Adding upstream version 1.21.8.upstream/1.21.8

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1283 insertions, 0 deletions

diff --git a/src/database/sql/fakedb_test.go b/src/database/sql/fakedb_test.go
new file mode 100644
index 0000000..cfeb3b3
--- /dev/null
+++ b/src/database/sql/fakedb_test.go
@@ -0,0 +1,1283 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package sql
+
+import (
+	"context"
+	"database/sql/driver"
+	"errors"
+	"fmt"
+	"io"
+	"reflect"
+	"sort"
+	"strconv"
+	"strings"
+	"sync"
+	"sync/atomic"
+	"testing"
+	"time"
+)
+
+// fakeDriver is a fake database that implements Go's driver.Driver
+// interface, just for testing.
+//
+// It speaks a query language that's semantically similar to but
+// syntactically different and simpler than SQL.  The syntax is as
+// follows:
+//
+//	WIPE
+//	CREATE|<tablename>|<col>=<type>,<col>=<type>,...
+//	  where types are: "string", [u]int{8,16,32,64}, "bool"
+//	INSERT|<tablename>|col=val,col2=val2,col3=?
+//	SELECT|<tablename>|projectcol1,projectcol2|filtercol=?,filtercol2=?
+//	SELECT|<tablename>|projectcol1,projectcol2|filtercol=?param1,filtercol2=?param2
+//
+// Any of these can be preceded by PANIC|<method>|, to cause the
+// named method on fakeStmt to panic.
+//
+// Any of these can be proceeded by WAIT|<duration>|, to cause the
+// named method on fakeStmt to sleep for the specified duration.
+//
+// Multiple of these can be combined when separated with a semicolon.
+//
+// When opening a fakeDriver's database, it starts empty with no
+// tables. All tables and data are stored in memory only.
+type fakeDriver struct {
+	mu         sync.Mutex // guards 3 following fields
+	openCount  int        // conn opens
+	closeCount int        // conn closes
+	waitCh     chan struct{}
+	waitingCh  chan struct{}
+	dbs        map[string]*fakeDB
+}
+
+type fakeConnector struct {
+	name string
+
+	waiter func(context.Context)
+	closed bool
+}
+
+func (c *fakeConnector) Connect(context.Context) (driver.Conn, error) {
+	conn, err := fdriver.Open(c.name)
+	conn.(*fakeConn).waiter = c.waiter
+	return conn, err
+}
+
+func (c *fakeConnector) Driver() driver.Driver {
+	return fdriver
+}
+
+func (c *fakeConnector) Close() error {
+	if c.closed {
+		return errors.New("fakedb: connector is closed")
+	}
+	c.closed = true
+	return nil
+}
+
+type fakeDriverCtx struct {
+	fakeDriver
+}
+
+var _ driver.DriverContext = &fakeDriverCtx{}
+
+func (cc *fakeDriverCtx) OpenConnector(name string) (driver.Connector, error) {
+	return &fakeConnector{name: name}, nil
+}
+
+type fakeDB struct {
+	name string
+
+	useRawBytes atomic.Bool
+
+	mu       sync.Mutex
+	tables   map[string]*table
+	badConn  bool
+	allowAny bool
+}
+
+type fakeError struct {
+	Message string
+	Wrapped error
+}
+
+func (err fakeError) Error() string {
+	return err.Message
+}
+
+func (err fakeError) Unwrap() error {
+	return err.Wrapped
+}
+
+type table struct {
+	mu      sync.Mutex
+	colname []string
+	coltype []string
+	rows    []*row
+}
+
+func (t *table) columnIndex(name string) int {
+	for n, nname := range t.colname {
+		if name == nname {
+			return n
+		}
+	}
+	return -1
+}
+
+type row struct {
+	cols []any // must be same size as its table colname + coltype
+}
+
+type memToucher interface {
+	// touchMem reads & writes some memory, to help find data races.
+	touchMem()
+}
+
+type fakeConn struct {
+	db *fakeDB // where to return ourselves to
+
+	currTx *fakeTx
+
+	// Every operation writes to line to enable the race detector
+	// check for data races.
+	line int64
+
+	// Stats for tests:
+	mu          sync.Mutex
+	stmtsMade   int
+	stmtsClosed int
+	numPrepare  int
+
+	// bad connection tests; see isBad()
+	bad       bool
+	stickyBad bool
+
+	skipDirtySession bool // tests that use Conn should set this to true.
+
+	// dirtySession tests ResetSession, true if a query has executed
+	// until ResetSession is called.
+	dirtySession bool
+
+	// The waiter is called before each query. May be used in place of the "WAIT"
+	// directive.
+	waiter func(context.Context)
+}
+
+func (c *fakeConn) touchMem() {
+	c.line++
+}
+
+func (c *fakeConn) incrStat(v *int) {
+	c.mu.Lock()
+	*v++
+	c.mu.Unlock()
+}
+
+type fakeTx struct {
+	c *fakeConn
+}
+
+type boundCol struct {
+	Column      string
+	Placeholder string
+	Ordinal     int
+}
+
+type fakeStmt struct {
+	memToucher
+	c *fakeConn
+	q string // just for debugging
+
+	cmd   string
+	table string
+	panic string
+	wait  time.Duration
+
+	next *fakeStmt // used for returning multiple results.
