Source file src/database/sql/fakedb_test.go

Documentation: database/sql

     1  // Copyright 2011 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package sql
     6  
     7  import (
     8  	"context"
     9  	"database/sql/driver"
    10  	"errors"
    11  	"fmt"
    12  	"io"
    13  	"reflect"
    14  	"slices"
    15  	"strconv"
    16  	"strings"
    17  	"sync"
    18  	"sync/atomic"
    19  	"testing"
    20  	"time"
    21  )
    22  
    23  // fakeDriver is a fake database that implements Go's driver.Driver
    24  // interface, just for testing.
    25  //
    26  // It speaks a query language that's semantically similar to but
    27  // syntactically different and simpler than SQL.  The syntax is as
    28  // follows:
    29  //
    30  //	WIPE
    31  //	CREATE|<tablename>|<col>=<type>,<col>=<type>,...
    32  //	  where types are: "string", [u]int{8,16,32,64}, "bool"
    33  //	INSERT|<tablename>|col=val,col2=val2,col3=?
    34  //	SELECT|<tablename>|projectcol1,projectcol2|filtercol=?,filtercol2=?
    35  //	SELECT|<tablename>|projectcol1,projectcol2|filtercol=?param1,filtercol2=?param2
    36  //
    37  // Any of these can be preceded by PANIC|<method>|, to cause the
    38  // named method on fakeStmt to panic.
    39  //
    40  // Any of these can be proceeded by WAIT|<duration>|, to cause the
    41  // named method on fakeStmt to sleep for the specified duration.
    42  //
    43  // Multiple of these can be combined when separated with a semicolon.
    44  //
    45  // When opening a fakeDriver's database, it starts empty with no
    46  // tables. All tables and data are stored in memory only.
    47  type fakeDriver struct {
    48  	mu         sync.Mutex // guards 3 following fields
    49  	openCount  int        // conn opens
    50  	closeCount int        // conn closes
    51  	waitCh     chan struct{}
    52  	waitingCh  chan struct{}
    53  	dbs        map[string]*fakeDB
    54  }
    55  
    56  type fakeConnector struct {
    57  	name string
    58  
    59  	waiter func(context.Context)
    60  	closed bool
    61  }
    62  
    63  func (c *fakeConnector) Connect(context.Context) (driver.Conn, error) {
    64  	conn, err := fdriver.Open(c.name)
    65  	conn.(*fakeConn).waiter = c.waiter
    66  	return conn, err
    67  }
    68  
    69  func (c *fakeConnector) Driver() driver.Driver {
    70  	return fdriver
    71  }
    72  
    73  func (c *fakeConnector) Close() error {
    74  	if c.closed {
    75  		return errors.New("fakedb: connector is closed")
    76  	}
    77  	c.closed = true
    78  	return nil
    79  }
    80  
    81  type fakeDriverCtx struct {
    82  	fakeDriver
    83  }
    84  
    85  var _ driver.DriverContext = &fakeDriverCtx{}
    86  
    87  func (cc *fakeDriverCtx) OpenConnector(name string) (driver.Connector, error) {
    88  	return &fakeConnector{name: name}, nil
    89  }
    90  
    91  type fakeDB struct {
    92  	name string
    93  
    94  	useRawBytes atomic.Bool
    95  
    96  	mu       sync.Mutex
    97  	tables   map[string]*table
    98  	badConn  bool
    99  	allowAny bool
   100  }
   101  
   102  type fakeError struct {
   103  	Message string
   104  	Wrapped error
   105  }
   106  
   107  func (err fakeError) Error() string {
   108  	return err.Message
   109  }
   110  
   111  func (err fakeError) Unwrap() error {
   112  	return err.Wrapped
   113  }
   114  
   115  type table struct {
   116  	mu      sync.Mutex
   117  	colname []string
   118  	coltype []string
   119  	rows    []*row
   120  }
   121  
   122  func (t *table) columnIndex(name string) int {
   123  	return slices.Index(t.colname, name)
   124  }
   125  
   126  type row struct {
   127  	cols []any // must be same size as its table colname + coltype
   128  }
   129  
   130  type memToucher interface {
   131  	// touchMem reads & writes some memory, to help find data races.
