1 files changed, 30 insertions, 0 deletions
diff --git a/src/db/mod.rs b/src/db/mod.rs
index fa3d74e..6005813 100644
--- a/src/db/mod.rs
+++ b/src/db/mod.rs
@@ -4,6 +4,7 @@ use std::str::FromStr;
 
 use hex_literal::hex;
 use sqlx::{
+    error::{DatabaseError, ErrorKind},
     migrate::{Migrate as _, MigrateDatabase as _},
     sqlite::{Sqlite, SqliteConnectOptions, SqlitePool, SqlitePoolOptions},
 };
@@ -161,3 +162,32 @@ impl<T> NotFound for Result<T, sqlx::Error> {
         self.optional()?.ok_or_else(map)
     }
 }
+
+pub trait Duplicate {
+    type Ok;
+    type Error;
+
+    fn duplicate<E, F>(self, map: F) -> Result<Self::Ok, E>
+    where
+        E: From<Self::Error>,
+        F: FnOnce() -> E;
+}
+
+impl<T> Duplicate for Result<T, sqlx::Error> {
+    type Ok = T;
+    type Error = sqlx::Error;
+
+    fn duplicate<E, F>(self, map: F) -> Result<T, E>
+    where
+        E: From<sqlx::Error>,
+        F: FnOnce() -> E,
+    {
+        match self {
+            Ok(value) => Ok(value),
+            Err(error) => match error.as_database_error().map(DatabaseError::kind) {
+                Some(ErrorKind::UniqueViolation) => Err(map()),
+                _ => Err(error.into()),
+            },
+        }
+    }
+}