1 files changed, 126 insertions, 0 deletions
diff --git a/intl/icu/source/i18n/number_usageprefs.h b/intl/icu/source/i18n/number_usageprefs.h
new file mode 100644
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+++ b/intl/icu/source/i18n/number_usageprefs.h
@@ -0,0 +1,126 @@
+// © 2020 and later: Unicode, Inc. and others.
+// License & terms of use: http://www.unicode.org/copyright.html
+
+#include "unicode/utypes.h"
+
+#if !UCONFIG_NO_FORMATTING
+#ifndef __NUMBER_USAGEPREFS_H__
+#define __NUMBER_USAGEPREFS_H__
+
+#include "cmemory.h"
+#include "number_types.h"
+#include "unicode/listformatter.h"
+#include "unicode/localpointer.h"
+#include "unicode/locid.h"
+#include "unicode/measunit.h"
+#include "unicode/stringpiece.h"
+#include "unicode/uobject.h"
+#include "units_converter.h"
+#include "units_router.h"
+
+U_NAMESPACE_BEGIN
+
+using ::icu::units::ComplexUnitsConverter;
+using ::icu::units::UnitsRouter;
+
+namespace number {
+namespace impl {
+
+/**
+ * A MicroPropsGenerator which uses UnitsRouter to produce output converted to a
+ * MeasureUnit appropriate for a particular localized usage: see
+ * NumberFormatterSettings::usage().
+ */
+class U_I18N_API UsagePrefsHandler : public MicroPropsGenerator, public UMemory {
+  public:
+    UsagePrefsHandler(const Locale &locale, const MeasureUnit &inputUnit, const StringPiece usage,
+                      const MicroPropsGenerator *parent, UErrorCode &status);
+
+    /**
+     * Obtains the appropriate output value, MeasureUnit and
+     * rounding/precision behaviour from the UnitsRouter.
+     *
+     * The output unit is passed on to the LongNameHandler via
+     * micros.outputUnit.
+     */
+    void processQuantity(DecimalQuantity &quantity, MicroProps &micros,
+                         UErrorCode &status) const override;
+
+    /**
+     * Returns the list of possible output units, i.e. the full set of
+     * preferences, for the localized, usage-specific unit preferences.
+     *
+     * The returned pointer should be valid for the lifetime of the
+     * UsagePrefsHandler instance.
+     */
+    const MaybeStackVector<MeasureUnit> *getOutputUnits() const {
+        return fUnitsRouter.getOutputUnits();
+    }
+
+  private:
+    UnitsRouter fUnitsRouter;
+    const MicroPropsGenerator *fParent;
+};
+
+} // namespace impl
+} // namespace number
+
+// Export explicit template instantiations of LocalPointerBase and LocalPointer.
+// This is required when building DLLs for Windows. (See datefmt.h,
+// collationiterator.h, erarules.h and others for similar examples.)
+//
+// Note: These need to be outside of the number::impl namespace, or Clang will
+// generate a compile error.
+#if U_PF_WINDOWS <= U_PLATFORM && U_PLATFORM <= U_PF_CYGWIN
+#if defined(_MSC_VER)
+// Ignore warning 4661 as LocalPointerBase does not use operator== or operator!=
+#pragma warning(push)
+#pragma warning(disable: 4661)
+#endif
+template class U_I18N_API LocalPointerBase<ComplexUnitsConverter>;
+template class U_I18N_API LocalPointer<ComplexUnitsConverter>;
+#if defined(_MSC_VER)
+#pragma warning(pop)
+#endif
+#endif
+
+namespace number {
+namespace impl {
+
+/**
+ * A MicroPropsGenerator which converts a measurement from one MeasureUnit to
+ * another. In particular, the output MeasureUnit may be a mixed unit. (The
+ * input unit may not be a mixed unit.)
+ */
+class U_I18N_API UnitConversionHandler : public MicroPropsGenerator, public UMemory {
+  public:
+    /**
+     * Constructor.
+     *
+     * @param targetUnit Specifies the output MeasureUnit. The input MeasureUnit
+     *     is derived from it: in case of a mixed unit, the biggest unit is
+     *     taken as the input unit. If not a mixed unit, the input unit will be
+     *     the same as the output unit and no unit conversion takes place.
+     * @param parent The parent MicroPropsGenerator.
+     * @param status Receives status.
+     */
+    UnitConversionHandler(const MeasureUnit &targetUnit, const MicroPropsGenerator *parent,
+                          UErrorCode &status);
+
+    /**
+     * Obtains the appropriate output values from the Unit Converter.
+     */
+    void processQuantity(DecimalQuantity &quantity, MicroProps &micros,
+                         UErrorCode &status) const override;
+  private:
+    MeasureUnit fOutputUnit;
+    LocalPointer<ComplexUnitsConverter> fUnitConverter;
+    const MicroPropsGenerator *fParent;
+};
+
+} // namespace impl
+} // namespace number
+U_NAMESPACE_END
+
+#endif // __NUMBER_USAGEPREFS_H__
+#endif /* #if !UCONFIG_NO_FORMATTING */