+
+	closed bool
+
+	colName      []string // used by CREATE, INSERT, SELECT (selected columns)
+	colType      []string // used by CREATE
+	colValue     []any    // used by INSERT (mix of strings and "?" for bound params)
+	placeholders int      // used by INSERT/SELECT: number of ? params
+
+	whereCol []boundCol // used by SELECT (all placeholders)
+
+	placeholderConverter []driver.ValueConverter // used by INSERT
+}
+
+var fdriver driver.Driver = &fakeDriver{}
+
+func init() {
+	Register("test", fdriver)
+}
+
+func contains(list []string, y string) bool {
+	for _, x := range list {
+		if x == y {
+			return true
+		}
+	}
+	return false
+}
+
+type Dummy struct {
+	driver.Driver
+}
+
+func TestDrivers(t *testing.T) {
+	unregisterAllDrivers()
+	Register("test", fdriver)
+	Register("invalid", Dummy{})
+	all := Drivers()
+	if len(all) < 2 || !sort.StringsAreSorted(all) || !contains(all, "test") || !contains(all, "invalid") {
+		t.Fatalf("Drivers = %v, want sorted list with at least [invalid, test]", all)
+	}
+}
+
+// hook to simulate connection failures
+var hookOpenErr struct {
+	sync.Mutex
+	fn func() error
+}
+
+func setHookOpenErr(fn func() error) {
+	hookOpenErr.Lock()
+	defer hookOpenErr.Unlock()
+	hookOpenErr.fn = fn
+}
+
+// Supports dsn forms:
+//
+//	<dbname>
+//	<dbname>;<opts>  (only currently supported option is `badConn`,
+//	                  which causes driver.ErrBadConn to be returned on
+//	                  every other conn.Begin())
+func (d *fakeDriver) Open(dsn string) (driver.Conn, error) {
+	hookOpenErr.Lock()
+	fn := hookOpenErr.fn
+	hookOpenErr.Unlock()
+	if fn != nil {
+		if err := fn(); err != nil {
+			return nil, err
+		}
+	}
+	parts := strings.Split(dsn, ";")
+	if len(parts) < 1 {
+		return nil, errors.New("fakedb: no database name")
+	}
+	name := parts[0]
+
+	db := d.getDB(name)
+
+	d.mu.Lock()
+	d.openCount++
+	d.mu.Unlock()
+	conn := &fakeConn{db: db}
+
+	if len(parts) >= 2 && parts[1] == "badConn" {
+		conn.bad = true
+	}
+	if d.waitCh != nil {
+		d.waitingCh <- struct{}{}
+		<-d.waitCh
+		d.waitCh = nil
+		d.waitingCh = nil
+	}
+	return conn, nil
+}
+
+func (d *fakeDriver) getDB(name string) *fakeDB {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	if d.dbs == nil {
+		d.dbs = make(map[string]*fakeDB)
+	}
+	db, ok := d.dbs[name]
+	if !ok {
+		db = &fakeDB{name: name}
+		d.dbs[name] = db
+	}
+	return db
+}
+
+func (db *fakeDB) wipe() {
+	db.mu.Lock()
+	defer db.mu.Unlock()
+	db.tables = nil
+}
+
+func (db *fakeDB) createTable(name string, columnNames, columnTypes []string) error {
+	db.mu.Lock()
+	defer db.mu.Unlock()
+	if db.tables == nil {
+		db.tables = make(map[string]*table)
+	}
+	if _, exist := db.tables[name]; exist {
+		return fmt.Errorf("fakedb: table %q already exists", name)
+	}
+	if len(columnNames) != len(columnTypes) {
+		return fmt.Errorf("fakedb: create table of %q len(names) != len(types): %d vs %d",
+			name, len(columnNames), len(columnTypes))
+	}
+	db.tables[name] = &table{colname: columnNames, coltype: columnTypes}
+	return nil
+}
+
+// must be called with db.mu lock held
+func (db *fakeDB) table(table string) (*table, bool) {
+	if db.tables == nil {
+		return nil, false
+	}
+	t, ok := db.tables[table]
+	return t, ok
+}
+
+func (db *fakeDB) columnType(table, column string) (typ string, ok bool) {
+	db.mu.Lock()
+	defer db.mu.Unlock()
+	t, ok := db.table(table)
+	if !ok {
+		return
+	}
+	for n, cname := range t.colname {
+		if cname == column {
+			return t.coltype[n], true
+		}
+	}
+	return "", false
+}
+
+func (c *fakeConn) isBad() bool {
+	if c.stickyBad {
+		return true
+	} else if c.bad {
+		if c.db == nil {
+			return false
+		}
+		// alternate between bad conn and not bad conn
+		c.db.badConn = !c.db.badConn
+		return c.db.badConn
+	} else {
+		return false
+	}
+}
+
+func (c *fakeConn) isDirtyAndMark() bool {
+	if c.skipDirtySession {
+		return false
+	}
+	if c.currTx != nil {
+		c.dirtySession = true
+		return false
+	}
+	if c.dirtySession {
+		return true
+	}
+	c.dirtySession = true
+	return false
+}
+
+func (c *fakeConn) Begin() (driver.Tx, error) {
+	if c.isBad() {
+		return nil, fakeError{Wrapped: driver.ErrBadConn}
+	}
+	if c.currTx != nil {
+		return nil, errors.New("fakedb: already in a transaction")
+	}
+	c.touchMem()
+	c.currTx = &fakeTx{c: c}
+	return c.currTx, nil
+}
+
+var hookPostCloseConn struct {
+	sync.Mutex
+	fn func(*fakeConn, error)
+}
+
+func setHookpostCloseConn(fn func(*fakeConn, error)) {
+	hookPostCloseConn.Lock()
+	defer hookPostCloseConn.Unlock()
+	hookPostCloseConn.fn = fn
+}
+
+var testStrictClose *testing.T
+
+// setStrictFakeConnClose sets the t to Errorf on when fakeConn.Close
+// fails to close. If nil, the check is disabled.
