sqlite3_go18_test.go - external/github.com/mattn/go-sqlite3 - Git at Google

 // Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
 //
 // Use of this source code is governed by an MIT-style
 // license that can be found in the LICENSE file.

 //go:build go1.8 && cgo
 // +build go1.8,cgo

 package sqlite3

 import (
 	"context"
 	"database/sql"
 	"fmt"
 	"io/ioutil"
 	"math/rand"
 	"os"
 	"sync"
 	"testing"
 	"time"
 )

 func TestNamedParams(t *testing.T) {
 	tempFilename := TempFilename(t)
 	defer os.Remove(tempFilename)
 	db, err := sql.Open("sqlite3", tempFilename)
 	if err != nil {
 		t.Fatal("Failed to open database:", err)
 	}
 	defer db.Close()

 	_, err = db.Exec(`
 	create table foo (id integer, name text, extra text);
 	`)
 	if err != nil {
 		t.Error("Failed to call db.Query:", err)
 	}

 	_, err = db.Exec(`insert into foo(id, name, extra) values(:id, :name, :name)`, sql.Named("name", "foo"), sql.Named("id", 1))
 	if err != nil {
 		t.Error("Failed to call db.Exec:", err)
 	}

 	row := db.QueryRow(`select id, extra from foo where id = :id and extra = :extra`, sql.Named("id", 1), sql.Named("extra", "foo"))
 	if row == nil {
 		t.Error("Failed to call db.QueryRow")
 	}
 	var id int
 	var extra string
 	err = row.Scan(&id, &extra)
 	if err != nil {
 		t.Error("Failed to db.Scan:", err)
 	}
 	if id != 1 || extra != "foo" {
 		t.Error("Failed to db.QueryRow: not matched results")
 	}
 }

 var (
 	testTableStatements = []string{
 		`DROP TABLE IF EXISTS test_table`,
 		`
 CREATE TABLE IF NOT EXISTS test_table (
 	key1      VARCHAR(64) PRIMARY KEY,
 	key_id    VARCHAR(64) NOT NULL,
 	key2      VARCHAR(64) NOT NULL,
 	key3      VARCHAR(64) NOT NULL,
 	key4      VARCHAR(64) NOT NULL,
 	key5      VARCHAR(64) NOT NULL,
 	key6      VARCHAR(64) NOT NULL,
 	data      BLOB        NOT NULL
 );`,
 	}
 	letterBytes = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
 )

 func randStringBytes(n int) string {
 	b := make([]byte, n)
 	for i := range b {
 		b[i] = letterBytes[rand.Intn(len(letterBytes))]
 	}
 	return string(b)
 }

 func initDatabase(t *testing.T, db *sql.DB, rowCount int64) {
 	for _, query := range testTableStatements {
 		_, err := db.Exec(query)
 		if err != nil {
 			t.Fatal(err)
 		}
 	}
 	for i := int64(0); i < rowCount; i++ {
 		query := `INSERT INTO test_table
 			(key1, key_id, key2, key3, key4, key5, key6, data)
 			VALUES
 			(?, ?, ?, ?, ?, ?, ?, ?);`
 		args := []interface{}{
 			randStringBytes(50),
 			fmt.Sprint(i),
 			randStringBytes(50),
 			randStringBytes(50),
 			randStringBytes(50),
 			randStringBytes(50),
 			randStringBytes(50),
 			randStringBytes(50),
 			randStringBytes(2048),
 		}
 		_, err := db.Exec(query, args...)
 		if err != nil {
 			t.Fatal(err)
 		}
 	}
 }

 func TestShortTimeout(t *testing.T) {
 	srcTempFilename := TempFilename(t)
 	defer os.Remove(srcTempFilename)

 	db, err := sql.Open("sqlite3", srcTempFilename)
 	if err != nil {
 		t.Fatal(err)
 	}
 	defer db.Close()
 	initDatabase(t, db, 100)

 	ctx, cancel := context.WithTimeout(context.Background(), 1*time.Microsecond)
 	defer cancel()
 	query := `SELECT key1, key_id, key2, key3, key4, key5, key6, data
 		FROM test_table
 		ORDER BY key2 ASC`
 	_, err = db.QueryContext(ctx, query)
 	if err != nil && err != context.DeadlineExceeded {
 		t.Fatal(err)
 	}
 	if ctx.Err() != nil && ctx.Err() != context.DeadlineExceeded {
 		t.Fatal(ctx.Err())
 	}
 }

