From bb11214abff3b16ae98f0e7c263940f386afe349 Mon Sep 17 00:00:00 2001
From: Mate Dabis <mdabis@inf.u-szeged.hu>
Date: Thu, 10 Jan 2019 09:40:16 +0100
Subject: [PATCH] Increase test coverage: Array.prototype reverse

Branch coverage:
Before: 28/38
After: 37//38

Also found an opportunity to optimize, the second condition was not needed
in that else if branch, as if the code reaches there, it cant be false.

JerryScript-DCO-1.0-Signed-off-by: Mate Dabis mdabis@inf.u-szeged.hu
---
 .../ecma-builtin-array-prototype.c            |  2 +-
 tests/jerry/array-prototype-reverse.js        | 96 +++++++++++++++++++
 2 files changed, 97 insertions(+), 1 deletion(-)

diff --git a/jerry-core/ecma/builtin-objects/ecma-builtin-array-prototype.c b/jerry-core/ecma/builtin-objects/ecma-builtin-array-prototype.c
index 04d093b454..a7c8444066 100644
--- a/jerry-core/ecma/builtin-objects/ecma-builtin-array-prototype.c
+++ b/jerry-core/ecma/builtin-objects/ecma-builtin-array-prototype.c
@@ -642,7 +642,7 @@ ecma_builtin_array_prototype_object_reverse (ecma_value_t this_arg) /**< this ar
       ECMA_FINALIZE (put_value);
     }
     /* 6.j */
-    else if (lower_exist && !upper_exist)
+    else if (lower_exist)
     {
       ECMA_TRY_CATCH (del_value, ecma_op_object_delete (obj_p, lower_str_p, true), ret_value);
       ECMA_TRY_CATCH (put_value, ecma_op_object_put (obj_p, upper_str_p, lower_value, true), ret_value);
diff --git a/tests/jerry/array-prototype-reverse.js b/tests/jerry/array-prototype-reverse.js
index 69be5af418..9f044df97d 100644
--- a/tests/jerry/array-prototype-reverse.js
+++ b/tests/jerry/array-prototype-reverse.js
@@ -43,3 +43,99 @@ try {
   assert(e.message === "foo");
   assert(e instanceof ReferenceError);
 }
+
+/* ES v5.1 15.4.4.8.1
+   Checking behavior when null is passed to the function */
+try {
+  Array.prototype.reverse.call(null);
+  assert(false);
+} catch (e) {
+  assert(e instanceof TypeError);
+}
+
+/* ES v5.1 15.4.4.8.3.
+   Checking behavior when length is not a number */
+try {
+  var o = {};
+  Object.defineProperty(o, 'toString', { 'get' : function () { throw new ReferenceError ("foo"); } });
+  var a = { length : o};
+  Array.prototype.reverse.call(a);
+  assert(false);
+} catch (e) {
+  assert(e instanceof ReferenceError);
+  assert(e.message == "foo");
+}
+
+/* ES v5.1 15.4.4.8.6.e.
+   Checking behavior when unable to get the last element */
+var obj = { reverse : Array.prototype.reverse, length : 4 };
+Object.defineProperty(obj, '3', { 'get' : function () {throw new ReferenceError ("foo"); } });
+
+try {
+  obj.reverse();
+  assert(false);
+} catch (e) {
+  assert(e.message === "foo");
+  assert(e instanceof ReferenceError);
+}
+
+/* ES v5.1 15.4.4.8.6.h.i.
+   Checking behavior when first 3 elements are not writable */
+try {
+  var arr = [0, 1, 2, 3, 4, 5, 6,,,,,,,,,0, 1, 2, 3, 4, 5, 6];
+  Object.defineProperty(arr, '0', { writable : false });
+  Object.defineProperty(arr, '1', { writable : false });
+  Object.defineProperty(arr, '2', { writable : false });
+  Array.prototype.reverse.call(arr);
+  assert(false);
+} catch (e) {
+  assert(e instanceof TypeError);
+}
+
+/* ES v5.1 15.4.4.8.6.h.ii.
+   Checking behavior when last 3 elements are not writable */
+try {
+  var arr = [0, 1, 2, 3, 4, 5, 6,,,,,,,,,0, 1, 2, 3, 4, 5, 6];
+  Object.defineProperty(arr, '20', { writable : false });
+  Object.defineProperty(arr, '21', { writable : false });
+  Object.defineProperty(arr, '22', { writable : false });
+  Array.prototype.reverse.call(arr);
+  assert(false);
+} catch (e) {
+  assert(e instanceof TypeError);
+}
+
+/* ES v5.1 15.4.4.8.6.i.i.
+   Checking behavior when first elements do not exist and the array is freezed */
+try {
+  var arr = [,,,,,,,,,,,,,,,,0, 1, 2, 3, 4, 5, 6];
+  arr = Object.freeze(arr);
+  Array.prototype.reverse.call(arr);
+  assert(false);
+} catch (e) {
+  assert(e instanceof TypeError);
+}
+
+/* ES v5.1 15.4.4.8.6.i.ii.
+   Checking behavior when unable to get the first 2 elements */
+var obj = { reverse : Array.prototype.reverse, length : 4 };
+Object.defineProperty(obj, '2', { value : 0 });
+Object.defineProperty(obj, '3', { value : 0 });
+try {
+  obj.reverse();
+  assert(false);
+} catch (e) {
+  assert(e instanceof TypeError);
+}
+
+/* ES v5.1 15.4.4.8.6.j.i.
+   Checking behavior when unable to get the last 2 elements */
+var obj = { reverse : Array.prototype.reverse, length : 4 };
+Object.defineProperty(obj, '0', { value : 0 });
+Object.defineProperty(obj, '1', { value : 0 });
+try {
+  obj.reverse();
+  assert(false);
+} catch (e) {
+  assert(e instanceof TypeError);
+}