🚧 ICU-23424 Initial implementation of Builder::setFormattingLocale()

icu4c/source/i18n/messageformat2.cpp

@@ -305,7 +305,7 @@ FunctionContext MessageFormatter::makeFunctionContext(const FunctionOptions& opt
     UMFBidiOption dir = ubidi_getMFOption(options.getStringFunctionOption(options::U_DIR));
     UnicodeString id = options.getStringFunctionOption(options::U_ID);
 
-    return FunctionContext(locale, dir, id);
+    return FunctionContext(locale, formattingLocale, dir, id);
 }
 
 // Resolves a function's options

icu4c/source/i18n/messageformat2_formatter.cpp

@@ -76,6 +76,11 @@ namespace message2 {
         return *this;
     }
 
+    MessageFormatter::Builder& MessageFormatter::Builder::setFormattingLocale(const Locale& loc) {
+      formattingLocale = loc;
+      return *this;
+    }
+
     MessageFormatter::Builder& MessageFormatter::Builder::setDataModel(MFDataModel&& newDataModel) {
         clearState();
         hasPattern = false;
@@ -119,7 +124,11 @@ namespace message2 {
         return MessageFormatter(*this, errorCode);
     }
 
-    MessageFormatter::Builder::Builder(UErrorCode& errorCode) : locale(Locale::getDefault()), customMFFunctionRegistry(nullptr) {
+    MessageFormatter::Builder::Builder(UErrorCode& errorCode) :
+      locale(Locale::getDefault()),
+      formattingLocale(),
+      customMFFunctionRegistry(nullptr) {
+      formattingLocale.setToBogus(); // indicating setFormattingLocale was not called
         // Initialize errors
         errors = new StaticErrors(errorCode);
         CHECK_ERROR(errorCode);
@@ -152,7 +161,10 @@ namespace message2 {
 
     // MessageFormatter
 
-    MessageFormatter::MessageFormatter(const MessageFormatter::Builder& builder, UErrorCode &success) : locale(builder.locale), customMFFunctionRegistry(builder.customMFFunctionRegistry) {
+    MessageFormatter::MessageFormatter(const MessageFormatter::Builder& builder, UErrorCode &success) :
+      locale(builder.locale),
+      formattingLocale(builder.formattingLocale.isBogus() ? builder.locale : builder.formattingLocale),
+      customMFFunctionRegistry(builder.customMFFunctionRegistry) {
         CHECK_ERROR(success);
 
         // Set up the standard function registry
@@ -236,6 +248,7 @@ namespace message2 {
         cleanup();
 
         locale = std::move(other.locale);
+        formattingLocale = std::move(other.formattingLocale);
         standardMFFunctionRegistry = std::move(other.standardMFFunctionRegistry);
         customMFFunctionRegistry = other.customMFFunctionRegistry;
         dataModel = std::move(other.dataModel);

icu4c/source/i18n/messageformat2_function_registry.cpp

@@ -734,15 +734,16 @@ StandardFunctions::NumberValue::NumberValue(const Number& parent,
         return;
     }
 
+    formattingLocale = context.getFormattingLocale();
     locale = context.getLocale();
     opts = options.mergeOptions(arg.getResolvedOptions(), errorCode);
     innerValue = arg.unwrap();
     functionName = UnicodeString(parent.isInteger ? "integer" : "number");
     inputDir = context.getDirection();
-    dir = outputDirectionalityFromUDir(inputDir, locale);
+    dir = outputDirectionalityFromUDir(inputDir, formattingLocale);
 
     number::LocalizedNumberFormatter realFormatter;
-    realFormatter = formatterForOptions(parent, locale, opts, errorCode);
+    realFormatter = formatterForOptions(parent, formattingLocale, opts, errorCode);
 
     int64_t integerValue = 0;
 
@@ -1063,6 +1064,7 @@ StandardFunctions::DateTimeValue::DateTimeValue(DateTime::DateTimeType type,
     }
 
     locale = context.getLocale();
+    formattingLocale = context.getFormattingLocale();
     opts = options.mergeOptions(arg.getResolvedOptions(), errorCode);
     innerValue = arg.unwrap();
     switch (type) {
@@ -1077,7 +1079,7 @@ StandardFunctions::DateTimeValue::DateTimeValue(DateTime::DateTimeType type,
         break;
     }
     inputDir = context.getDirection();
-    dir = outputDirectionalityFromUDir(inputDir, locale);
+    dir = outputDirectionalityFromUDir(inputDir, formattingLocale);
 
     const Formattable* source = &innerValue;
 
