type coercion harness utilities

1 files changed, 30 insertions, 0 deletions

diff --git a/test/built-ins/String/prototype/indexOf/position-tointeger.js b/test/built-ins/String/prototype/indexOf/position-tointeger.js
new file mode 100644
index 000000000..749968274
--- /dev/null
+++ b/test/built-ins/String/prototype/indexOf/position-tointeger.js
@@ -0,0 +1,30 @@
+// Copyright (C) 2017 Josh Wolfe. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-string.prototype.indexof
+description: String.prototype.indexOf type coercion for position parameter
+info: >
+  String.prototype.indexOf ( searchString [ , position ] )
+
+  4. Let pos be ? ToInteger(position).
+
+includes: [typeCoercion.js]
+---*/
+
+getValuesCoercibleToIntegerZero().forEach(function(zero) {
+  assert.sameValue("aaaa".indexOf("aa", zero), 0, "with value " + zero);
+});
+
+getValuesCoercibleToIntegerOne().forEach(function(one) {
+  assert.sameValue("aaaa".indexOf("aa", one), 1, "with value " + one);
+});
+
+getValuesCoercibleToIntegerFromInteger(2).forEach(function(two) {
+  assert.sameValue("aaaa".indexOf("aa", two), 2, "with value " + two);
+});
+
+getValuesNotCoercibleToInteger().forEach(function(pair) {
+  var error = pair.error;
+  var value = pair.value;
+  assert.throws(error, function() { "".indexOf("", value); });
+});