feat: add currency formatter

Cargo.toml

@@ -38,6 +38,8 @@ icu_calendar = { version = "1.5", default-features = false }
 icu_list = { version = "1.5", default-features = false }
 icu_decimal = { version = "1.5", default-features = false }
 icu_locid_transform = { version = "1.5", default-features = false }
+icu_experimental = { version = "0.1.0", default_features = false }
+tinystr = "0.7.6"
 
 # internal use
 tests_common = { path = "./tests/common", version = "0.1.0" }

docs/book/src/06_features.md

@@ -89,3 +89,7 @@ Allow the use of the `list` formatter.
 #### `format_nums`
 
 Allow the use of the `number` formatter.
+
+#### `format_currency`
+
+Allow the use of the `currency` formatter.

docs/book/src/declare/08_formatters.md

@@ -84,6 +84,42 @@ let num = move || 100_000;
 t!(i18n, number_formatter, num);
 ```
 
+## Currency (experimental)
+
+```json
+{
+  "currency_formatter": "{{ num, currency }}"
+}
+```
+
+Will format the currency based on the locale.
+The variable should be the same as [number](#number).
+
+Enable the "format_currency" feature to use the number formatter.
+
+### Arguments
+
+There are two arguments at the moment for the currency formatter: `width` and `country_code`, which are based on [`icu_experimental::dimension::currency::options::Width`](https://docs.rs/icu_experimental/0.1.0/icu_experimental/dimension/currency/options/enum.Width.html) and [`icu_experimental::dimension::currency::formatter::CountryCode`](https://docs.rs/icu_experimental/0.1.0/icu_experimental/dimension/currency/formatter/struct.CurrencyCode.html).
+
+`width` values:
+
+- short (default)
+- narrow
+
+`country_code` value should be a [currency code](https://www.iban.com/currency-codes), such as USD or EUR. The USD is the default value.
+
+### Example
+
+```rust,ignore
+use crate::i18n::*;
+
+let i18n = use_i18n();
+
+let num = move || 100_000;
+
+t!(i18n, currency_formatter, num);
+```
+
 ## Date
 
 ```json

leptos_i18n/Cargo.toml

@@ -28,6 +28,7 @@ icu_list = { workspace = true, optional = true }
 icu_decimal = { workspace = true, optional = true }
 typed-builder = "0.20"
 fixed_decimal = { workspace = true, optional = true, features = ["ryu"] }
+icu_experimental = { workspace = true, optional = true, features = ["ryu"] }
 writeable = "0.5"
 serde = "1.0"
 async-once-cell = { version = "0.5.3", optional = true }
@@ -36,6 +37,7 @@ serde-wasm-bindgen = { version = "0.6.5", optional = true }
 futures = { version = "0.3.30", optional = true }
 default-struct-builder = "0.5"
 wasm-bindgen = "0.2.96"
+tinystr = { workspace = true }
 
 [features]
 default = ["cookie", "json_files", "icu_compiled_data"]
@@ -46,6 +48,7 @@ icu_compiled_data = [
   "icu_calendar?/compiled_data",
   "icu_list?/compiled_data",
   "icu_decimal?/compiled_data",
+  "icu_experimental?/compiled_data",
   "leptos_i18n_macro/icu_compiled_data",
 ]
 plurals = ["dep:icu_plurals", "dep:icu_provider", "leptos_i18n_macro/plurals"]
@@ -66,6 +69,12 @@ format_nums = [
   "dep:icu_provider",
   "leptos_i18n_macro/format_nums",
 ]
+format_currency = [
+  "format_nums",
+  "dep:icu_experimental",
+  "dep:icu_provider",
+  "leptos_i18n_macro/format_currency",
+]
 actix = ["ssr", "leptos-use/actix"]
 axum = ["ssr", "leptos-use/axum"]
 hydrate = [
@@ -102,7 +111,13 @@ track_locale_files = ["leptos_i18n_macro/track_locale_files"]
 
 [package.metadata."docs.rs"]
 # Features needed for the doctests
-features = ["plurals", "format_datetime", "format_list", "format_nums"]
+features = [
+  "plurals",
+  "format_datetime",
+  "format_list",
+  "format_nums",
+  "format_currency",
+]
 
 
 [package.metadata.cargo-all-features]
@@ -163,4 +178,5 @@ always_include_features = [
   "format_datetime",
   "format_list",
   "format_nums",
+  "format_currency",
 ]

leptos_i18n/src/lib.rs

@@ -171,15 +171,18 @@ pub mod __private {
 
 /// This module contain utilities to create custom ICU providers.
 pub mod custom_provider {
-    pub use crate::macro_helpers::formatting::data_provider::IcuDataProvider;
-    pub use crate::macro_helpers::formatting::inner::set_icu_data_provider;
+    pub use crate::macro_helpers::formatting::{
+        data_provider::IcuDataProvider, inner::set_icu_data_provider,
+    };
     pub use leptos_i18n_macro::IcuDataProvider;
 }
 