@@ -1119,19 +1121,19 @@ StandardFunctions::DateTimeValue::DateTimeValue(DateTime::DateTimeType type,
             timeStyle = stringToStyle(opts.getStringFunctionOption(timeStyleName), errorCode);
 
             if (useDate && !useTime) {
-                df.adoptInstead(DateFormat::createDateInstance(dateStyle, locale));
+                df.adoptInstead(DateFormat::createDateInstance(dateStyle, formattingLocale));
             } else if (useTime && !useDate) {
-                df.adoptInstead(DateFormat::createTimeInstance(timeStyle, locale));
+                df.adoptInstead(DateFormat::createTimeInstance(timeStyle, formattingLocale));
             } else {
-                df.adoptInstead(DateFormat::createDateTimeInstance(dateStyle, timeStyle, locale));
+                df.adoptInstead(DateFormat::createDateTimeInstance(dateStyle, timeStyle, formattingLocale));
             }
         } else if (type == DateTimeType::kDate) {
             dateStyle = stringToStyle(opts.getStringFunctionOption(styleName), errorCode);
-            df.adoptInstead(DateFormat::createDateInstance(dateStyle, locale));
+            df.adoptInstead(DateFormat::createDateInstance(dateStyle, formattingLocale));
         } else {
             // :time
             timeStyle = stringToStyle(opts.getStringFunctionOption(styleName), errorCode);
-            df.adoptInstead(DateFormat::createTimeInstance(timeStyle, locale));
+            df.adoptInstead(DateFormat::createTimeInstance(timeStyle, formattingLocale));
         }
     } else {
         // Build up a skeleton based on the field options, then use that to
@@ -1483,14 +1485,15 @@ StandardFunctions::StringValue::StringValue(const FunctionContext& context,
                                             const FunctionOptions&,
                                             UErrorCode& status) {
     CHECK_ERROR(status);
+    formattingLocale = context.getFormattingLocale();
     locale = context.getLocale();
     innerValue = val.unwrap();
     functionName = UnicodeString("string");
     inputDir = context.getDirection();
     dir = stringOutputDirection(inputDir);
     // No options
     // Convert to string
-    formattedString = formattableToString(context.getLocale(), innerValue, status);
+    formattedString = formattableToString(formattingLocale, innerValue, status);
 }
 
 void StandardFunctions::StringValue::selectKeys(const UnicodeString* keys,

icu4c/source/i18n/unicode/messageformat2.h

@@ -126,6 +126,18 @@ namespace message2 {
          */
         U_I18N_API const Locale& getLocale() const { return locale; }
 
+	/**
+	 * Acceses the formatting locale that this `MessageFormatter` object
+	 * was created with.  If no formatting locale was explicitly set,
+	 * returns the same locale as getLocale().
+	 *
+	 * @return A reference to the formatting locale.
+	 *
+	 * @internal ICU 79 technology preview
+	 * @deprecated This API is for technology preview only.
+	 */
+	U_I18N_API const Locale& getFormattingLocale() { return formattingLocale; }
+
         /**
          * Serializes the data model as a string in MessageFormat 2.0 syntax.
          *
@@ -230,6 +242,7 @@ namespace message2 {
             // Ignored if `setPattern()` wasn't called
             StaticErrors* errors;
             Locale locale;
+	    Locale formattingLocale;
             // Not owned
             const MFFunctionRegistry* customMFFunctionRegistry;
             // Error behavior; see comment in `MessageFormatter` class
@@ -244,7 +257,7 @@ namespace message2 {
             void clearState();
         public:
             /**
-             * Sets the locale to use for formatting.
+             * Sets the locale to use for this context
              *
              * @param locale The desired locale.
              * @return       A reference to the builder.
@@ -253,6 +266,18 @@ namespace message2 {
              * @deprecated This API is for technology preview only.
              */
             U_I18N_API Builder& setLocale(const Locale& locale);
+	    /**
+	     * Sets the locale used by formatter factories (:number, :date,
+	     * etc.) for rendering output. Selector factories (plural rules)
+	     * continue to use the locale set via setLocale().
+	     * The formatting locale defaults to the same one set by setLocale().
+	     * @param locale The desired locale
+	     * @return       A reference to the builder.
+	     *
+	     * @internal ICU 79 technology preview
+	     * @deprecated This API is for technology preview only.
+	     */
+	    U_I18N_API Builder& setFormattingLocale(const Locale& locale);
             /**
              * Sets the pattern (contents of the message) and parses it
              * into a data model. If a data model was
@@ -501,8 +526,10 @@ namespace message2 {
         void clearErrors() const;
         void cleanup() noexcept;
 
-        // The locale this MessageFormatter was created with
-        /* const */ Locale locale;
+        // The locale set by setLocale()
+	Locale locale;
+	// The locale set by setformattinglocale()
+	Locale formattingLocale;
 