 func TestExecContextCancel(t *testing.T) {
 	srcTempFilename := TempFilename(t)
 	defer os.Remove(srcTempFilename)

 	db, err := sql.Open("sqlite3", srcTempFilename)
 	if err != nil {
 		t.Fatal(err)
 	}

 	defer db.Close()

 	ts := time.Now()
 	initDatabase(t, db, 1000)
 	spent := time.Since(ts)
 	const minTestTime = 100 * time.Millisecond
 	if spent < minTestTime {
 		t.Skipf("test will be too racy (spent=%s < min=%s) as ExecContext below will be too fast.",
 			spent.String(), minTestTime.String(),
 		)
 	}

 	// expected to be extremely slow query
 	q := `
 INSERT INTO test_table (key1, key_id, key2, key3, key4, key5, key6, data)
 SELECT t1.key1 || t2.key1, t1.key_id || t2.key_id, t1.key2 || t2.key2, t1.key3 || t2.key3, t1.key4 || t2.key4, t1.key5 || t2.key5, t1.key6 || t2.key6, t1.data || t2.data
 FROM test_table t1 LEFT OUTER JOIN test_table t2`
 	// expect query above take ~ same time as setup above
 	// This is racy: the context must be valid so sql/db.ExecContext calls the sqlite3 driver.
 	// It starts the query, the context expires, then calls sqlite3_interrupt
 	ctx, cancel := context.WithTimeout(context.Background(), minTestTime/2)
 	defer cancel()
 	ts = time.Now()
 	r, err := db.ExecContext(ctx, q)
 	// racy check
 	if r != nil {
 		n, err := r.RowsAffected()
 		t.Logf("query should not have succeeded: rows=%d; err=%v; duration=%s",
 			n, err, time.Since(ts).String())
 	}
 	if err != context.DeadlineExceeded {
 		t.Fatal(err, ctx.Err())
 	}
 }

 func TestQueryRowContextCancel(t *testing.T) {
 	srcTempFilename := TempFilename(t)
 	defer os.Remove(srcTempFilename)

 	db, err := sql.Open("sqlite3", srcTempFilename)
 	if err != nil {
 		t.Fatal(err)
 	}
 	defer db.Close()
 	initDatabase(t, db, 100)

 	const query = `SELECT key_id FROM test_table ORDER BY key2 ASC`
 	var keyID string
 	unexpectedErrors := make(map[string]int)
 	for i := 0; i < 10000; i++ {
 		ctx, cancel := context.WithCancel(context.Background())
 		row := db.QueryRowContext(ctx, query)

 		cancel()
 		// it is fine to get "nil" as context cancellation can be handled with delay
 		if err := row.Scan(&keyID); err != nil && err != context.Canceled {
 			if err.Error() == "sql: Rows are closed" {
 				// see https://github.com/golang/go/issues/24431
 				// fixed in 1.11.1 to properly return context error
 				continue
 			}
 			unexpectedErrors[err.Error()]++
 		}
 	}
 	for errText, count := range unexpectedErrors {
 		t.Error(errText, count)
 	}
 }

 func TestQueryRowContextCancelParallel(t *testing.T) {
 	srcTempFilename := TempFilename(t)
 	defer os.Remove(srcTempFilename)

 	db, err := sql.Open("sqlite3", srcTempFilename)
 	if err != nil {
 		t.Fatal(err)
 	}
 	db.SetMaxOpenConns(10)
 	db.SetMaxIdleConns(5)

 	defer db.Close()
 	initDatabase(t, db, 100)

 	const query = `SELECT key_id FROM test_table ORDER BY key2 ASC`
 	wg := sync.WaitGroup{}
 	defer wg.Wait()

 	testCtx, cancel := context.WithCancel(context.Background())
 	defer cancel()

 	for i := 0; i < 10; i++ {
 		wg.Add(1)
 		go func() {
 			defer wg.Done()

 			var keyID string
 			for {
 				select {
 				case <-testCtx.Done():
 					return
 				default:
 				}
 				ctx, cancel := context.WithCancel(context.Background())
 				row := db.QueryRowContext(ctx, query)

 				cancel()
 				_ = row.Scan(&keyID) // see TestQueryRowContextCancel
 			}
 		}()
 	}