+func setStrictFakeConnClose(t *testing.T) {
+	testStrictClose = t
+}
+
+func (c *fakeConn) ResetSession(ctx context.Context) error {
+	c.dirtySession = false
+	c.currTx = nil
+	if c.isBad() {
+		return fakeError{Message: "Reset Session: bad conn", Wrapped: driver.ErrBadConn}
+	}
+	return nil
+}
+
+var _ driver.Validator = (*fakeConn)(nil)
+
+func (c *fakeConn) IsValid() bool {
+	return !c.isBad()
+}
+
+func (c *fakeConn) Close() (err error) {
+	drv := fdriver.(*fakeDriver)
+	defer func() {
+		if err != nil && testStrictClose != nil {
+			testStrictClose.Errorf("failed to close a test fakeConn: %v", err)
+		}
+		hookPostCloseConn.Lock()
+		fn := hookPostCloseConn.fn
+		hookPostCloseConn.Unlock()
+		if fn != nil {
+			fn(c, err)
+		}
+		if err == nil {
+			drv.mu.Lock()
+			drv.closeCount++
+			drv.mu.Unlock()
+		}
+	}()
+	c.touchMem()
+	if c.currTx != nil {
+		return errors.New("fakedb: can't close fakeConn; in a Transaction")
+	}
+	if c.db == nil {
+		return errors.New("fakedb: can't close fakeConn; already closed")
+	}
+	if c.stmtsMade > c.stmtsClosed {
+		return errors.New("fakedb: can't close; dangling statement(s)")
+	}
+	c.db = nil
+	return nil
+}
+
+func checkSubsetTypes(allowAny bool, args []driver.NamedValue) error {
+	for _, arg := range args {
+		switch arg.Value.(type) {
+		case int64, float64, bool, nil, []byte, string, time.Time:
+		default:
+			if !allowAny {
+				return fmt.Errorf("fakedb: invalid argument ordinal %[1]d: %[2]v, type %[2]T", arg.Ordinal, arg.Value)
+			}
+		}
+	}
+	return nil
+}
+
+func (c *fakeConn) Exec(query string, args []driver.Value) (driver.Result, error) {
+	// Ensure that ExecContext is called if available.
+	panic("ExecContext was not called.")
+}
+
+func (c *fakeConn) ExecContext(ctx context.Context, query string, args []driver.NamedValue) (driver.Result, error) {
+	// This is an optional interface, but it's implemented here
+	// just to check that all the args are of the proper types.
+	// ErrSkip is returned so the caller acts as if we didn't
+	// implement this at all.
+	err := checkSubsetTypes(c.db.allowAny, args)
+	if err != nil {
+		return nil, err
+	}
+	return nil, driver.ErrSkip
+}
+
+func (c *fakeConn) Query(query string, args []driver.Value) (driver.Rows, error) {
+	// Ensure that ExecContext is called if available.
+	panic("QueryContext was not called.")
+}
+
+func (c *fakeConn) QueryContext(ctx context.Context, query string, args []driver.NamedValue) (driver.Rows, error) {
+	// This is an optional interface, but it's implemented here
+	// just to check that all the args are of the proper types.
+	// ErrSkip is returned so the caller acts as if we didn't
+	// implement this at all.
+	err := checkSubsetTypes(c.db.allowAny, args)
+	if err != nil {
+		return nil, err
+	}
+	return nil, driver.ErrSkip
+}
+
+func errf(msg string, args ...any) error {
+	return errors.New("fakedb: " + fmt.Sprintf(msg, args...))
+}
+
+// parts are table|selectCol1,selectCol2|whereCol=?,whereCol2=?