   132  	touchMem()
   133  }
   134  
   135  type fakeConn struct {
   136  	db *fakeDB // where to return ourselves to
   137  
   138  	currTx *fakeTx
   139  
   140  	// Every operation writes to line to enable the race detector
   141  	// check for data races.
   142  	line int64
   143  
   144  	// Stats for tests:
   145  	mu          sync.Mutex
   146  	stmtsMade   int
   147  	stmtsClosed int
   148  	numPrepare  int
   149  
   150  	// bad connection tests; see isBad()
   151  	bad       bool
   152  	stickyBad bool
   153  
   154  	skipDirtySession bool // tests that use Conn should set this to true.
   155  
   156  	// dirtySession tests ResetSession, true if a query has executed
   157  	// until ResetSession is called.
   158  	dirtySession bool
   159  
   160  	// The waiter is called before each query. May be used in place of the "WAIT"
   161  	// directive.
   162  	waiter func(context.Context)
   163  }
   164  
   165  func (c *fakeConn) touchMem() {
   166  	c.line++
   167  }
   168  
   169  func (c *fakeConn) incrStat(v *int) {
   170  	c.mu.Lock()
   171  	*v++
   172  	c.mu.Unlock()
   173  }
   174  
   175  type fakeTx struct {
   176  	c *fakeConn
   177  }
   178  
   179  type boundCol struct {
   180  	Column      string
   181  	Placeholder string
   182  	Ordinal     int
   183  }
   184  
   185  type fakeStmt struct {
   186  	memToucher
   187  	c *fakeConn
   188  	q string // just for debugging
   189  
   190  	cmd   string
   191  	table string
   192  	panic string
   193  	wait  time.Duration
   194  
   195  	next *fakeStmt // used for returning multiple results.
   196  
   197  	closed bool
   198  
   199  	colName      []string // used by CREATE, INSERT, SELECT (selected columns)
   200  	colType      []string // used by CREATE
   201  	colValue     []any    // used by INSERT (mix of strings and "?" for bound params)
   202  	placeholders int      // used by INSERT/SELECT: number of ? params
   203  
   204  	whereCol []boundCol // used by SELECT (all placeholders)
   205  
   206  	placeholderConverter []driver.ValueConverter // used by INSERT
   207  }
   208  
   209  var fdriver driver.Driver = &fakeDriver{}
   210  
   211  func init() {
   212  	Register("test", fdriver)
   213  }
   214  
   215  type Dummy struct {
   216  	driver.Driver
   217  }
   218  
   219  func TestDrivers(t *testing.T) {
   220  	unregisterAllDrivers()
   221  	Register("test", fdriver)
   222  	Register("invalid", Dummy{})
   223  	all := Drivers()
   224  	if len(all) < 2 || !slices.IsSorted(all) || !slices.Contains(all, "test") || !slices.Contains(all, "invalid") {
   225  		t.Fatalf("Drivers = %v, want sorted list with at least [invalid, test]", all)
   226  	}
   227  }
   228  
   229  // hook to simulate connection failures
   230  var hookOpenErr struct {
   231  	sync.Mutex
   232  	fn func() error
   233  }
   234  
   235  func setHookOpenErr(fn func() error) {
   236  	hookOpenErr.Lock()
   237  	defer hookOpenErr.Unlock()
   238  	hookOpenErr.fn = fn
   239  }
   240  
   241  // Supports dsn forms:
   242  //
   243  //	<dbname>
   244  //	<dbname>;<opts>  (only currently supported option is `badConn`,
   245  //	                  which causes driver.ErrBadConn to be returned on
   246  //	                  every other conn.Begin())
   247  func (d *fakeDriver) Open(dsn string) (driver.Conn, error) {
   248  	hookOpenErr.Lock()
   249  	fn := hookOpenErr.fn
   250  	hookOpenErr.Unlock()
   251  	if fn != nil {
   252  		if err := fn(); err != nil {
   253  			return nil, err
   254  		}
   255  	}
   256  	parts := strings.Split(dsn, ";")
   257  	if len(parts) < 1 {
   258  		return nil, errors.New("fakedb: no database name")
   259  	}
   260  	name := parts[0]
   261  
