feat: Text adapter (#2894)

sqlx-sqlite/src/types/mod.rs

@@ -124,12 +124,14 @@
 //! over a floating-point type in the first place.
 //!
 //! Instead, you should only use a type affinity that SQLite will not attempt to convert implicitly,
-//! such as `TEXT` or `BLOB`, and map values to/from SQLite as strings.
+//! such as `TEXT` or `BLOB`, and map values to/from SQLite as strings. You can do this easily
+//! using [the `Text` adapter].
+//!
 //!
 //! [`decimal.c`]: https://www.sqlite.org/floatingpoint.html#the_decimal_c_extension
 //! [amalgamation]: https://www.sqlite.org/amalgamation.html
 //! [type-affinity]: https://www.sqlite.org/datatype3.html#type_affinity
-//!
+//! [the `Text` adapter]: Text
 
 pub(crate) use sqlx_core::types::*;
 
@@ -142,6 +144,7 @@ mod int;
 #[cfg(feature = "json")]
 mod json;
 mod str;
+mod text;
 #[cfg(feature = "time")]
 mod time;
 mod uint;

sqlx-sqlite/src/types/text.rs

@@ -0,0 +1,37 @@
+use crate::{Sqlite, SqliteArgumentValue, SqliteTypeInfo, SqliteValueRef};
+use sqlx_core::decode::Decode;
+use sqlx_core::encode::{Encode, IsNull};
+use sqlx_core::error::BoxDynError;
+use sqlx_core::types::{Text, Type};
+use std::fmt::Display;
+use std::str::FromStr;
+
+impl<T> Type<Sqlite> for Text<T> {
+    fn type_info() -> SqliteTypeInfo {
+        <String as Type<Sqlite>>::type_info()
+    }
+
+    fn compatible(ty: &SqliteTypeInfo) -> bool {
+        <String as Type<Sqlite>>::compatible(ty)
+    }
+}
+
+impl<'q, T> Encode<'q, Sqlite> for Text<T>
+where
+    T: Display,
+{
+    fn encode_by_ref(&self, buf: &mut Vec<SqliteArgumentValue<'q>>) -> IsNull {
+        Encode::<Sqlite>::encode(self.0.to_string(), buf)
+    }
+}
+
+impl<'r, T> Decode<'r, Sqlite> for Text<T>
+where
+    T: FromStr,
+    BoxDynError: From<<T as FromStr>::Err>,
+{
+    fn decode(value: SqliteValueRef<'r>) -> Result<Self, BoxDynError> {
+        let s: &str = Decode::<Sqlite>::decode(value)?;
+        Ok(Self(s.parse()?))
+    }
+}