+// (note that where columns must always contain ? marks,
+// just a limitation for fakedb)
+func (c *fakeConn) prepareSelect(stmt *fakeStmt, parts []string) (*fakeStmt, error) {
+	if len(parts) != 3 {
+		stmt.Close()
+		return nil, errf("invalid SELECT syntax with %d parts; want 3", len(parts))
+	}
+	stmt.table = parts[0]
+
+	stmt.colName = strings.Split(parts[1], ",")
+	for n, colspec := range strings.Split(parts[2], ",") {
+		if colspec == "" {
+			continue
+		}
+		nameVal := strings.Split(colspec, "=")
+		if len(nameVal) != 2 {
+			stmt.Close()
+			return nil, errf("SELECT on table %q has invalid column spec of %q (index %d)", stmt.table, colspec, n)
+		}
+		column, value := nameVal[0], nameVal[1]
+		_, ok := c.db.columnType(stmt.table, column)
+		if !ok {
+			stmt.Close()
+			return nil, errf("SELECT on table %q references non-existent column %q", stmt.table, column)
+		}
+		if !strings.HasPrefix(value, "?") {
+			stmt.Close()
+			return nil, errf("SELECT on table %q has pre-bound value for where column %q; need a question mark",
+				stmt.table, column)
+		}
+		stmt.placeholders++
+		stmt.whereCol = append(stmt.whereCol, boundCol{Column: column, Placeholder: value, Ordinal: stmt.placeholders})
+	}
+	return stmt, nil
+}
+
+// parts are table|col=type,col2=type2
+func (c *fakeConn) prepareCreate(stmt *fakeStmt, parts []string) (*fakeStmt, error) {
+	if len(parts) != 2 {
+		stmt.Close()
+		return nil, errf("invalid CREATE syntax with %d parts; want 2", len(parts))
+	}
+	stmt.table = parts[0]
+	for n, colspec := range strings.Split(parts[1], ",") {
+		nameType := strings.Split(colspec, "=")
+		if len(nameType) != 2 {
+			stmt.Close()
+			return nil, errf("CREATE table %q has invalid column spec of %q (index %d)", stmt.table, colspec, n)
+		}
+		stmt.colName = append(stmt.colName, nameType[0])
+		stmt.colType = append(stmt.colType, nameType[1])
+	}
+	return stmt, nil
+}
+
+// parts are table|col=?,col2=val
+func (c *fakeConn) prepareInsert(ctx context.Context, stmt *fakeStmt, parts []string) (*fakeStmt, error) {
+	if len(parts) != 2 {
+		stmt.Close()
+		return nil, errf("invalid INSERT syntax with %d parts; want 2", len(parts))
+	}
+	stmt.table = parts[0]
+	for n, colspec := range strings.Split(parts[1], ",") {
+		nameVal := strings.Split(colspec, "=")
+		if len(nameVal) != 2 {
+			stmt.Close()
+			return nil, errf("INSERT table %q has invalid column spec of %q (index %d)", stmt.table, colspec, n)
+		}
+		column, value := nameVal[0], nameVal[1]
+		ctype, ok := c.db.columnType(stmt.table, column)
+		if !ok {
+			stmt.Close()
+			return nil, errf("INSERT table %q references non-existent column %q", stmt.table, column)
+		}
+		stmt.colName = append(stmt.colName, column)
+
+		if !strings.HasPrefix(value, "?") {
+			var subsetVal any
+			// Convert to driver subset type
+			switch ctype {
+			case "string":
+				subsetVal = []byte(value)
+			case "blob":
+				subsetVal = []byte(value)
+			case "int32":
+				i, err := strconv.Atoi(value)
+				if err != nil {
+					stmt.Close()
+					return nil, errf("invalid conversion to int32 from %q", value)
+				}
+				subsetVal = int64(i) // int64 is a subset type, but not int32
+			case "table": // For testing cursor reads.
+				c.skipDirtySession = true
+				vparts := strings.Split(value, "!")