 	var keyID string
 	for i := 0; i < 10000; i++ {
 		// note that testCtx is not cancelled during query execution
 		row := db.QueryRowContext(testCtx, query)

 		if err := row.Scan(&keyID); err != nil {
 			t.Fatal(i, err)
 		}
 	}
 }

 func TestExecCancel(t *testing.T) {
 	db, err := sql.Open("sqlite3", ":memory:")
 	if err != nil {
 		t.Fatal(err)
 	}
 	defer db.Close()

 	if _, err = db.Exec("create table foo (id integer primary key)"); err != nil {
 		t.Fatal(err)
 	}

 	for n := 0; n < 100; n++ {
 		ctx, cancel := context.WithCancel(context.Background())
 		_, err = db.ExecContext(ctx, "insert into foo (id) values (?)", n)
 		cancel()
 		if err != nil {
 			t.Fatal(err)
 		}
 	}
 }

 func doTestOpenContext(t *testing.T, option string) (string, error) {
 	tempFilename := TempFilename(t)
 	url := tempFilename + option

 	defer func() {
 		err := os.Remove(tempFilename)
 		if err != nil {
 			t.Error("temp file remove error:", err)
 		}
 	}()

 	db, err := sql.Open("sqlite3", url)
 	if err != nil {
 		return "Failed to open database:", err
 	}

 	defer func() {
 		err = db.Close()
 		if err != nil {
 			t.Error("db close error:", err)
 		}
 	}()

 	ctx, cancel := context.WithTimeout(context.Background(), 55*time.Second)
 	err = db.PingContext(ctx)
 	cancel()
 	if err != nil {
 		return "ping error:", err
 	}

 	ctx, cancel = context.WithTimeout(context.Background(), 55*time.Second)
 	_, err = db.ExecContext(ctx, "drop table foo")
 	cancel()
 	ctx, cancel = context.WithTimeout(context.Background(), 55*time.Second)
 	_, err = db.ExecContext(ctx, "create table foo (id integer)")
 	cancel()
 	if err != nil {
 		return "Failed to create table:", err
 	}

 	if stat, err := os.Stat(tempFilename); err != nil || stat.IsDir() {
 		return "Failed to create ./foo.db", nil
 	}

 	return "", nil
 }

 func TestOpenContext(t *testing.T) {
 	cases := map[string]bool{
 		"":                   true,
 		"?_txlock=immediate": true,
 		"?_txlock=deferred":  true,
 		"?_txlock=exclusive": true,
 		"?_txlock=bogus":     false,
 	}
 	for option, expectedPass := range cases {
 		result, err := doTestOpenContext(t, option)
 		if result == "" {
 			if !expectedPass {
 				errmsg := fmt.Sprintf("_txlock error not caught at dbOpen with option: %s", option)
 				t.Fatal(errmsg)
 			}
 		} else if expectedPass {
 			if err == nil {
 				t.Fatal(result)
 			} else {
 				t.Fatal(result, err)
 			}
 		}
 	}
 }

 func TestFileCopyTruncate(t *testing.T) {
 	var err error
 	tempFilename := TempFilename(t)

 	defer func() {
 		err = os.Remove(tempFilename)
 		if err != nil {
 			t.Error("temp file remove error:", err)
 		}
 	}()

 	db, err := sql.Open("sqlite3", tempFilename)
 	if err != nil {
 		t.Fatal("open error:", err)
 	}

 	defer func() {
 		err = db.Close()
 		if err != nil {
 			t.Error("db close error:", err)
 		}
 	}()

 	ctx, cancel := context.WithTimeout(context.Background(), 55*time.Second)
 	err = db.PingContext(ctx)
 	cancel()
 	if err != nil {
 		t.Fatal("ping error:", err)
 	}

 	ctx, cancel = context.WithTimeout(context.Background(), 55*time.Second)
 	_, err = db.ExecContext(ctx, "drop table foo")
 	cancel()
 	ctx, cancel = context.WithTimeout(context.Background(), 55*time.Second)
 	_, err = db.ExecContext(ctx, "create table foo (id integer)")
 	cancel()
 	if err != nil {
 		t.Fatal("create table error:", err)
 	}

