add unic-langid FromValue implementation

Cargo.toml

@@ -71,6 +71,7 @@ serde_json = "1"
 mysql-common-derive = { path = "derive", version = "0.30.2", optional = true }
 btoi = "0.4.3"
 zstd = "0.13"
+unic-langid = { version = "0.9.4", optional = true }
 
 [dev-dependencies]
 proptest = "1.0"
@@ -104,6 +105,7 @@ test = ["derive"]
 derive = ["mysql-common-derive"]
 binlog = ["bitvec"]
 nightly = ["test"]
+unic-langid = ["dep:unic-langid"]
 
 [package.metadata.docs.rs]
 rustdoc-args = ["--cfg", "docsrs"]
@@ -119,4 +121,5 @@ features = [
     "bigdecimal",
     "derive",
     "binlog",
+    "unic-langid",
 ]

src/value/convert/mod.rs

@@ -31,6 +31,7 @@ pub mod decimal;
 pub mod time;
 pub mod time02;
 pub mod uuid;
+pub mod unic_langid;
 
 lazy_static::lazy_static! {
     static ref DATETIME_RE_YMD: Regex = Regex::new(r"^\d{4}-\d{2}-\d{2}$").unwrap();

src/value/convert/unic_langid.rs

@@ -0,0 +1,60 @@
+//! This module implements conversion to ISO language-locale identifiers
+//! See [unic-locale](https://github.com/zbraniecki/unic-locale)
+
+#![cfg(feature = "unic-langid")]
+
+use std::convert::TryFrom;
+use unic_langid::LanguageIdentifier;
+
+use super::{FromValue, FromValueError, ParseIr, Value};
+
+#[cfg_attr(docsrs, doc(cfg(feature = "unic-langid")))]
+impl TryFrom<Value> for ParseIr<LanguageIdentifier> {
+    type Error = FromValueError;
+
+    fn try_from(value: Value) -> Result<Self, Self::Error> {
+        match &value {
+            Value::Bytes(b) => match LanguageIdentifier::from_bytes(b) {
+                Ok(ident) => Ok(ParseIr(ident, value)),
+                Err(_) => Err(FromValueError(value)),
+            },
+            _ => Err(FromValueError(value)),
+        }
+    }
+}
+
+#[cfg_attr(docsrs, doc(cfg(feature = "unic-langid")))]
+impl From<ParseIr<LanguageIdentifier>> for LanguageIdentifier {
+    fn from(value: ParseIr<LanguageIdentifier>) -> Self {
+        value.commit()
+    }
+}
+
+#[cfg_attr(docsrs, doc(cfg(feature = "unic-langid")))]
+impl From<ParseIr<LanguageIdentifier>> for Value {
+    fn from(value: ParseIr<LanguageIdentifier>) -> Self {
+        value.rollback()
+    }
+}
+
+#[cfg_attr(docsrs, doc(cfg(feature = "unic-langid")))]
+impl FromValue for LanguageIdentifier {
+    type Intermediate = ParseIr<LanguageIdentifier>;
+}
+
+#[cfg_attr(docsrs, doc(cfg(feature = "unic-langid")))]
+impl From<LanguageIdentifier> for Value {
+    fn from(lang_ident: LanguageIdentifier) -> Value {
+        Value::Bytes(lang_ident.to_string().into())
+    }
+}
+
+#[test]
+fn can_convert_sql_locale_to_ident() {
+    let value = Value::Bytes(String::from("en-US").into_bytes());
+
+    let ident = LanguageIdentifier::from_value(value);
+
+    assert_eq!(ident.language.to_string().as_str(), "en");
+    assert_eq!(ident.to_string().as_str(), "en-US");
+}