feat(core): add DatabaseError

sqlx-mysql/src/error.rs

@@ -0,0 +1,28 @@
+use std::error::Error as StdError;
+use std::fmt::{self, Display, Formatter};
+
+use sqlx_core::DatabaseError;
+
+use crate::protocol::ErrPacket;
+
+/// An error returned from the MySQL database server.
+#[allow(clippy::module_name_repetitions)]
+#[derive(Debug)]
+pub struct MySqlDatabaseError(pub(crate) ErrPacket);
+
+impl DatabaseError for MySqlDatabaseError {
+    fn message(&self) -> &str {
+        &self.0.error_message
+    }
+}
+
+impl Display for MySqlDatabaseError {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        match &self.0.sql_state {
+            Some(state) => write!(f, "{} ({}): {}", self.0.error_code, state, self.message()),
+            None => write!(f, "{}: {}", self.0.error_code, self.message()),
+        }
+    }
+}
+
+impl StdError for MySqlDatabaseError {}