move HasX types into the module where X is

sqlx-core/src/cursor.rs

@@ -2,9 +2,10 @@
 
 use futures_core::future::BoxFuture;
 
-use crate::database::{Database, HasRow};
+use crate::database::Database;
 use crate::executor::Execute;
 use crate::pool::Pool;
+use crate::row::HasRow;
 
 /// Represents a result set, which is generated by executing a query against the database.
 ///
@@ -70,3 +71,18 @@ where
 pub(crate) mod private {
     pub trait Sealed {}
 }
+
+/// Associate [`Database`] with a [`Cursor`] of a generic lifetime.
+///
+/// ---
+///
+/// The upcoming Rust feature, [Generic Associated Types], should obviate
+/// the need for this trait.
+///
+/// [Generic Associated Types]: https://www.google.com/search?q=generic+associated+types+rust&oq=generic+associated+types+rust&aqs=chrome..69i57j0l5.3327j0j7&sourceid=chrome&ie=UTF-8
+pub trait HasCursor<'c, 'q> {
+    type Database: Database;
+
+    /// The concrete `Cursor` implementation for this database.
+    type Cursor: Cursor<'c, 'q, Database = Self::Database>;
+}

sqlx-core/src/database.rs

@@ -2,10 +2,11 @@ use std::fmt::{Debug, Display};
 
 use crate::arguments::Arguments;
 use crate::connection::Connect;
-use crate::cursor::Cursor;
+use crate::cursor::HasCursor;
 use crate::error::DatabaseError;
-use crate::row::Row;
+use crate::row::HasRow;
 use crate::types::TypeInfo;
+use crate::value::HasRawValue;
 
 /// A database driver.
 ///
@@ -13,11 +14,10 @@ use crate::types::TypeInfo;
 /// database (e.g., **MySQL**, **Postgres**).
 pub trait Database
 where
-    Self: Sized + Send + 'static,
+    Self: Debug + Sized + Send + 'static,
     Self: for<'c> HasRow<'c, Database = Self>,
-    Self: for<'c> HasRawValue<'c>,
+    Self: for<'c> HasRawValue<'c, Database = Self>,
     Self: for<'c, 'q> HasCursor<'c, 'q, Database = Self>,
-    Self: Debug,
 {
     /// The concrete `Connection` implementation for this database.
     type Connection: Connect<Database = Self>;
@@ -33,55 +33,10 @@ where
 
     /// The Rust type used as the buffer when encoding arguments.
     ///
-    /// For example, **Postgres** and **MySQL** use `Vec<u8>`; however, **SQLite** uses `Vec<SqliteArgumentValue>`.
+    /// For example, **Postgres** and **MySQL** use `Vec<u8>`;
+    /// however, **SQLite** uses `Vec<SqliteArgumentValue>`.
     type RawBuffer: Default;
 
     /// The concrete `DatabaseError` type used to report errors from the database.
     type Error: DatabaseError + Send + Sync;
 }
-
-/// Associate [`Database`] with a `RawValue` of a generic lifetime.
-///
-/// ---
-///
-/// The upcoming Rust feature, [Generic Associated Types], should obviate
-/// the need for this trait.
-///
-/// [Generic Associated Types]: https://www.google.com/search?q=generic+associated+types+rust&oq=generic+associated+types+rust&aqs=chrome..69i57j0l5.3327j0j7&sourceid=chrome&ie=UTF-8
-pub trait HasRawValue<'c> {
-    /// The Rust type used to hold a not-yet-decoded value that has just been
-    /// received from the database.
-    ///
-    /// For example, **Postgres** and **MySQL** use `&'c [u8]`; however, **SQLite** uses `SqliteValue<'c>`.
-    type RawValue;
-}
-
-/// Associate [`Database`] with a [`Cursor`] of a generic lifetime.
-///
-/// ---
-///
-/// The upcoming Rust feature, [Generic Associated Types], should obviate
-/// the need for this trait.
-///
-/// [Generic Associated Types]: https://www.google.com/search?q=generic+associated+types+rust&oq=generic+associated+types+rust&aqs=chrome..69i57j0l5.3327j0j7&sourceid=chrome&ie=UTF-8
-pub trait HasCursor<'c, 'q> {
-    type Database: Database;
-
-    /// The concrete `Cursor` implementation for this database.
-    type Cursor: Cursor<'c, 'q, Database = Self::Database>;
-}
-
-/// Associate [`Database`] with a [`Row`] of a generic lifetime.
-///
-/// ---
-///
-/// The upcoming Rust feature, [Generic Associated Types], should obviate
-/// the need for this trait.
-///
-/// [Generic Associated Types]: https://www.google.com/search?q=generic+associated+types+rust&oq=generic+associated+types+rust&aqs=chrome..69i57j0l5.3327j0j7&sourceid=chrome&ie=UTF-8
-pub trait HasRow<'c> {
-    type Database: Database;
-
-    /// The concrete `Row` implementation for this database.
-    type Row: Row<'c, Database = Self::Database>;
-}

sqlx-core/src/decode.rs

@@ -1,6 +1,7 @@
 //! Types and traits for decoding values from the database.
 
