1 files changed, 43 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/warp/scalar-replace-rest-construct-array.js b/js/src/jit-test/tests/warp/scalar-replace-rest-construct-array.js
new file mode 100644
index 0000000000..e2c0c5b354
--- /dev/null
+++ b/js/src/jit-test/tests/warp/scalar-replace-rest-construct-array.js
@@ -0,0 +1,43 @@
+// Prevent GC from cancelling/discarding Ion compilations.
+gczeal(0);
+
+// Create a fresh set of functions for each argument count to avoid type pollution.
+function makeTest(count) {
+  var args = Array(count).fill(0).join(",");
+
+  return Function(`
+    class Base {
+      constructor() {
+        this.count = arguments.length;
+      }
+    }
+  
+    class C extends Base {
+      constructor(...args) {
+        assertRecoveredOnBailout(args, true);
+        return super(...args);
+      }
+    }
+
+    function test() {
+      // Ensure |C| isn't inlined into its caller.
+      with ({});
+
+      for (let i = 0; i < 1000; ++i) {
+        let obj = new C(${args});
+        assertEq(obj.count, ${count});
+      }
+    }
+
+    return test;
+  `)();
+}
+
+// Inline rest arguments are limited to 14 elements, cf.
+// gc::CanUseFixedElementsForArray() in WarpBuilder::build_Rest().
+// There isn't such limit when the function isn't inlined.
+const maxRestArgs = 20;
+
+for (let i = 0; i <= maxRestArgs; ++i) {
+  makeTest(i)();
+}