 	// copy db to new file
 	var data []byte
 	data, err = ioutil.ReadFile(tempFilename)
 	if err != nil {
 		t.Fatal("read file error:", err)
 	}

 	var f *os.File
 	f, err = os.Create(tempFilename + "-db-copy")
 	if err != nil {
 		t.Fatal("create file error:", err)
 	}

 	defer func() {
 		err = os.Remove(tempFilename + "-db-copy")
 		if err != nil {
 			t.Error("temp file moved remove error:", err)
 		}
 	}()

 	_, err = f.Write(data)
 	if err != nil {
 		f.Close()
 		t.Fatal("write file error:", err)
 	}
 	err = f.Close()
 	if err != nil {
 		t.Fatal("close file error:", err)
 	}

 	// truncate current db file
 	f, err = os.OpenFile(tempFilename, os.O_WRONLY|os.O_TRUNC, 0666)
 	if err != nil {
 		t.Fatal("open file error:", err)
 	}
 	err = f.Close()
 	if err != nil {
 		t.Fatal("close file error:", err)
 	}

 	// test db after file truncate
 	ctx, cancel = context.WithTimeout(context.Background(), 55*time.Second)
 	err = db.PingContext(ctx)
 	cancel()
 	if err != nil {
 		t.Fatal("ping error:", err)
 	}

 	ctx, cancel = context.WithTimeout(context.Background(), 55*time.Second)
 	_, err = db.ExecContext(ctx, "drop table foo")
 	cancel()
 	if err == nil {
 		t.Fatal("drop table no error")
 	}

 	ctx, cancel = context.WithTimeout(context.Background(), 55*time.Second)
 	_, err = db.ExecContext(ctx, "create table foo (id integer)")
 	cancel()
 	if err != nil {
 		t.Fatal("create table error:", err)
 	}

 	err = db.Close()
 	if err != nil {
 		t.Error("db close error:", err)
 	}

 	// test copied file
 	db, err = sql.Open("sqlite3", tempFilename+"-db-copy")
 	if err != nil {
 		t.Fatal("open error:", err)
 	}

 	defer func() {
 		err = db.Close()
 		if err != nil {
 			t.Error("db close error:", err)
 		}
 	}()

 	ctx, cancel = context.WithTimeout(context.Background(), 55*time.Second)
 	err = db.PingContext(ctx)
 	cancel()
 	if err != nil {
 		t.Fatal("ping error:", err)
 	}

 	ctx, cancel = context.WithTimeout(context.Background(), 55*time.Second)
 	_, err = db.ExecContext(ctx, "drop table foo")
 	cancel()
 	if err != nil {
 		t.Fatal("drop table error:", err)
 	}

 	ctx, cancel = context.WithTimeout(context.Background(), 55*time.Second)
 	_, err = db.ExecContext(ctx, "create table foo (id integer)")
 	cancel()
 	if err != nil {
 		t.Fatal("create table error:", err)
 	}
 }
	// Copyright (C) 2019 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
	//
	// Use of this source code is governed by an MIT-style
	// license that can be found in the LICENSE file.

	//go:build go1.8 && cgo
	// +build go1.8,cgo

	package sqlite3

	import (
	"context"
	"database/sql"
	"fmt"
	"io/ioutil"
	"math/rand"
	"os"
	"sync"
	"testing"
	"time"
	)

	func TestNamedParams(t *testing.T) {
	tempFilename := TempFilename(t)
	defer os.Remove(tempFilename)
	db, err := sql.Open("sqlite3", tempFilename)
	if err != nil {
	t.Fatal("Failed to open database:", err)
	}
	defer db.Close()

	_, err = db.Exec(`
	create table foo (id integer, name text, extra text);
	`)
	if err != nil {
	t.Error("Failed to call db.Query:", err)
	}

	_, err = db.Exec(`insert into foo(id, name, extra) values(:id, :name, :name)`, sql.Named("name", "foo"), sql.Named("id", 1))
	if err != nil {
	t.Error("Failed to call db.Exec:", err)
	}

	row := db.QueryRow(`select id, extra from foo where id = :id and extra = :extra`, sql.Named("id", 1), sql.Named("extra", "foo"))
	if row == nil {
	t.Error("Failed to call db.QueryRow")
	}
	var id int
	var extra string
	err = row.Scan(&id, &extra)
	if err != nil {
	t.Error("Failed to db.Scan:", err)
	}
	if id != 1 \|\| extra != "foo" {
	t.Error("Failed to db.QueryRow: not matched results")
	}
	}

