Runtime: don't use double equal (part 2)

Author: hhugo

lib/tests/test_poly_compare.ml

@@ -36,7 +36,7 @@ let%expect_test "poly equal neg" =
 let%expect_test "poly compare" =
   let obj1 = Js.Unsafe.obj [| "a", Js.Unsafe.inject 0 |] in
   let obj2 = Js.Unsafe.obj [| "a", Js.Unsafe.inject 0 |] in
-  (match List.sort compare [ obj1; obj1 ] with
+  (match List.sort compare [ obj1; obj2 ] with
   | [ a; b ] ->
       if a == obj1 && b == obj2
       then print_endline "preserve"
@@ -98,6 +98,15 @@ let%expect_test "object comparison" =
   assert (compare s1 s2 = 1);
   assert (compare s2 s1 = 1)
 
+let%expect_test "null/undefined comparison" =
+  let s1 = Pack (Js.Unsafe.js_expr "undefined") in
+  let s2 = Pack (Js.Unsafe.js_expr "null") in
+  assert (s1 <> s2);
+  assert (s1 = s1);
+  assert (compare s1 s1 = 0);
+  assert (compare s1 s2 = 1);
+  assert (compare s2 s1 = 1)
+
 let%expect_test "poly compare" =
   let l =
     [ Pack (object end)
@@ -119,10 +128,11 @@ let%expect_test "poly compare" =
     3
     2
     0
-    6
     7
+    6
     5
-    4 |}];
+    4
+    |}];
   let l' = List.sort (fun (_, a) (_, b) -> compare a b) (List.rev l) in
   let l'' = List.sort (fun (_, a) (_, b) -> compare a b) (List.rev l') in
   List.iter (fun (i, _) -> Printf.printf "%d\n" i) l';
@@ -134,8 +144,9 @@ let%expect_test "poly compare" =
     0
     4
     5
+    6
     7
-    6 |}];
+    |}];
   List.iter (fun (i, _) -> Printf.printf "%d\n" i) l'';
   print_endline "";
   [%expect {|

runtime/compare.js

@@ -109,15 +109,16 @@ function caml_compare_val(a, b, total) {
         }
         return tag_a < tag_b ? -1 : 1;
       }
+      // tag_a = tag_b
       switch (tag_a) {
         // 246: Lazy_tag handled bellow
         case 247: // Closure_tag
           // Cannot happen
           caml_invalid_argument("compare: functional value");
           break;
         case 248: // Object
-          var x = caml_int_compare(a[2], b[2]);
-          if (x !== 0) return x | 0;
+          var x = caml_int_compare(a[2], b[2]) | 0;
+          if (x !== 0) return x;
           break;
         case 249: // Infix
           // Cannot happen
@@ -132,8 +133,8 @@ function caml_compare_val(a, b, total) {
           break;
         case 252: // OCaml bytes
           if (a !== b) {
-            var x = caml_bytes_compare(a, b);
-            if (x !== 0) return x | 0;
+            var x = caml_bytes_compare(a, b) | 0;
+            if (x !== 0) return x;
           }
           break;
         case 253: // Double_tag
@@ -204,20 +205,15 @@ function caml_compare_val(a, b, total) {
           // - if a and b are strings, apply lexicographic comparison
           // - if a or b are not strings, convert a and b to number
           //   and apply standard comparison
-          //
-          // Exception: `!=` will not coerce/convert if both a and b are objects
           if (a < b) return -1;
           if (a > b) return 1;
           if (a !== b) {
-            if (!total) return Number.NaN;
-            if (!Number.isNaN(a)) return 1;
-            if (!Number.isNaN(b)) return -1;
+            return total ? 1 : Number.NaN;
           }
           break;
         case 1251: // JavaScript Symbol, no ordering.
           if (a !== b) {
-            if (!total) return Number.NaN;
-            return 1;
+            return total ? 1 : Number.NaN;
           }
           break;
         case 1252: // ocaml strings