         // Registry for built-in functions
         MFFunctionRegistry standardMFFunctionRegistry;

icu4c/source/i18n/unicode/messageformat2_function_registry.h

@@ -247,6 +247,15 @@ namespace message2 {
              * @deprecated This API is for technology preview only.
              */
             U_I18N_API const Locale& getLocale() const { return locale; }
+            /**
+             * Returns the formatting locale from this context.
+             *
+             * @return Formatting Locale the context was created with.
+             *
+             * @internal ICU 79 technology preview
+             * @deprecated This API is for technology preview only.
+             */
+            U_I18N_API const Locale& getFormattingLocale() const { return formattingLocale; }
             /**
              * Returns the text direction from this context.
              *
@@ -270,11 +279,12 @@ namespace message2 {
             friend class MessageFormatter;
 
             Locale locale;
+            Locale formattingLocale;
             UMFBidiOption dir;
             UnicodeString id;
 
-            FunctionContext(const Locale& loc, UMFBidiOption d, UnicodeString i)
-                : locale(loc), dir(d), id(i) {}
+            FunctionContext(const Locale& loc, const Locale& formatLoc, UMFBidiOption d, UnicodeString i)
+	      : locale(loc), formattingLocale(formatLoc), dir(d), id(i) {}
     }; // class FunctionContext
 
     class FunctionValue;
@@ -515,13 +525,21 @@ namespace message2 {
              */
             UnicodeString fallback;
             /**
-             * Locale from u:locale option.
+             * Locale from function context.
              * Must be set from function context.
              *
              * @internal ICU 79 technology preview
              * @deprecated This API is for technology preview only.
              */
             Locale locale;
+            /**
+             * Formatting Locale from function context.
+             * Must be set from function context.
+             *
+             * @internal ICU 79 technology preview
+             * @deprecated This API is for technology preview only.
+             */
+            Locale formattingLocale;
             /**
              * Directionality of formatted result.
              * Defaults to U_MF_DIRECTIONALITY_UNKNOWN if not set

icu4c/source/test/intltest/messageformat2test.cpp

@@ -31,6 +31,7 @@ TestMessageFormat2::runIndexedTest(int32_t index, UBool exec,
     TESTCASE_AUTO(testLowLoneSurrogate);
     TESTCASE_AUTO(testLoneSurrogateInQuotedLiteral);
     TESTCASE_AUTO(dataDrivenTests);
+    TESTCASE_AUTO(testSetFormatLocale);
     TESTCASE_AUTO_END;
 }
 
@@ -479,6 +480,43 @@ void TestMessageFormat2::dataDrivenTests() {
     jsonTestsFromFiles(errorCode);
 }
 
+void TestMessageFormat2::testSetFormatLocale() {
+    IcuTestErrorCode errorCode(*this, "testSetFormatLocale");
+    UParseError parseError;
+
+    UnicodeString pattern(u""
+                          ".input {$count :number} .input {$name :string} .input {$birthday :date}\n"
+                          ".match $count\n"
+                          "many {{PASS {$count} @ {$birthday :date style=short}}}\n"
+			  "* {{FAIL wrong bucket {$count} @ {$birthday :date style=short}}}\n"
+                          );
+    MessageFormatter mf = MessageFormatter::Builder(errorCode)
+      .setErrorHandlingBehavior(MessageFormatter::U_MF_BEST_EFFORT)
+      .setPattern(pattern, parseError, errorCode)
+      .setLocale(Locale("pl"))
+      .setFormattingLocale(Locale("en"))
+      .build(errorCode);
+
+    if (errorCode.errIfFailureAndReset("build")) {
+      errln("UParseError = %d:%d", parseError.line, parseError.offset);
+      return;
+    }
+
+    std::map<UnicodeString, message2::Formattable> argsBuilder;
+    argsBuilder["count"] = message2::Formattable((int64_t)13);
+    argsBuilder["name"] = message2::Formattable("US");
+    argsBuilder["birthday"] = message2::Formattable("1776-07-04");
+    MessageArguments args(argsBuilder, errorCode);
+
+    UnicodeString result = mf.formatToString(args, errorCode);
+    if (errorCode.errIfFailureAndReset("formatToString")) {
+        return;
+    }
+    UnicodeString expectedResult(u"PASS 13 @ 7/4/76");
+    assertEquals("testSetFormatLocale", expectedResult, result);
+}
+
+
 TestCase::~TestCase() {}
 TestCase::Builder::~Builder() {}
 

icu4c/source/test/intltest/messageformat2test.h

@@ -53,6 +53,7 @@ class TestMessageFormat2: public IntlTest {
     void testBidiAPI(void);
     void testAPI(void);
     void testAPISimple(void);
+    void testSetFormatLocale(void);
 
 private:
     void jsonTestsFromFiles(IcuTestErrorCode&);