Fix rounding in Number.prototype.toFixed (#3747)

Fixes #3741.

JerryScript-DCO-1.0-Signed-off-by: Dániel Bátyai dbatyai@inf.u-szeged.hu

tests/jerry/number-prototype-to-fixed.js

@@ -63,3 +63,35 @@ try {
 } catch (e) {
     assert(e instanceof RangeError)
 }
+
+assert ((0.5).toFixed(0) === "1");
+assert ((1.5).toFixed(0) === "2");
+assert ((12.5).toFixed(0) === "13");
+assert ((123.5).toFixed(0) === "124");
+assert ((1234.5).toFixed(0) === "1235");
+assert ((0.567).toFixed(0) === "1");
+assert ((1.567).toFixed(0) === "2");
+assert ((12.567).toFixed(0) === "13");
+assert ((123.567).toFixed(0) === "124");
+assert ((1234.567).toFixed(0) === "1235");
+
+assert ((1.2567).toFixed(0) === "1");
+assert ((1.2567).toFixed(1) === "1.3");
+assert ((1.2567).toFixed(2) === "1.26");
+assert ((1.2567).toFixed(3) === "1.257");
+assert ((1.2567).toFixed(4) === "1.2567");
+assert ((1.2567).toFixed(5) === "1.25670");
+
+assert ((12.3567).toFixed(0) === "12");
+assert ((12.3567).toFixed(1) === "12.4");
+assert ((12.3567).toFixed(2) === "12.36");
+assert ((12.3567).toFixed(3) === "12.357");
+assert ((12.3567).toFixed(4) === "12.3567");
+assert ((12.3567).toFixed(5) === "12.35670");
+
+assert ((123.4567).toFixed(0) === "123");
+assert ((123.4567).toFixed(1) === "123.5");
+assert ((123.4567).toFixed(2) === "123.46");
+assert ((123.4567).toFixed(3) === "123.457");
+assert ((123.4567).toFixed(4) === "123.4567");
+assert ((123.4567).toFixed(5) === "123.45670");