1 files changed, 215 insertions, 0 deletions
diff --git a/src/mbgl/style/expression/number_format.cpp b/src/mbgl/style/expression/number_format.cpp
new file mode 100644
index 0000000000..e31a9ce398
--- /dev/null
+++ b/src/mbgl/style/expression/number_format.cpp
@@ -0,0 +1,215 @@
+#include <mbgl/style/expression/number_format.hpp>
+#include <mbgl/style/conversion_impl.hpp>
+#include <mbgl/util/platform.hpp>
+
+namespace mbgl {
+namespace style {
+namespace expression {
+
+const char localeKey[] = "locale";
+const char currencyKey[] = "currency";
+const char minFractionDigitsKey[] = "min-fraction-digits";
+const char maxFractionDigitsKey[] = "max-fraction-digits";
+
+NumberFormat::NumberFormat(std::unique_ptr<Expression> number_,
+                           std::unique_ptr<Expression> locale_,
+                           std::unique_ptr<Expression> currency_,
+                           std::unique_ptr<Expression> minFractionDigits_,
+                           std::unique_ptr<Expression> maxFractionDigits_)
+    : Expression(Kind::NumberFormat, type::String),
+      number(std::move(number_)),
+      locale(std::move(locale_)),
+      currency(std::move(currency_)),
+      minFractionDigits(std::move(minFractionDigits_)),
+      maxFractionDigits(std::move(maxFractionDigits_))
+{}
+
+NumberFormat::~NumberFormat() = default;
+
+EvaluationResult NumberFormat::evaluate(const EvaluationContext& params) const {
+    auto numberResult = number->evaluate(params);
+    if (!numberResult) {
+        return numberResult.error();
+    }
+    double evaluatedNumber = numberResult->get<double>();
+    
+    std::string evaluatedLocale;
+    if (locale) {
+        auto localeResult = locale->evaluate(params);
+        if (!localeResult) {
+            return localeResult.error();
+        }
+        evaluatedLocale = toString(*localeResult);
+    }
+
+    std::string evaluatedCurrency;
+    if (currency) {
+        auto currencyResult = currency->evaluate(params);
+        if (!currencyResult) {
+            return currencyResult.error();
+        }
+        evaluatedCurrency = toString(*currencyResult);
+    }
+
+    uint8_t evaluatedMinFractionDigits = 0;
+    if (minFractionDigits) {
+        auto minDigitsResult = minFractionDigits->evaluate(params);
+        if (!minDigitsResult) {
+            return minDigitsResult.error();
+        }
+        evaluatedMinFractionDigits = minDigitsResult->get<double>();
+    }
+
+    uint8_t evaluatedMaxFractionDigits = 3;
+    if (maxFractionDigits) {
+        auto maxDigitsResult = maxFractionDigits->evaluate(params);
+        if (!maxDigitsResult) {
+            return maxDigitsResult.error();
+        }
+        evaluatedMaxFractionDigits = maxDigitsResult->get<double>();
+    }
+
+    std::string output;
+    output = platform::formatNumber(evaluatedNumber,
+                                    evaluatedLocale,
+                                    evaluatedCurrency,
+                                    evaluatedMinFractionDigits,
+                                    evaluatedMaxFractionDigits);
+    return output;
+}
+
+void NumberFormat::eachChild(const std::function<void(const Expression&)>& visit) const {
+    visit(*number);
+    if (locale) visit(*locale);
+    if (currency) visit(*currency);
+    if (minFractionDigits) visit(*minFractionDigits);
+    if (maxFractionDigits) visit(*maxFractionDigits);
+}
+
+bool NumberFormat::operator==(const Expression& e) const {
+    if (e.getKind() == Kind::NumberFormat) {
+        auto rhs = static_cast<const NumberFormat*>(&e);
+        if ((locale && (!rhs->locale || *locale != *rhs->locale)) ||
+            (!locale && rhs->locale)) {
+            return false;
+        }
+        if ((currency && (!rhs->currency || *currency != *rhs->currency)) ||
+            (!currency && rhs->currency)) {
+            return false;
+        }
+        if ((minFractionDigits && (!rhs->minFractionDigits || *minFractionDigits != *rhs->minFractionDigits)) ||
+            (!minFractionDigits && rhs->minFractionDigits)) {
+            return false;
+        }
+        if ((maxFractionDigits && (!rhs->maxFractionDigits || *maxFractionDigits != *rhs->maxFractionDigits)) ||