+
+				substmt, err := c.PrepareContext(ctx, fmt.Sprintf("SELECT|%s|%s|", vparts[0], strings.Join(vparts[1:], ",")))
+				if err != nil {
+					return nil, err
+				}
+				cursor, err := (substmt.(driver.StmtQueryContext)).QueryContext(ctx, []driver.NamedValue{})
+				substmt.Close()
+				if err != nil {
+					return nil, err
+				}
+				subsetVal = cursor
+			default:
+				stmt.Close()
+				return nil, errf("unsupported conversion for pre-bound parameter %q to type %q", value, ctype)
+			}
+			stmt.colValue = append(stmt.colValue, subsetVal)
+		} else {
+			stmt.placeholders++
+			stmt.placeholderConverter = append(stmt.placeholderConverter, converterForType(ctype))
+			stmt.colValue = append(stmt.colValue, value)
+		}
+	}
+	return stmt, nil
+}
+
+// hook to simulate broken connections
+var hookPrepareBadConn func() bool
+
+func (c *fakeConn) Prepare(query string) (driver.Stmt, error) {
+	panic("use PrepareContext")
+}
+
+func (c *fakeConn) PrepareContext(ctx context.Context, query string) (driver.Stmt, error) {
+	c.numPrepare++
+	if c.db == nil {
+		panic("nil c.db; conn = " + fmt.Sprintf("%#v", c))
+	}
+
+	if c.stickyBad || (hookPrepareBadConn != nil && hookPrepareBadConn()) {
+		return nil, fakeError{Message: "Prepare: Sticky Bad", Wrapped: driver.ErrBadConn}
+	}
+
+	c.touchMem()
+	var firstStmt, prev *fakeStmt
+	for _, query := range strings.Split(query, ";") {
+		parts := strings.Split(query, "|")
+		if len(parts) < 1 {
+			return nil, errf("empty query")
+		}
+		stmt := &fakeStmt{q: query, c: c, memToucher: c}
+		if firstStmt == nil {
+			firstStmt = stmt
+		}
+		if len(parts) >= 3 {
+			switch parts[0] {
+			case "PANIC":
+				stmt.panic = parts[1]
+				parts = parts[2:]
+			case "WAIT":
+				wait, err := time.ParseDuration(parts[1])
+				if err != nil {
+					return nil, errf("expected section after WAIT to be a duration, got %q %v", parts[1], err)
+				}
+				parts = parts[2:]
+				stmt.wait = wait
+			}
+		}
+		cmd := parts[0]
+		stmt.cmd = cmd
+		parts = parts[1:]
+
+		if c.waiter != nil {
+			c.waiter(ctx)
+			if err := ctx.Err(); err != nil {
+				return nil, err
+			}
+		}
+
+		if stmt.wait > 0 {
+			wait := time.NewTimer(stmt.wait)
+			select {
+			case <-wait.C:
+			case <-ctx.Done():
+				wait.Stop()
+				return nil, ctx.Err()
+			}
+		}
+
+		c.incrStat(&c.stmtsMade)
+		var err error
+		switch cmd {
+		case "WIPE":
+			// Nothing
+		case "USE_RAWBYTES":
+			c.db.useRawBytes.Store(true)
+		case "SELECT":
+			stmt, err = c.prepareSelect(stmt, parts)
+		case "CREATE":
+			stmt, err = c.prepareCreate(stmt, parts)
+		case "INSERT":
+			stmt, err = c.prepareInsert(ctx, stmt, parts)
+		case "NOSERT":
+			// Do all the prep-work like for an INSERT but don't actually insert the row.
+			// Used for some of the concurrent tests.
+			stmt, err = c.prepareInsert(ctx, stmt, parts)
+		default:
+			stmt.Close()
+			return nil, errf("unsupported command type %q", cmd)
+		}
+		if err != nil {
+			return nil, err
+		}
+		if prev != nil {
+			prev.next = stmt
+		}
+		prev = stmt
+	}
+	return firstStmt, nil
+}
+
+func (s *fakeStmt) ColumnConverter(idx int) driver.ValueConverter {
+	if s.panic == "ColumnConverter" {
+		panic(s.panic)
+	}
+	if len(s.placeholderConverter) == 0 {
+		return driver.DefaultParameterConverter
+	}
+	return s.placeholderConverter[idx]
+}
+
+func (s *fakeStmt) Close() error {
+	if s.panic == "Close" {
+		panic(s.panic)
+	}
+	if s.c == nil {
+		panic("nil conn in fakeStmt.Close")
+	}
+	if s.c.db == nil {
+		panic("in fakeStmt.Close, conn's db is nil (already closed)")
+	}
+	s.touchMem()
+	if !s.closed {
+		s.c.incrStat(&s.c.stmtsClosed)
+		s.closed = true
+	}
+	if s.next != nil {
+		s.next.Close()
+	}
+	return nil
+}
+
+var errClosed = errors.New("fakedb: statement has been closed")
+
+// hook to simulate broken connections
+var hookExecBadConn func() bool
+
+func (s *fakeStmt) Exec(args []driver.Value) (driver.Result, error) {
+	panic("Using ExecContext")
+}
+
+var errFakeConnSessionDirty = errors.New("fakedb: session is dirty")
+
+func (s *fakeStmt) ExecContext(ctx context.Context, args []driver.NamedValue) (driver.Result, error) {
+	if s.panic == "Exec" {
+		panic(s.panic)
+	}
+	if s.closed {
+		return nil, errClosed
+	}
+
+	if s.c.stickyBad || (hookExecBadConn != nil && hookExecBadConn()) {
+		return nil, fakeError{Message: "Exec: Sticky Bad", Wrapped: driver.ErrBadConn}
+	}
+	if s.c.isDirtyAndMark() {
+		return nil, errFakeConnSessionDirty
+	}
+
+	err := checkSubsetTypes(s.c.db.allowAny, args)
+	if err != nil {
+		return nil, err
+	}
+	s.touchMem()
+
+	if s.wait > 0 {
+		time.Sleep(s.wait)
+	}
+
+	select {
+	default:
+	case <-ctx.Done():
+		return nil, ctx.Err()
+	}
+
+	db := s.c.db
+	switch s.cmd {
+	case "WIPE":
+		db.wipe()
+		return driver.ResultNoRows, nil
+	case "USE_RAWBYTES":
+		s.c.db.useRawBytes.Store(true)
+		return driver.ResultNoRows, nil
+	case "CREATE":
+		if err := db.createTable(s.table, s.colName, s.colType); err != nil {
+			return nil, err
+		}
+		return driver.ResultNoRows, nil
+	case "INSERT":
+		return s.execInsert(args, true)
+	case "NOSERT":
+		// Do all the prep-work like for an INSERT but don't actually insert the row.