   262  	db := d.getDB(name)
   263  
   264  	d.mu.Lock()
   265  	d.openCount++
   266  	d.mu.Unlock()
   267  	conn := &fakeConn{db: db}
   268  
   269  	if len(parts) >= 2 && parts[1] == "badConn" {
   270  		conn.bad = true
   271  	}
   272  	if d.waitCh != nil {
   273  		d.waitingCh <- struct{}{}
   274  		<-d.waitCh
   275  		d.waitCh = nil
   276  		d.waitingCh = nil
   277  	}
   278  	return conn, nil
   279  }
   280  
   281  func (d *fakeDriver) getDB(name string) *fakeDB {
   282  	d.mu.Lock()
   283  	defer d.mu.Unlock()
   284  	if d.dbs == nil {
   285  		d.dbs = make(map[string]*fakeDB)
   286  	}
   287  	db, ok := d.dbs[name]
   288  	if !ok {
   289  		db = &fakeDB{name: name}
   290  		d.dbs[name] = db
   291  	}
   292  	return db
   293  }
   294  
   295  func (db *fakeDB) wipe() {
   296  	db.mu.Lock()
   297  	defer db.mu.Unlock()
   298  	db.tables = nil
   299  }
   300  
   301  func (db *fakeDB) createTable(name string, columnNames, columnTypes []string) error {
   302  	db.mu.Lock()
   303  	defer db.mu.Unlock()
   304  	if db.tables == nil {
   305  		db.tables = make(map[string]*table)
   306  	}
   307  	if _, exist := db.tables[name]; exist {
   308  		return fmt.Errorf("fakedb: table %q already exists", name)
   309  	}
   310  	if len(columnNames) != len(columnTypes) {
   311  		return fmt.Errorf("fakedb: create table of %q len(names) != len(types): %d vs %d",
   312  			name, len(columnNames), len(columnTypes))
   313  	}
   314  	db.tables[name] = &table{colname: columnNames, coltype: columnTypes}
   315  	return nil
   316  }
   317  
   318  // must be called with db.mu lock held
   319  func (db *fakeDB) table(table string) (*table, bool) {
   320  	if db.tables == nil {
   321  		return nil, false
   322  	}
   323  	t, ok := db.tables[table]
   324  	return t, ok
   325  }
   326  
   327  func (db *fakeDB) columnType(table, column string) (typ string, ok bool) {
   328  	db.mu.Lock()
   329  	defer db.mu.Unlock()
   330  	t, ok := db.table(table)
   331  	if !ok {
   332  		return
   333  	}
   334  	if i := slices.Index(t.colname, column); i != -1 {
   335  		return t.coltype[i], true
   336  	}
   337  	return "", false
   338  }
   339  
   340  func (c *fakeConn) isBad() bool {
   341  	if c.stickyBad {
   342  		return true
   343  	} else if c.bad {
   344  		if c.db == nil {
   345  			return false
   346  		}
   347  		// alternate between bad conn and not bad conn
   348  		c.db.badConn = !c.db.badConn
   349  		return c.db.badConn
   350  	} else {
   351  		return false
   352  	}
   353  }
   354  
   355  func (c *fakeConn) isDirtyAndMark() bool {
   356  	if c.skipDirtySession {
   357  		return false
   358  	}
   359  	if c.currTx != nil {
   360  		c.dirtySession = true
   361  		return false
   362  	}
   363  	if c.dirtySession {
   364  		return true
   365  	}
   366  	c.dirtySession = true
   367  	return false
   368  }
   369  
   370  func (c *fakeConn) Begin() (driver.Tx, error) {
   371  	if c.isBad() {
   372  		return nil, fakeError{Wrapped: driver.ErrBadConn}
   373  	}
   374  	if c.currTx != nil {
   375  		return nil, errors.New("fakedb: already in a transaction")
   376  	}
   377  	c.touchMem()
   378  	c.currTx = &fakeTx{c: c}
   379  	return c.currTx, nil
   380  }
   381  
   382  var hookPostCloseConn struct {
   383  	sync.Mutex
   384  	fn func(*fakeConn, error)
   385  }
   386  
   387  func setHookpostCloseConn(fn func(*fakeConn, error)) {
   388  	hookPostCloseConn.Lock()
   389  	defer hookPostCloseConn.Unlock()
   390  	hookPostCloseConn.fn = fn
   391  }
   392  
   393  var testStrictClose *testing.T
   394  
   395  // setStrictFakeConnClose sets the t to Errorf on when fakeConn.Close
   396  // fails to close. If nil, the check is disabled.
