1 files changed, 107 insertions, 0 deletions
diff --git a/intl/components/src/DateIntervalFormat.h b/intl/components/src/DateIntervalFormat.h
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+++ b/intl/components/src/DateIntervalFormat.h
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+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+#ifndef intl_components_DateIntervalFormat_h_
+#define intl_components_DateIntervalFormat_h_
+
+#include "mozilla/intl/Calendar.h"
+#include "mozilla/intl/DateTimePart.h"
+#include "mozilla/intl/ICU4CGlue.h"
+#include "mozilla/intl/ICUError.h"
+#include "mozilla/Result.h"
+#include "mozilla/Span.h"
+#include "mozilla/UniquePtr.h"
+
+#include "unicode/udateintervalformat.h"
+#include "unicode/utypes.h"
+
+namespace mozilla::intl {
+class Calendar;
+
+using AutoFormattedDateInterval =
+    AutoFormattedResult<UFormattedDateInterval, udtitvfmt_openResult,
+                        udtitvfmt_resultAsValue, udtitvfmt_closeResult>;
+
+/**
+ * This component is a Mozilla-focused API for the date range formatting
+ * provided by ICU. This DateIntervalFormat class helps to format the range
+ * between two date-time values.
+ *
+ * https://tc39.es/ecma402/#sec-formatdatetimerange
+ * https://tc39.es/ecma402/#sec-formatdatetimerangetoparts
+ */
+class DateIntervalFormat final {
+ public:
+  /**
+   * Create a DateIntervalFormat object from locale, skeleton and time zone.
+   * The format of skeleton can be found in [1].
+   *
+   * Note: Skeleton will be removed in the future.
+   *
+   * [1]: https://unicode.org/reports/tr35/tr35-dates.html#Date_Format_Patterns
+   */
+  static Result<UniquePtr<DateIntervalFormat>, ICUError> TryCreate(
+      Span<const char> aLocale, Span<const char16_t> aSkeleton,
+      Span<const char16_t> aTimeZone);
+
+  ~DateIntervalFormat();
+
+  /**
+   * Format a date-time range between two Calendar objects.
+   *
+   * DateIntervalFormat cannot be changed to use a proleptic Gregorian
+   * calendar, so use this method if the start date is before the Gregorian
+   * calendar is introduced(October 15, 1582), otherwise use TryFormatDateTime
+   * instead.
+   *
+   * The result will be stored in aFormatted, caller can use
+   * AutoFormattedDateInterval::ToSpan() to get the formatted string, or pass
+   * the aFormatted to TryFormattedToParts to get the parts vector.
+   *
+   * aPracticallyEqual will be set to true if the date times of the two
+   * calendars are equal.
+   */
+  ICUResult TryFormatCalendar(const Calendar& aStart, const Calendar& aEnd,
+                              AutoFormattedDateInterval& aFormatted,
+                              bool* aPracticallyEqual) const;
+
+  /**
+   * Format a date-time range between two Unix epoch times in milliseconds.
+   *
+   * The result will be stored in aFormatted, caller can use
+   * AutoFormattedDateInterval::ToSpan() to get the formatted string, or pass
+   * the aFormatted to TryFormattedToParts to get the parts vector.
+   *
+   * aPracticallyEqual will be set to true if the date times of the two
+   * Unix epoch times are equal.
+   */
+  ICUResult TryFormatDateTime(double aStart, double aEnd,
+                              AutoFormattedDateInterval& aFormatted,
+                              bool* aPracticallyEqual) const;
+
+  /**
+   *  Convert the formatted DateIntervalFormat into several parts.
+   *
+   *  The caller get the formatted result from either TryFormatCalendar, or
+   *  TryFormatDateTime methods, and instantiate the DateTimePartVector. This
+   *  method will generate the parts and insert them into the vector.
+   *
+   *  See:
+   *  https://tc39.es/ecma402/#sec-formatdatetimerangetoparts
+   */
+  ICUResult TryFormattedToParts(const AutoFormattedDateInterval& aFormatted,
+                                DateTimePartVector& aParts) const;
+
+ private:
+  DateIntervalFormat() = delete;
+  explicit DateIntervalFormat(UDateIntervalFormat* aDif)
+      : mDateIntervalFormat(aDif) {}
+  DateIntervalFormat(const DateIntervalFormat&) = delete;
+  DateIntervalFormat& operator=(const DateIntervalFormat&) = delete;
+
+  ICUPointer<UDateIntervalFormat> mDateIntervalFormat =
+      ICUPointer<UDateIntervalFormat>(nullptr);
+};
+}  // namespace mozilla::intl
+
+#endif