+		// Used for some of the concurrent tests.
+		return s.execInsert(args, false)
+	}
+	return nil, fmt.Errorf("fakedb: unimplemented statement Exec command type of %q", s.cmd)
+}
+
+// When doInsert is true, add the row to the table.
+// When doInsert is false do prep-work and error checking, but don't
+// actually add the row to the table.
+func (s *fakeStmt) execInsert(args []driver.NamedValue, doInsert bool) (driver.Result, error) {
+	db := s.c.db
+	if len(args) != s.placeholders {
+		panic("error in pkg db; should only get here if size is correct")
+	}
+	db.mu.Lock()
+	t, ok := db.table(s.table)
+	db.mu.Unlock()
+	if !ok {
+		return nil, fmt.Errorf("fakedb: table %q doesn't exist", s.table)
+	}
+
+	t.mu.Lock()
+	defer t.mu.Unlock()
+
+	var cols []any
+	if doInsert {
+		cols = make([]any, len(t.colname))
+	}
+	argPos := 0
+	for n, colname := range s.colName {
+		colidx := t.columnIndex(colname)
+		if colidx == -1 {
+			return nil, fmt.Errorf("fakedb: column %q doesn't exist or dropped since prepared statement was created", colname)
+		}
+		var val any
+		if strvalue, ok := s.colValue[n].(string); ok && strings.HasPrefix(strvalue, "?") {
+			if strvalue == "?" {
+				val = args[argPos].Value
+			} else {
+				// Assign value from argument placeholder name.
+				for _, a := range args {
+					if a.Name == strvalue[1:] {
+						val = a.Value
+						break
+					}
+				}
+			}
+			argPos++
+		} else {
+			val = s.colValue[n]
+		}
+		if doInsert {
+			cols[colidx] = val
+		}
+	}
+
+	if doInsert {
+		t.rows = append(t.rows, &row{cols: cols})
+	}
+	return driver.RowsAffected(1), nil
+}
+
+// hook to simulate broken connections
+var hookQueryBadConn func() bool
+
+func (s *fakeStmt) Query(args []driver.Value) (driver.Rows, error) {
+	panic("Use QueryContext")
+}
+
+func (s *fakeStmt) QueryContext(ctx context.Context, args []driver.NamedValue) (driver.Rows, error) {
+	if s.panic == "Query" {
+		panic(s.panic)
+	}
+	if s.closed {
+		return nil, errClosed
+	}
+
+	if s.c.stickyBad || (hookQueryBadConn != nil && hookQueryBadConn()) {
+		return nil, fakeError{Message: "Query: Sticky Bad", Wrapped: driver.ErrBadConn}
+	}
+	if s.c.isDirtyAndMark() {
+		return nil, errFakeConnSessionDirty
+	}
+
+	err := checkSubsetTypes(s.c.db.allowAny, args)
+	if err != nil {
+		return nil, err
+	}
+
+	s.touchMem()
+	db := s.c.db
+	if len(args) != s.placeholders {
+		panic("error in pkg db; should only get here if size is correct")
+	}
+
+	setMRows := make([][]*row, 0, 1)
+	setColumns := make([][]string, 0, 1)
+	setColType := make([][]string, 0, 1)
+
+	for {
+		db.mu.Lock()
+		t, ok := db.table(s.table)
+		db.mu.Unlock()
+		if !ok {
+			return nil, fmt.Errorf("fakedb: table %q doesn't exist", s.table)
+		}
+
+		if s.table == "magicquery" {
+			if len(s.whereCol) == 2 && s.whereCol[0].Column == "op" && s.whereCol[1].Column == "millis" {
+				if args[0].Value == "sleep" {
+					time.Sleep(time.Duration(args[1].Value.(int64)) * time.Millisecond)
+				}
+			}
+		}
+		if s.table == "tx_status" && s.colName[0] == "tx_status" {
+			txStatus := "autocommit"
+			if s.c.currTx != nil {
+				txStatus = "transaction"
+			}
+			cursor := &rowsCursor{
+				db:        s.c.db,
+				parentMem: s.c,
+				posRow:    -1,
+				rows: [][]*row{
+					{
+						{
+							cols: []any{
+								txStatus,
+							},
+						},
+					},
+				},
+				cols: [][]string{
+					{
+						"tx_status",
+					},
+				},
+				colType: [][]string{
+					{
+						"string",
+					},
+				},
+				errPos: -1,
+			}
+			return cursor, nil
+		}
+
+		t.mu.Lock()
+
+		colIdx := make(map[string]int) // select column name -> column index in table
+		for _, name := range s.colName {
+			idx := t.columnIndex(name)
+			if idx == -1 {
+				t.mu.Unlock()
+				return nil, fmt.Errorf("fakedb: unknown column name %q", name)
+			}
+			colIdx[name] = idx
+		}
+
+		mrows := []*row{}
+	rows:
+		for _, trow := range t.rows {
+			// Process the where clause, skipping non-match rows. This is lazy
+			// and just uses fmt.Sprintf("%v") to test equality. Good enough
+			// for test code.