   397  func setStrictFakeConnClose(t *testing.T) {
   398  	testStrictClose = t
   399  }
   400  
   401  func (c *fakeConn) ResetSession(ctx context.Context) error {
   402  	c.dirtySession = false
   403  	c.currTx = nil
   404  	if c.isBad() {
   405  		return fakeError{Message: "Reset Session: bad conn", Wrapped: driver.ErrBadConn}
   406  	}
   407  	return nil
   408  }
   409  
   410  var _ driver.Validator = (*fakeConn)(nil)
   411  
   412  func (c *fakeConn) IsValid() bool {
   413  	return !c.isBad()
   414  }
   415  
   416  func (c *fakeConn) Close() (err error) {
   417  	drv := fdriver.(*fakeDriver)
   418  	defer func() {
   419  		if err != nil && testStrictClose != nil {
   420  			testStrictClose.Errorf("failed to close a test fakeConn: %v", err)
   421  		}
   422  		hookPostCloseConn.Lock()
   423  		fn := hookPostCloseConn.fn
   424  		hookPostCloseConn.Unlock()
   425  		if fn != nil {
   426  			fn(c, err)
   427  		}
   428  		if err == nil {
   429  			drv.mu.Lock()
   430  			drv.closeCount++
   431  			drv.mu.Unlock()
   432  		}
   433  	}()
   434  	c.touchMem()
   435  	if c.currTx != nil {
   436  		return errors.New("fakedb: can't close fakeConn; in a Transaction")
   437  	}
   438  	if c.db == nil {
   439  		return errors.New("fakedb: can't close fakeConn; already closed")
   440  	}
   441  	if c.stmtsMade > c.stmtsClosed {
   442  		return errors.New("fakedb: can't close; dangling statement(s)")
   443  	}
   444  	c.db = nil
   445  	return nil
   446  }
   447  
   448  func checkSubsetTypes(allowAny bool, args []driver.NamedValue) error {
   449  	for _, arg := range args {
   450  		switch arg.Value.(type) {
   451  		case int64, float64, bool, nil, []byte, string, time.Time:
   452  		default:
   453  			if !allowAny {
   454  				return fmt.Errorf("fakedb: invalid argument ordinal %[1]d: %[2]v, type %[2]T", arg.Ordinal, arg.Value)
   455  			}
   456  		}
   457  	}
   458  	return nil
   459  }
   460  
   461  func (c *fakeConn) Exec(query string, args []driver.Value) (driver.Result, error) {
   462  	// Ensure that ExecContext is called if available.
   463  	panic("ExecContext was not called.")
   464  }
   465  
   466  func (c *fakeConn) ExecContext(ctx context.Context, query string, args []driver.NamedValue) (driver.Result, error) {
   467  	// This is an optional interface, but it's implemented here
   468  	// just to check that all the args are of the proper types.
   469  	// ErrSkip is returned so the caller acts as if we didn't
   470  	// implement this at all.
   471  	err := checkSubsetTypes(c.db.allowAny, args)
   472  	if err != nil {
   473  		return nil, err
   474  	}
   475  	return nil, driver.ErrSkip
   476  }
   477  
   478  func (c *fakeConn) Query(query string, args []driver.Value) (driver.Rows, error) {
   479  	// Ensure that ExecContext is called if available.
   480  	panic("QueryContext was not called.")
   481  }
   482  
   483  func (c *fakeConn) QueryContext(ctx context.Context, query string, args []driver.NamedValue) (driver.Rows, error) {
   484  	// This is an optional interface, but it's implemented here
   485  	// just to check that all the args are of the proper types.
   486  	// ErrSkip is returned so the caller acts as if we didn't
   487  	// implement this at all.
