ "grape", "banana", "apple", "orange" ];
+      const sortedSf = sf.sortValues({ ascending: false });
+      assert.deepEqual(sortedSf.values, expectedValues);
+      assert.deepEqual(sortedSf.index, expectedIndex);
+    });
+
+    it("Index is retained after inplace sort (ascending=false)", function () {
+      let index = [ "apple", "banana", "orange", "grape" ];
+      let value = [ 3, 6, 2, 9 ];
+
+      let sf = new dfd.Series(value, { index });
+      sf.sortValues().print();
+      const expectedValues = [ 9, 6, 3, 2 ];
+      const expectedIndex = [ "grape", "banana", "apple", "orange" ];
+      sf.sortValues({ ascending: false, inplace: true });
+      assert.deepEqual(sf.values, expectedValues);
+      assert.deepEqual(sf.index, expectedIndex);
+    });
+
   });
 
   describe("describe", function () {