-use crate::database::{Database, HasRawValue};
+use crate::database::Database;
+use crate::value::HasRawValue;
 
 /// A type that can be decoded from the database.
 pub trait Decode<'de, DB>

sqlx-core/src/executor.rs

@@ -1,6 +1,7 @@
 use futures_core::future::BoxFuture;
 
-use crate::database::{Database, HasCursor};
+use crate::cursor::HasCursor;
+use crate::database::Database;
 use crate::describe::Describe;
 
 /// A type that contains or can provide a database connection to use for executing queries

sqlx-core/src/lib.rs

@@ -25,6 +25,7 @@ mod io;
 pub mod connection;
 pub mod cursor;
 pub mod database;
+pub mod value;
 
 #[macro_use]
 pub mod executor;

sqlx-core/src/pool/executor.rs

@@ -2,8 +2,8 @@ use futures_core::future::BoxFuture;
 
 use super::PoolConnection;
 use crate::connection::Connect;
-use crate::cursor::Cursor;
-use crate::database::{Database, HasCursor};
+use crate::cursor::{Cursor, HasCursor};
+use crate::database::Database;
 use crate::describe::Describe;
 use crate::executor::Execute;
 use crate::executor::{Executor, RefExecutor};

sqlx-core/src/query.rs

@@ -6,10 +6,11 @@ use futures_util::future::ready;
 use futures_util::TryFutureExt;
 
 use crate::arguments::Arguments;
-use crate::cursor::Cursor;
-use crate::database::{Database, HasCursor, HasRow};
+use crate::cursor::{Cursor, HasCursor};
+use crate::database::Database;
 use crate::encode::Encode;
 use crate::executor::{Execute, Executor, RefExecutor};
+use crate::row::HasRow;
 use crate::types::Type;
 
 /// Raw SQL query with bind parameters. Returned by [`query`][crate::query::query].

sqlx-core/src/row.rs

@@ -1,8 +1,9 @@
 //! Contains the `ColumnIndex`, `Row`, and `FromRow` traits.
 
-use crate::database::{Database, HasRawValue};
+use crate::database::Database;
 use crate::decode::Decode;
 use crate::types::Type;
+use crate::value::HasRawValue;
 
 /// A type that can be used to index into a [`Row`].
 ///
@@ -149,6 +150,21 @@ pub(crate) mod private_row {
     pub trait Sealed {}
 }
 
+/// Associate [`Database`] with a [`Row`] of a generic lifetime.
+///
+/// ---
+///
+/// The upcoming Rust feature, [Generic Associated Types], should obviate
+/// the need for this trait.
+///
+/// [Generic Associated Types]: https://www.google.com/search?q=generic+associated+types+rust&oq=generic+associated+types+rust&aqs=chrome..69i57j0l5.3327j0j7&sourceid=chrome&ie=UTF-8
+pub trait HasRow<'c> {
+    type Database: Database;
+
+    /// The concrete `Row` implementation for this database.
+    type Row: Row<'c, Database = Self::Database>;
+}
+
 /// A record that can be built from a row returned by the database.
 ///
 /// In order to use [`query_as`] the output type must implement `FromRow`.
@@ -292,38 +308,6 @@ macro_rules! impl_map_row_for_row {
     };
 }
 
-#[allow(unused_macros)]
-macro_rules! impl_column_index_for_row {
-    ($R:ident) => {
-        impl<'c> crate::row::ColumnIndex<'c, $R<'c>> for usize {
-            fn index(
-                &self,
-                row: &$R<'c>,
-            ) -> crate::Result<<$R<'c> as crate::row::Row<'c>>::Database, usize> {
-                let len = crate::row::Row::len(row);
-
-                if *self >= len {
-                    return Err(crate::Error::ColumnIndexOutOfBounds { len, index: *self });
-                }
-
-                Ok(*self)
-            }
-        }
-
-        impl<'c> crate::row::ColumnIndex<'c, $R<'c>> for str {
-            fn index(
-                &self,
-                row: &$R<'c>,
-            ) -> crate::Result<<$R<'c> as crate::row::Row<'c>>::Database, usize> {
-                row.columns
-                    .get(self)
-                    .ok_or_else(|| crate::Error::ColumnNotFound((*self).into()))
-                    .map(|&index| index as usize)
-            }
-        }
-    };
-}
-
 #[allow(unused_macros)]
 macro_rules! impl_from_row_for_row {
     ($R:ident) => {

sqlx-core/src/transaction.rs

@@ -3,8 +3,8 @@ use std::ops::{Deref, DerefMut};
 use futures_core::future::BoxFuture;
 
 use crate::connection::Connection;
+use crate::cursor::HasCursor;
 use crate::database::Database;
-use crate::database::HasCursor;
 use crate::describe::Describe;
 use crate::executor::{Execute, Executor, RefExecutor};
 use crate::runtime::spawn;

sqlx-core/src/value.rs

@@ -0,0 +1,23 @@
+use crate::database::Database;
+
+/// Associate [`Database`] with a `RawValue` of a generic lifetime.
+///
+/// ---
+///
+/// The upcoming Rust feature, [Generic Associated Types], should obviate
+/// the need for this trait.
+///
+/// [Generic Associated Types]: https://www.google.com/search?q=generic+associated+types+rust&oq=generic+associated+types+rust&aqs=chrome..69i57j0l5.3327j0j7&sourceid=chrome&ie=UTF-8
+pub trait HasRawValue<'c> {
+    type Database: Database;
+
+    /// The Rust type used to hold a not-yet-decoded value that has just been
+    /// received from the database.
+    type RawValue: RawValue<'c, Database = Self::Database>;
+}
+
+pub trait RawValue<'c> {
+    type Database: Database;
+
+    fn type_info(&self) -> <Self::Database as Database>::TypeInfo;
+}