   488  	err := checkSubsetTypes(c.db.allowAny, args)
   489  	if err != nil {
   490  		return nil, err
   491  	}
   492  	return nil, driver.ErrSkip
   493  }
   494  
   495  func errf(msg string, args ...any) error {
   496  	return errors.New("fakedb: " + fmt.Sprintf(msg, args...))
   497  }
   498  
   499  // parts are table|selectCol1,selectCol2|whereCol=?,whereCol2=?
   500  // (note that where columns must always contain ? marks,
   501  // just a limitation for fakedb)
   502  func (c *fakeConn) prepareSelect(stmt *fakeStmt, parts []string) (*fakeStmt, error) {
   503  	if len(parts) != 3 {
   504  		stmt.Close()
   505  		return nil, errf("invalid SELECT syntax with %d parts; want 3", len(parts))
   506  	}
   507  	stmt.table = parts[0]
   508  
   509  	stmt.colName = strings.Split(parts[1], ",")
   510  	for n, colspec := range strings.Split(parts[2], ",") {
   511  		if colspec == "" {
   512  			continue
   513  		}
   514  		nameVal := strings.Split(colspec, "=")
   515  		if len(nameVal) != 2 {
   516  			stmt.Close()
   517  			return nil, errf("SELECT on table %q has invalid column spec of %q (index %d)", stmt.table, colspec, n)
   518  		}
   519  		column, value := nameVal[0], nameVal[1]
   520  		_, ok := c.db.columnType(stmt.table, column)
   521  		if !ok {
   522  			stmt.Close()
   523  			return nil, errf("SELECT on table %q references non-existent column %q", stmt.table, column)
   524  		}
   525  		if !strings.HasPrefix(value, "?") {
   526  			stmt.Close()
   527  			return nil, errf("SELECT on table %q has pre-bound value for where column %q; need a question mark",
   528  				stmt.table, column)
   529  		}
   530  		stmt.placeholders++
   531  		stmt.whereCol = append(stmt.whereCol, boundCol{Column: column, Placeholder: value, Ordinal: stmt.placeholders})
   532  	}
   533  	return stmt, nil
   534  }
   535  
   536  // parts are table|col=type,col2=type2
   537  func (c *fakeConn) prepareCreate(stmt *fakeStmt, parts []string) (*fakeStmt, error) {
   538  	if len(parts) != 2 {
   539  		stmt.Close()
   540  		return nil, errf("invalid CREATE syntax with %d parts; want 2", len(parts))
   541  	}
   542  	stmt.table = parts[0]
   543  	for n, colspec := range strings.Split(parts[1], ",") {
   544  		nameType := strings.Split(colspec, "=")
   545  		if len(nameType) != 2 {
   546  			stmt.Close()
   547  			return nil, errf("CREATE table %q has invalid column spec of %q (index %d)", stmt.table, colspec, n)
   548  		}
   549  		stmt.colName = append(stmt.colName, nameType[0])
   550  		stmt.colType = append(stmt.colType, nameType[1])
   551  	}
   552  	return stmt, nil
   553  }
   554  
   555  // parts are table|col=?,col2=val
   556  func (c *fakeConn) prepareInsert(ctx context.Context, stmt *fakeStmt, parts []string) (*fakeStmt, error) {
   557  	if len(parts) != 2 {
   558  		stmt.Close()
   559  		return nil, errf("invalid INSERT syntax with %d parts; want 2", len(parts))
   560  	}
   561  	stmt.table = parts[0]
   562  	for n, colspec := range strings.Split(parts[1], ",") {
   563  		nameVal := strings.Split(colspec, "=")
   564  		if len(nameVal) != 2 {
   565  			stmt.Close()
   566  			return nil, errf("INSERT table %q has invalid column spec of %q (index %d)", stmt.table, colspec, n)
   567  		}
   568  		column, value := nameVal[0], nameVal[1]
   569  		ctype, ok := c.db.columnType(stmt.table, column)
   570  		if !ok {
   571  			stmt.Close()
   572  			return nil, errf("INSERT table %q references non-existent column %q", stmt.table, column)
   573  		}
   574  		stmt.colName = append(stmt.colName, column)
   575  
   576  		if !strings.HasPrefix(value, "?") {
   577  			var subsetVal any
   578  			// Convert to driver subset type
   579  			switch ctype {
   580  			case "string":
   581  				subsetVal = []byte(value)
   582  			case "blob":
   583  				subsetVal = []byte(value)
   584  			case "int32":
   585  				i, err := strconv.Atoi(value)
   586  				if err != nil {
   587  					stmt.Close()
   588  					return nil, errf("invalid conversion to int32 from %q", value)
   589  				}
   590  				subsetVal = int64(i) // int64 is a subset type, but not int32
   591  			case "table": // For testing cursor reads.
