1 files changed, 32 insertions, 0 deletions
diff --git a/js/src/tests/test262/built-ins/Temporal/PlainDateTime/prototype/toString/fractionalseconddigits-non-integer.js b/js/src/tests/test262/built-ins/Temporal/PlainDateTime/prototype/toString/fractionalseconddigits-non-integer.js
new file mode 100644
index 0000000000..38444c4b52
--- /dev/null
+++ b/js/src/tests/test262/built-ins/Temporal/PlainDateTime/prototype/toString/fractionalseconddigits-non-integer.js
@@ -0,0 +1,32 @@
+// |reftest| skip-if(!this.hasOwnProperty('Temporal')) -- Temporal is not enabled unconditionally
+// Copyright (C) 2021 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-temporal.plaindatetime.prototype.tostring
+description: Rounding for fractionalSecondDigits option
+info: |
+    sec-getstringornumberoption step 3.b:
+      b. Return floor(ℝ(_value_)).
+    sec-temporal-tosecondsstringprecision step 9:
+      9. Let _digits_ be ? GetStringOrNumberOption(_normalizedOptions_, *"fractionalSecondDigits"*, « *"auto"* », 0, 9, *"auto"*).
+    sec-temporal.plaindatetime.prototype.tostring step 4:
+      4. Let _precision_ be ? ToSecondsStringPrecision(_options_).
+features: [Temporal]
+---*/
+
+const datetime = new Temporal.PlainDateTime(2000, 5, 2, 12, 34, 56, 987, 650, 0);
+
+let string = datetime.toString({ fractionalSecondDigits: 2.5 });
+assert.sameValue(string, "2000-05-02T12:34:56.98", "fractionalSecondDigits 2.5 floors to 2");
+
+string = datetime.toString({ fractionalSecondDigits: 9.7 });
+assert.sameValue(string, "2000-05-02T12:34:56.987650000", "fractionalSecondDigits 9.7 floors to 9 and is not out of range");
+
+assert.throws(
+  RangeError,
+  () => datetime.toString({ fractionalSecondDigits: -0.6 }),
+  "fractionalSecondDigits -0.6 floors to -1 and is out of range"
+);
+
+reportCompare(0, 0);