From d4027b013309a8f3d2895601163ec9e48bce5044 Mon Sep 17 00:00:00 2001
From: kim <grufwub@gmail.com>
Date: Fri, 19 Apr 2024 09:32:20 +0100
Subject: [PATCH] export the database/sql driver type and global instance

---
 driver/driver.go | 41 +++++++++++++++++++++++++++--------------
 1 file changed, 27 insertions(+), 14 deletions(-)

diff --git a/driver/driver.go b/driver/driver.go
index 19f5001..3264392 100644
--- a/driver/driver.go
+++ b/driver/driver.go
@@ -63,39 +63,52 @@ var driverName = "sqlite3"
 
 func init() {
 	if driverName != "" {
-		sql.Register(driverName, sqlite{})
+		sql.Register(driverName, &SQLiteDriver)
 	}
 }
 
+// SQLiteDriver is a global Driver{} instance
+// registered under [database/sql] as "sqlite3".
+var SQLiteDriver = Driver{}
+
 // Open opens the SQLite database specified by dataSourceName as a [database/sql.DB].
 //
 // The init function is called by the driver on new connections.
 // The conn can be used to execute queries, register functions, etc.
 // Any error return closes the conn and passes the error to [database/sql].
 func Open(dataSourceName string, init func(*sqlite3.Conn) error) (*sql.DB, error) {
-	c, err := newConnector(dataSourceName, init)
+	d := Driver{Init: init}
+	c, err := d.OpenConnector(dataSourceName)
 	if err != nil {
 		return nil, err
 	}
 	return sql.OpenDB(c), nil
 }
 
-type sqlite struct{}
+type Driver struct {
 
-func (sqlite) Open(name string) (driver.Conn, error) {
-	c, err := newConnector(name, nil)
+	// The init function is called by the driver on new connections.
+	// The conn can be used to execute queries, register functions, etc.
+	// Any error return closes the conn and passes the error to [database/sql].
+	Init func(*sqlite3.Conn) error
+}
+
+// Open: implements [database/sql.Driver].
+func (d *Driver) Open(name string) (driver.Conn, error) {
+	c, err := d.newConnector(name)
 	if err != nil {
 		return nil, err
 	}
 	return c.Connect(context.Background())
 }
 
-func (sqlite) OpenConnector(name string) (driver.Connector, error) {
-	return newConnector(name, nil)
+// OpenConnector: implements [database/sql.DriverContext].
+func (d *Driver) OpenConnector(name string) (driver.Connector, error) {
+	return d.newConnector(name)
 }
 
-func newConnector(name string, init func(*sqlite3.Conn) error) (*connector, error) {
-	c := connector{name: name, init: init}
+func (d *Driver) newConnector(name string) (*connector, error) {
+	c := connector{driver: d, name: name}
 
 	var txlock, timefmt string
 	if strings.HasPrefix(name, "file:") {
@@ -137,7 +150,7 @@ func newConnector(name string, init func(*sqlite3.Conn) error) (*connector, erro
 }
 
 type connector struct {
-	init    func(*sqlite3.Conn) error
+	driver  *Driver
 	name    string
 	txBegin string
 	tmRead  sqlite3.TimeFormat
@@ -146,7 +159,7 @@ type connector struct {
 }
 
 func (n *connector) Driver() driver.Driver {
-	return sqlite{}
+	return n.driver
 }
 
 func (n *connector) Connect(ctx context.Context) (_ driver.Conn, err error) {
@@ -175,13 +188,13 @@ func (n *connector) Connect(ctx context.Context) (_ driver.Conn, err error) {
 			return nil, err
 		}
 	}
-	if n.init != nil {
-		err = n.init(c.Conn)
+	if n.driver.Init != nil {
+		err = n.driver.Init(c.Conn)
 		if err != nil {
 			return nil, err
 		}
 	}
-	if n.pragmas || n.init != nil {
+	if n.pragmas || n.driver.Init != nil {
 		s, _, err := c.Conn.Prepare(`PRAGMA query_only`)
 		if err != nil {
 			return nil, err