	var (
	testTableStatements = []string{
	`DROP TABLE IF EXISTS test_table`,
	`
	CREATE TABLE IF NOT EXISTS test_table (
	key1 VARCHAR(64) PRIMARY KEY,
	key_id VARCHAR(64) NOT NULL,
	key2 VARCHAR(64) NOT NULL,
	key3 VARCHAR(64) NOT NULL,
	key4 VARCHAR(64) NOT NULL,
	key5 VARCHAR(64) NOT NULL,
	key6 VARCHAR(64) NOT NULL,
	data BLOB NOT NULL
	);`,
	}
	letterBytes = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
	)

	func randStringBytes(n int) string {
	b := make([]byte, n)
	for i := range b {
	b[i] = letterBytes[rand.Intn(len(letterBytes))]
	}
	return string(b)
	}

	func initDatabase(t testing.T, db sql.DB, rowCount int64) {
	for _, query := range testTableStatements {
	_, err := db.Exec(query)
	if err != nil {
	t.Fatal(err)
	}
	}
	for i := int64(0); i < rowCount; i++ {
	query := `INSERT INTO test_table
	(key1, key_id, key2, key3, key4, key5, key6, data)
	VALUES
	(?, ?, ?, ?, ?, ?, ?, ?);`
	args := []interface{}{
	randStringBytes(50),
	fmt.Sprint(i),
	randStringBytes(50),
	randStringBytes(50),
	randStringBytes(50),
	randStringBytes(50),
	randStringBytes(50),
	randStringBytes(50),
	randStringBytes(2048),
	}
	_, err := db.Exec(query, args...)
	if err != nil {
	t.Fatal(err)
	}
	}
	}

	func TestShortTimeout(t *testing.T) {
	srcTempFilename := TempFilename(t)
	defer os.Remove(srcTempFilename)

	db, err := sql.Open("sqlite3", srcTempFilename)
	if err != nil {
	t.Fatal(err)
	}
	defer db.Close()
	initDatabase(t, db, 100)

	ctx, cancel := context.WithTimeout(context.Background(), 1*time.Microsecond)
	defer cancel()
	query := `SELECT key1, key_id, key2, key3, key4, key5, key6, data
	FROM test_table
	ORDER BY key2 ASC`
	_, err = db.QueryContext(ctx, query)
	if err != nil && err != context.DeadlineExceeded {
	t.Fatal(err)
	}
	if ctx.Err() != nil && ctx.Err() != context.DeadlineExceeded {
	t.Fatal(ctx.Err())
	}
	}

	func TestExecContextCancel(t *testing.T) {
	srcTempFilename := TempFilename(t)
	defer os.Remove(srcTempFilename)

	db, err := sql.Open("sqlite3", srcTempFilename)
	if err != nil {
	t.Fatal(err)
	}

	defer db.Close()

	ts := time.Now()
	initDatabase(t, db, 1000)
	spent := time.Since(ts)
	const minTestTime = 100 * time.Millisecond
	if spent < minTestTime {
	t.Skipf("test will be too racy (spent=%s < min=%s) as ExecContext below will be too fast.",
	spent.String(), minTestTime.String(),
	)
	}

	// expected to be extremely slow query
	q := `
	INSERT INTO test_table (key1, key_id, key2, key3, key4, key5, key6, data)
	SELECT t1.key1 \|\| t2.key1, t1.key_id \|\| t2.key_id, t1.key2 \|\| t2.key2, t1.key3 \|\| t2.key3, t1.key4 \|\| t2.key4, t1.key5 \|\| t2.key5, t1.key6 \|\| t2.key6, t1.data \|\| t2.data
	FROM test_table t1 LEFT OUTER JOIN test_table t2`
	// expect query above take ~ same time as setup above
	// This is racy: the context must be valid so sql/db.ExecContext calls the sqlite3 driver.
	// It starts the query, the context expires, then calls sqlite3_interrupt
	ctx, cancel := context.WithTimeout(context.Background(), minTestTime/2)
	defer cancel()
	ts = time.Now()
	r, err := db.ExecContext(ctx, q)
	// racy check
	if r != nil {
	n, err := r.RowsAffected()
	t.Logf("query should not have succeeded: rows=%d; err=%v; duration=%s",
	n, err, time.Since(ts).String())
	}
	if err != context.DeadlineExceeded {
	t.Fatal(err, ctx.Err())
	}
	}

