Add new acceptance test scenario: 046

examples/acceptance_tests/046/lib/tests.ak

@@ -0,0 +1,9 @@
+test sort_by_1() {
+  let xs = [[4, 3, 2, 1], [2, 3, 4, 5]]
+  when xs is {
+    [[], ys] -> True
+    [xs, []] -> True
+    [[x, ..xs2], [y, ..ys2]] -> True
+    _ -> True
+  }
+}