+            (!maxFractionDigits && rhs->maxFractionDigits)) {
+            return false;
+        }
+        return *number == *rhs->number;
+    }
+    return false;
+}
+
+std::vector<optional<Value>> NumberFormat::possibleOutputs() const {
+    return { nullopt };
+}
+
+using namespace mbgl::style::conversion;
+ParseResult NumberFormat::parse(const Convertible& value, ParsingContext& ctx) {
+    std::size_t length = arrayLength(value);
+
+    if (length != 3) {
+        ctx.error("Expected two arguments, but found " + util::toString(length) + " instead.");
+        return ParseResult();
+    }
+
+    ParseResult numberResult = ctx.parse(arrayMember(value, 1), 1, {type::Number});
+    if (!numberResult) {
+        ctx.error("Failed to parse the number.");
+        return ParseResult();
+    }
+
+    type::Type type = (*numberResult)->getType();
+    if (!type.is<type::NumberType>()) {
+        ctx.error("Expected argument of type number, but found " + toString(type) + " instead.");
+        return ParseResult();
+    }
+
+    auto options = arrayMember(value, 2);
+    if (!isObject(options)) {
+        ctx.error("Number-format options argument must be an object.");
+        return ParseResult();
+    }
+
+    const optional<Convertible> localeOption = objectMember(options, localeKey);
+    ParseResult localeResult;
+    if (localeOption) {
+        localeResult = ctx.parse(*localeOption, 1, {type::String});
+        if (!localeResult) {
+            ctx.error("Number-format locale parsing failed.");
+            return ParseResult();
+        }
+    }
+
+    const optional<Convertible> currencyOption = objectMember(options, currencyKey);
+    ParseResult currencyResult;
+    if (currencyOption) {
+        currencyResult = ctx.parse(*currencyOption, 1, {type::String});
+        if (!currencyResult) {
+            ctx.error("Number-format currency parsing failed.");
+            return ParseResult();
+        }
+    }
+
+    const optional<Convertible> minFractionDigitsOption = objectMember(options, minFractionDigitsKey);
+    ParseResult minFractionDigitsResult;
+    if (minFractionDigitsOption) {
+        minFractionDigitsResult = ctx.parse(*minFractionDigitsOption, 1, {type::Number});
+        if (!minFractionDigitsResult) {
+            ctx.error("Number-format min-fraction-digits parsing failed.");
+            return ParseResult();
+        }
+    }
+
+    const optional<Convertible> maxFractionDigitsOption = objectMember(options, maxFractionDigitsKey);
+    ParseResult maxFractionDigitsResult;
+    if (maxFractionDigitsOption) {
+        maxFractionDigitsResult = ctx.parse(*maxFractionDigitsOption, 1, {type::Number});
+        if (!maxFractionDigitsResult) {
+            ctx.error("Number-format max-fraction-digits parsing failed.");
+            return ParseResult();
+        }
+    }
+
+    return ParseResult(std::make_unique<NumberFormat>(std::move(*numberResult),
+                                                      localeResult ? std::move(*localeResult) : nullptr,
+                                                      currencyResult? std::move(*currencyResult) : nullptr,
+                                                      minFractionDigitsResult ? std::move(*minFractionDigitsResult) : nullptr,
+                                                      maxFractionDigitsResult ? std::move(*maxFractionDigitsResult) : nullptr));
+}
+
+mbgl::Value NumberFormat::serialize() const {
+    std::vector<mbgl::Value> serialized{{ getOperator() }};
+    serialized.emplace_back(number->serialize());
+
+    std::unordered_map<std::string, mbgl::Value> options;
+    if (locale) {
+        options[localeKey] = locale->serialize();
+    }
+    if (currency) {
+        options[currencyKey] = currency->serialize();
+    }
+    if (minFractionDigits) {
+        options[minFractionDigitsKey] = minFractionDigits->serialize();
+    }
+    if (maxFractionDigits) {
+        options[maxFractionDigitsKey] = maxFractionDigits->serialize();
+    }
+    serialized.emplace_back(options);
+
+    return serialized;
+}
+
+} // namespace expression
+} // namespace style
+} // namespace mbgl