	func TestQueryRowContextCancel(t *testing.T) {
	srcTempFilename := TempFilename(t)
	defer os.Remove(srcTempFilename)

	db, err := sql.Open("sqlite3", srcTempFilename)
	if err != nil {
	t.Fatal(err)
	}
	defer db.Close()
	initDatabase(t, db, 100)

	const query = `SELECT key_id FROM test_table ORDER BY key2 ASC`
	var keyID string
	unexpectedErrors := make(map[string]int)
	for i := 0; i < 10000; i++ {
	ctx, cancel := context.WithCancel(context.Background())
	row := db.QueryRowContext(ctx, query)

	cancel()
	// it is fine to get "nil" as context cancellation can be handled with delay
	if err := row.Scan(&keyID); err != nil && err != context.Canceled {
	if err.Error() == "sql: Rows are closed" {
	// see https://github.com/golang/go/issues/24431
	// fixed in 1.11.1 to properly return context error
	continue
	}
	unexpectedErrors[err.Error()]++
	}
	}
	for errText, count := range unexpectedErrors {
	t.Error(errText, count)
	}
	}

	func TestQueryRowContextCancelParallel(t *testing.T) {
	srcTempFilename := TempFilename(t)
	defer os.Remove(srcTempFilename)

	db, err := sql.Open("sqlite3", srcTempFilename)
	if err != nil {
	t.Fatal(err)
	}
	db.SetMaxOpenConns(10)
	db.SetMaxIdleConns(5)

	defer db.Close()
	initDatabase(t, db, 100)

	const query = `SELECT key_id FROM test_table ORDER BY key2 ASC`
	wg := sync.WaitGroup{}
	defer wg.Wait()

	testCtx, cancel := context.WithCancel(context.Background())
	defer cancel()

	for i := 0; i < 10; i++ {
	wg.Add(1)
	go func() {
	defer wg.Done()

	var keyID string
	for {
	select {
	case <-testCtx.Done():
	return
	default:
	}
	ctx, cancel := context.WithCancel(context.Background())
	row := db.QueryRowContext(ctx, query)

	cancel()
	_ = row.Scan(&keyID) // see TestQueryRowContextCancel
	}
	}()
	}

	var keyID string
	for i := 0; i < 10000; i++ {
	// note that testCtx is not cancelled during query execution
	row := db.QueryRowContext(testCtx, query)

	if err := row.Scan(&keyID); err != nil {
	t.Fatal(i, err)
	}
	}
	}

	func TestExecCancel(t *testing.T) {
	db, err := sql.Open("sqlite3", ":memory:")
	if err != nil {
	t.Fatal(err)
	}
	defer db.Close()

	if _, err = db.Exec("create table foo (id integer primary key)"); err != nil {
	t.Fatal(err)
	}

	for n := 0; n < 100; n++ {
	ctx, cancel := context.WithCancel(context.Background())
	_, err = db.ExecContext(ctx, "insert into foo (id) values (?)", n)
	cancel()
	if err != nil {
	t.Fatal(err)
	}
	}
	}

	func doTestOpenContext(t *testing.T, option string) (string, error) {
	tempFilename := TempFilename(t)
	url := tempFilename + option

	defer func() {
	err := os.Remove(tempFilename)
	if err != nil {
	t.Error("temp file remove error:", err)
	}
	}()

	db, err := sql.Open("sqlite3", url)
	if err != nil {
	return "Failed to open database:", err
	}

	defer func() {
	err = db.Close()
	if err != nil {
	t.Error("db close error:", err)
	}
	}()

	ctx, cancel := context.WithTimeout(context.Background(), 55*time.Second)
	err = db.PingContext(ctx)
	cancel()
	if err != nil {
	return "ping error:", err
	}

	ctx, cancel = context.WithTimeout(context.Background(), 55*time.Second)
	_, err = db.ExecContext(ctx, "drop table foo")
	cancel()
	ctx, cancel = context.WithTimeout(context.Background(), 55*time.Second)
	_, err = db.ExecContext(ctx, "create table foo (id integer)")
	cancel()
	if err != nil {
	return "Failed to create table:", err
	}

	if stat, err := os.Stat(tempFilename); err != nil \|\| stat.IsDir() {
	return "Failed to create ./foo.db", nil
	}