+			for _, wcol := range s.whereCol {
+				idx := t.columnIndex(wcol.Column)
+				if idx == -1 {
+					t.mu.Unlock()
+					return nil, fmt.Errorf("fakedb: invalid where clause column %q", wcol)
+				}
+				tcol := trow.cols[idx]
+				if bs, ok := tcol.([]byte); ok {
+					// lazy hack to avoid sprintf %v on a []byte
+					tcol = string(bs)
+				}
+				var argValue any
+				if wcol.Placeholder == "?" {
+					argValue = args[wcol.Ordinal-1].Value
+				} else {
+					// Assign arg value from placeholder name.
+					for _, a := range args {
+						if a.Name == wcol.Placeholder[1:] {
+							argValue = a.Value
+							break
+						}
+					}
+				}
+				if fmt.Sprintf("%v", tcol) != fmt.Sprintf("%v", argValue) {
+					continue rows
+				}
+			}
+			mrow := &row{cols: make([]any, len(s.colName))}
+			for seli, name := range s.colName {
+				mrow.cols[seli] = trow.cols[colIdx[name]]
+			}
+			mrows = append(mrows, mrow)
+		}
+
+		var colType []string
+		for _, column := range s.colName {
+			colType = append(colType, t.coltype[t.columnIndex(column)])
+		}
+
+		t.mu.Unlock()
+
+		setMRows = append(setMRows, mrows)
+		setColumns = append(setColumns, s.colName)
+		setColType = append(setColType, colType)
+
+		if s.next == nil {
+			break
+		}
+		s = s.next
+	}
+
+	cursor := &rowsCursor{
+		db:        s.c.db,
+		parentMem: s.c,
+		posRow:    -1,
+		rows:      setMRows,
+		cols:      setColumns,
+		colType:   setColType,
+		errPos:    -1,
+	}
+	return cursor, nil
+}
+
+func (s *fakeStmt) NumInput() int {
+	if s.panic == "NumInput" {
+		panic(s.panic)
+	}
+	return s.placeholders
+}
+
+// hook to simulate broken connections
+var hookCommitBadConn func() bool
+
+func (tx *fakeTx) Commit() error {
+	tx.c.currTx = nil
+	if hookCommitBadConn != nil && hookCommitBadConn() {
+		return fakeError{Message: "Commit: Hook Bad Conn", Wrapped: driver.ErrBadConn}
+	}
+	tx.c.touchMem()
+	return nil
+}
+
+// hook to simulate broken connections
+var hookRollbackBadConn func() bool
+
+func (tx *fakeTx) Rollback() error {
+	tx.c.currTx = nil
+	if hookRollbackBadConn != nil && hookRollbackBadConn() {
+		return fakeError{Message: "Rollback: Hook Bad Conn", Wrapped: driver.ErrBadConn}
+	}
+	tx.c.touchMem()
+	return nil
+}
+
+type rowsCursor struct {
+	db        *fakeDB
+	parentMem memToucher
+	cols      [][]string
+	colType   [][]string
+	posSet    int
+	posRow    int
+	rows      [][]*row
+	closed    bool
+
+	// errPos and err are for making Next return early with error.
+	errPos int
+	err    error
+
+	// a clone of slices to give out to clients, indexed by the
+	// original slice's first byte address.  we clone them
+	// just so we're able to corrupt them on close.
+	bytesClone map[*byte][]byte
+
+	// Every operation writes to line to enable the race detector
+	// check for data races.
+	// This is separate from the fakeConn.line to allow for drivers that
+	// can start multiple queries on the same transaction at the same time.
+	line int64
+
+	// closeErr is returned when rowsCursor.Close
+	closeErr error
+}
+
+func (rc *rowsCursor) touchMem() {
+	rc.parentMem.touchMem()
+	rc.line++
+}
+
+func (rc *rowsCursor) Close() error {
+	rc.touchMem()
+	rc.parentMem.touchMem()
+	rc.closed = true
+	return rc.closeErr
+}
+
+func (rc *rowsCursor) Columns() []string {
+	return rc.cols[rc.posSet]
+}
+
+func (rc *rowsCursor) ColumnTypeScanType(index int) reflect.Type {
+	return colTypeToReflectType(rc.colType[rc.posSet][index])
+}
+
+var rowsCursorNextHook func(dest []driver.Value) error
+
+func (rc *rowsCursor) Next(dest []driver.Value) error {
+	if rowsCursorNextHook != nil {
+		return rowsCursorNextHook(dest)
+	}
+
+	if rc.closed {
+		return errors.New("fakedb: cursor is closed")
+	}
+	rc.touchMem()
+	rc.posRow++
+	if rc.posRow == rc.errPos {
+		return rc.err
+	}
+	if rc.posRow >= len(rc.rows[rc.posSet]) {
+		return io.EOF // per interface spec
+	}
+	for i, v := range rc.rows[rc.posSet][rc.posRow].cols {
+		// TODO(bradfitz): convert to subset types? naah, I
+		// think the subset types should only be input to
+		// driver, but the sql package should be able to handle
+		// a wider range of types coming out of drivers. all
+		// for ease of drivers, and to prevent drivers from
+		// messing up conversions or doing them differently.