 /// Reexports of backend libraries, mostly about formatting.
 pub mod reexports {
     #[cfg(feature = "format_nums")]
     pub use fixed_decimal;
+    #[cfg(feature = "format_currency")]
+    pub use tinystr::tinystr;
 
     /// module containing reexports of crates from the icu project
     pub mod icu {
@@ -189,6 +192,8 @@ pub mod reexports {
         pub use icu_datetime as datetime;
         #[cfg(feature = "format_nums")]
         pub use icu_decimal as decimal;
+        #[cfg(feature = "format_currency")]
+        pub use icu_experimental::dimension::currency;
         #[cfg(feature = "format_list")]
         pub use icu_list as list;
         #[cfg(feature = "plurals")]

leptos_i18n/src/macro_helpers/formatting/currency.rs

@@ -0,0 +1,91 @@
+use super::{IntoFixedDecimal, NumberFormatterInputFn};
+use crate::Locale;
+use core::fmt::{self, Display};
+use icu_experimental::dimension::currency::{
+    formatter::CurrencyCode, options::Width as CurrencyWidth,
+};
+use leptos::IntoView;
+
+use serde::{Deserialize, Serialize};
+use writeable::Writeable;
+
+// TODO: this struct should be removed in version ICU4x v2
+// Reference: https://docs.rs/icu_experimental/0.1.0/icu_experimental/dimension/currency/options/enum.Width.html
+// Issue: https://github.com/unicode-org/icu4x/pull/6100
+#[derive(Debug, Eq, PartialEq, Clone, Copy, Hash, Serialize, Deserialize)]
+#[non_exhaustive]
+#[doc(hidden)]
+pub enum Width {
+    #[serde(rename = "short")]
+    Short,
+
+    #[serde(rename = "narrow")]
+    Narrow,
+}
+
+impl Default for Width {
+    fn default() -> Self {
+        Self::Short
+    }
+}
+
+impl From<CurrencyWidth> for Width {
+    fn from(value: CurrencyWidth) -> Self {
+        match value {
+            CurrencyWidth::Short => Self::Short,
+            CurrencyWidth::Narrow => Self::Narrow,
+            _ => unimplemented!(),
+        }
+    }
+}
+
+#[doc(hidden)]
+pub fn format_currency_to_view<L: Locale>(
+    locale: L,
+    number: impl NumberFormatterInputFn,
+    width: CurrencyWidth,
+    currency_code: CurrencyCode,
+) -> impl IntoView + Clone {
+    let currency_formatter = super::get_currency_formatter(locale, width);
+
+    move || {
+        let fixed_dec = number.to_fixed_decimal();
+        let currency = currency_formatter.format_fixed_decimal(&fixed_dec, currency_code);
+        let mut formatted_currency = String::new();
+        currency.write_to(&mut formatted_currency).unwrap();
+        formatted_currency
+    }
+}
+
+#[doc(hidden)]
+pub fn format_currency_to_formatter<L: Locale>(
+    f: &mut fmt::Formatter<'_>,
+    locale: L,
+    number: impl IntoFixedDecimal,
+    width: CurrencyWidth,
+    currency_code: CurrencyCode,
+) -> fmt::Result {
+    let currency_formatter = super::get_currency_formatter(locale, width);
+    let fixed_dec = number.to_fixed_decimal();
+    let formatted_currency = currency_formatter.format_fixed_decimal(&fixed_dec, currency_code);
+    formatted_currency.write_to(f)
+}
+
+/// This function is a lie.
+/// The only reason it exist is for the `format` macros.
+/// It does NOT return a `impl Display` struct with no allocation like the other
+/// This directly return a `String` of the formatted num, because borrow issues.
+#[doc(hidden)]
+pub fn format_currency_to_display<L: Locale>(
+    locale: L,
+    number: impl IntoFixedDecimal,
+    width: CurrencyWidth,
+    currency_code: CurrencyCode,
+) -> impl Display {
+    let currency_formatter = super::get_currency_formatter(locale, width);
+    let fixed_dec = number.to_fixed_decimal();
+    let currency = currency_formatter.format_fixed_decimal(&fixed_dec, currency_code);
+    let mut formatted_currency = String::new();
+    currency.write_to(&mut formatted_currency).unwrap();
+    formatted_currency
+}