	return "", nil
	}

	func TestOpenContext(t *testing.T) {
	cases := map[string]bool{
	"": true,
	"?_txlock=immediate": true,
	"?_txlock=deferred": true,
	"?_txlock=exclusive": true,
	"?_txlock=bogus": false,
	}
	for option, expectedPass := range cases {
	result, err := doTestOpenContext(t, option)
	if result == "" {
	if !expectedPass {
	errmsg := fmt.Sprintf("_txlock error not caught at dbOpen with option: %s", option)
	t.Fatal(errmsg)
	}
	} else if expectedPass {
	if err == nil {
	t.Fatal(result)
	} else {
	t.Fatal(result, err)
	}
	}
	}
	}

	func TestFileCopyTruncate(t *testing.T) {
	var err error
	tempFilename := TempFilename(t)

	defer func() {
	err = os.Remove(tempFilename)
	if err != nil {
	t.Error("temp file remove error:", err)
	}
	}()

	db, err := sql.Open("sqlite3", tempFilename)
	if err != nil {
	t.Fatal("open error:", err)
	}

	defer func() {
	err = db.Close()
	if err != nil {
	t.Error("db close error:", err)
	}
	}()

	ctx, cancel := context.WithTimeout(context.Background(), 55*time.Second)
	err = db.PingContext(ctx)
	cancel()
	if err != nil {
	t.Fatal("ping error:", err)
	}

	ctx, cancel = context.WithTimeout(context.Background(), 55*time.Second)
	_, err = db.ExecContext(ctx, "drop table foo")
	cancel()
	ctx, cancel = context.WithTimeout(context.Background(), 55*time.Second)
	_, err = db.ExecContext(ctx, "create table foo (id integer)")
	cancel()
	if err != nil {
	t.Fatal("create table error:", err)
	}

	// copy db to new file
	var data []byte
	data, err = ioutil.ReadFile(tempFilename)
	if err != nil {
	t.Fatal("read file error:", err)
	}

	var f *os.File
	f, err = os.Create(tempFilename + "-db-copy")
	if err != nil {
	t.Fatal("create file error:", err)
	}

	defer func() {
	err = os.Remove(tempFilename + "-db-copy")
	if err != nil {
	t.Error("temp file moved remove error:", err)
	}
	}()

	_, err = f.Write(data)
	if err != nil {
	f.Close()
	t.Fatal("write file error:", err)
	}
	err = f.Close()
	if err != nil {
	t.Fatal("close file error:", err)
	}

	// truncate current db file
	f, err = os.OpenFile(tempFilename, os.O_WRONLY\|os.O_TRUNC, 0666)
	if err != nil {
	t.Fatal("open file error:", err)
	}
	err = f.Close()
	if err != nil {
	t.Fatal("close file error:", err)
	}

	// test db after file truncate
	ctx, cancel = context.WithTimeout(context.Background(), 55*time.Second)
	err = db.PingContext(ctx)
	cancel()
	if err != nil {
	t.Fatal("ping error:", err)
	}

	ctx, cancel = context.WithTimeout(context.Background(), 55*time.Second)
	_, err = db.ExecContext(ctx, "drop table foo")
	cancel()
	if err == nil {
	t.Fatal("drop table no error")
	}

	ctx, cancel = context.WithTimeout(context.Background(), 55*time.Second)
	_, err = db.ExecContext(ctx, "create table foo (id integer)")
	cancel()
	if err != nil {
	t.Fatal("create table error:", err)
	}

	err = db.Close()
	if err != nil {
	t.Error("db close error:", err)
	}

	// test copied file
	db, err = sql.Open("sqlite3", tempFilename+"-db-copy")
	if err != nil {
	t.Fatal("open error:", err)
	}

	defer func() {
	err = db.Close()
	if err != nil {
	t.Error("db close error:", err)
	}
	}()

	ctx, cancel = context.WithTimeout(context.Background(), 55*time.Second)
	err = db.PingContext(ctx)
	cancel()
	if err != nil {
	t.Fatal("ping error:", err)
	}

	ctx, cancel = context.WithTimeout(context.Background(), 55*time.Second)
	_, err = db.ExecContext(ctx, "drop table foo")
	cancel()
	if err != nil {
	t.Fatal("drop table error:", err)
	}

	ctx, cancel = context.WithTimeout(context.Background(), 55*time.Second)
	_, err = db.ExecContext(ctx, "create table foo (id integer)")
	cancel()
	if err != nil {
	t.Fatal("create table error:", err)
	}
	}