Intl.DateTimeFormat hourCycle tests (#1265)

test/intl402/DateTimeFormat/prototype/resolvedOptions/hourCycle.js

+// Copyright 2017 Mozilla Corporation. All rights reserved.
+// This code is governed by the license found in the LICENSE file.
+
+/*---
+esid: sec-Intl.DateTimeFormat.prototype.resolvedOptions
+description: >
+  Intl.DateTimeFormat.prototype.resolvedOptions properly
+  reflect hourCycle settings.
+info: >
+  12.4.5 Intl.DateTimeFormat.prototype.resolvedOptions()
+
+includes: [testIntl.js]
+---*/
+
+/* Values passed via unicode extension key work */
+
+/**
+ * Since at the moment of writing, CLDR does not provide data for any locale
+ * that would allow it to use both 0-based and 1-based hourCycles,
+ * we can only test if the result is within the pair of h11/h12 or h23/h24.
+ */
+const hcValuePairs = [
+  ["h11", "h12"],
+  ["h23", "h24"]
+];
+
+const hour12Values = ['h11', 'h12'];
+const hour24Values = ['h23', 'h24'];
+
+for (const hcValuePair of hcValuePairs) {
+  for (const hcValue of hcValuePair) {
+    const resolvedOptions = new Intl.DateTimeFormat(`de-u-hc-${hcValue}`, {
+      hour: 'numeric'
+    }).resolvedOptions();
+
+    mustHaveProperty(resolvedOptions, 'hourCycle', hcValuePair);
+    mustHaveProperty(resolvedOptions, 'hour12', [hour12Values.includes(hcValue)]);
+  }
+}
+
+/* Values passed via options work */
+
+for (const hcValuePair of hcValuePairs) {
+  for (const hcValue of hcValuePair) {
+    const resolvedOptions = new Intl.DateTimeFormat(`en-US`, {
+      hour: 'numeric',
+      hourCycle: hcValue
+    }).resolvedOptions();
+
+    mustHaveProperty(resolvedOptions, 'hourCycle', hcValuePair);
+    mustHaveProperty(resolvedOptions, 'hour12', [hour12Values.includes(hcValue)]);
+  }
+}
+
+/* When both extension key and option is passed, option takes precedence */
+
+let resolvedOptions = new Intl.DateTimeFormat(`en-US-u-hc-h12`, {
+  hour: 'numeric',
+  hourCycle: 'h23'
+}).resolvedOptions();
+
+mustHaveProperty(resolvedOptions, 'hourCycle', ['h23', 'h24']);
+mustHaveProperty(resolvedOptions, 'hour12', [false]);
+
+/* When hour12 and hourCycle are set, hour12 takes precedence */
+
+resolvedOptions = new Intl.DateTimeFormat(`fr`, {
+  hour: 'numeric',
+  hour12: true,
+  hourCycle: 'h23'
+}).resolvedOptions();
+
+mustHaveProperty(resolvedOptions, 'hourCycle', ['h11', 'h12']);
+mustHaveProperty(resolvedOptions, 'hour12', [true]);
+
+/* When hour12 and extension key are set, hour12 takes precedence */
+
+resolvedOptions = new Intl.DateTimeFormat(`fr-u-hc-h24`, {
+  hour: 'numeric',
+  hour12: true,
+}).resolvedOptions();
+
+mustHaveProperty(resolvedOptions, 'hourCycle', ['h11', 'h12']);
+mustHaveProperty(resolvedOptions, 'hour12', [true]);