+		dest[i] = v
+
+		if bs, ok := v.([]byte); ok && !rc.db.useRawBytes.Load() {
+			if rc.bytesClone == nil {
+				rc.bytesClone = make(map[*byte][]byte)
+			}
+			clone, ok := rc.bytesClone[&bs[0]]
+			if !ok {
+				clone = make([]byte, len(bs))
+				copy(clone, bs)
+				rc.bytesClone[&bs[0]] = clone
+			}
+			dest[i] = clone
+		}
+	}
+	return nil
+}
+
+func (rc *rowsCursor) HasNextResultSet() bool {
+	rc.touchMem()
+	return rc.posSet < len(rc.rows)-1
+}
+
+func (rc *rowsCursor) NextResultSet() error {
+	rc.touchMem()
+	if rc.HasNextResultSet() {
+		rc.posSet++
+		rc.posRow = -1
+		return nil
+	}
+	return io.EOF // Per interface spec.
+}
+
+// fakeDriverString is like driver.String, but indirects pointers like
+// DefaultValueConverter.
+//
+// This could be surprising behavior to retroactively apply to
+// driver.String now that Go1 is out, but this is convenient for
+// our TestPointerParamsAndScans.
+type fakeDriverString struct{}
+
+func (fakeDriverString) ConvertValue(v any) (driver.Value, error) {
+	switch c := v.(type) {
+	case string, []byte:
+		return v, nil
+	case *string:
+		if c == nil {
+			return nil, nil
+		}
+		return *c, nil
+	}
+	return fmt.Sprintf("%v", v), nil
+}
+
+type anyTypeConverter struct{}
+
+func (anyTypeConverter) ConvertValue(v any) (driver.Value, error) {
+	return v, nil
+}
+
+func converterForType(typ string) driver.ValueConverter {
+	switch typ {
+	case "bool":
+		return driver.Bool
+	case "nullbool":
+		return driver.Null{Converter: driver.Bool}
+	case "byte", "int16":
+		return driver.NotNull{Converter: driver.DefaultParameterConverter}
+	case "int32":
+		return driver.Int32
+	case "nullbyte", "nullint32", "nullint16":
+		return driver.Null{Converter: driver.DefaultParameterConverter}
+	case "string":
+		return driver.NotNull{Converter: fakeDriverString{}}
+	case "nullstring":
+		return driver.Null{Converter: fakeDriverString{}}
+	case "int64":
+		// TODO(coopernurse): add type-specific converter
+		return driver.NotNull{Converter: driver.DefaultParameterConverter}
+	case "nullint64":
+		// TODO(coopernurse): add type-specific converter
+		return driver.Null{Converter: driver.DefaultParameterConverter}
+	case "float64":
+		// TODO(coopernurse): add type-specific converter
+		return driver.NotNull{Converter: driver.DefaultParameterConverter}
+	case "nullfloat64":
+		// TODO(coopernurse): add type-specific converter
+		return driver.Null{Converter: driver.DefaultParameterConverter}
+	case "datetime":
+		return driver.NotNull{Converter: driver.DefaultParameterConverter}
+	case "nulldatetime":
+		return driver.Null{Converter: driver.DefaultParameterConverter}
+	case "any":
+		return anyTypeConverter{}
+	}
+	panic("invalid fakedb column type of " + typ)
+}
+
+func colTypeToReflectType(typ string) reflect.Type {
+	switch typ {
+	case "bool":
+		return reflect.TypeOf(false)
+	case "nullbool":
+		return reflect.TypeOf(NullBool{})
+	case "int16":
+		return reflect.TypeOf(int16(0))
+	case "nullint16":
+		return reflect.TypeOf(NullInt16{})
+	case "int32":
+		return reflect.TypeOf(int32(0))
+	case "nullint32":
+		return reflect.TypeOf(NullInt32{})
+	case "string":
+		return reflect.TypeOf("")
+	case "nullstring":
+		return reflect.TypeOf(NullString{})
+	case "int64":
+		return reflect.TypeOf(int64(0))
+	case "nullint64":
+		return reflect.TypeOf(NullInt64{})
+	case "float64":
+		return reflect.TypeOf(float64(0))
+	case "nullfloat64":
+		return reflect.TypeOf(NullFloat64{})
+	case "datetime":
+		return reflect.TypeOf(time.Time{})
+	case "any":
+		return reflect.TypeOf(new(any)).Elem()
+	}
+	panic("invalid fakedb column type of " + typ)
+}