   592  				c.skipDirtySession = true
   593  				vparts := strings.Split(value, "!")
   594  
   595  				substmt, err := c.PrepareContext(ctx, fmt.Sprintf("SELECT|%s|%s|", vparts[0], strings.Join(vparts[1:], ",")))
   596  				if err != nil {
   597  					return nil, err
   598  				}
   599  				cursor, err := (substmt.(driver.StmtQueryContext)).QueryContext(ctx, []driver.NamedValue{})
   600  				substmt.Close()
   601  				if err != nil {
   602  					return nil, err
   603  				}
   604  				subsetVal = cursor
   605  			default:
   606  				stmt.Close()
   607  				return nil, errf("unsupported conversion for pre-bound parameter %q to type %q", value, ctype)
   608  			}
   609  			stmt.colValue = append(stmt.colValue, subsetVal)
   610  		} else {
   611  			stmt.placeholders++
   612  			stmt.placeholderConverter = append(stmt.placeholderConverter, converterForType(ctype))
   613  			stmt.colValue = append(stmt.colValue, value)
   614  		}
   615  	}
   616  	return stmt, nil
   617  }
   618  
   619  // hook to simulate broken connections
   620  var hookPrepareBadConn func() bool
   621  
   622  func (c *fakeConn) Prepare(query string) (driver.Stmt, error) {
   623  	panic("use PrepareContext")
   624  }
   625  
   626  func (c *fakeConn) PrepareContext(ctx context.Context, query string) (driver.Stmt, error) {
   627  	c.numPrepare++
   628  	if c.db == nil {
   629  		panic("nil c.db; conn = " + fmt.Sprintf("%#v", c))
   630  	}
   631  
   632  	if c.stickyBad || (hookPrepareBadConn != nil && hookPrepareBadConn()) {
   633  		return nil, fakeError{Message: "Prepare: Sticky Bad", Wrapped: driver.ErrBadConn}
   634  	}
   635  
   636  	c.touchMem()
   637  	var firstStmt, prev *fakeStmt
   638  	for _, query := range strings.Split(query, ";") {
   639  		parts := strings.Split(query, "|")
   640  		if len(parts) < 1 {
   641  			return nil, errf("empty query")
   642  		}
   643  		stmt := &fakeStmt{q: query, c: c, memToucher: c}
   644  		if firstStmt == nil {
   645  			firstStmt = stmt
   646  		}
   647  		if len(parts) >= 3 {
   648  			switch parts[0] {
   649  			case "PANIC":
   650  				stmt.panic = parts[1]
   651  				parts = parts[2:]
   652  			case "WAIT":
   653  				wait, err := time.ParseDuration(parts[1])
   654  				if err != nil {
   655  					return nil, errf("expected section after WAIT to be a duration, got %q %v", parts[1], err)
   656  				}
   657  				parts = parts[2:]
   658  				stmt.wait = wait
   659  			}
   660  		}
   661  		cmd := parts[0]
   662  		stmt.cmd = cmd
   663  		parts = parts[1:]
   664  
   665  		if c.waiter != nil {
   666  			c.waiter(ctx)
   667  			if err := ctx.Err(); err != nil {
   668  				return nil, err
   669  			}
   670  		}
   671  
   672  		if stmt.wait > 0 {
   673  			wait := time.NewTimer(stmt.wait)
   674  			select {
   675  			case <-wait.C:
   676  			case <-ctx.Done():
   677  				wait.Stop()
   678  				return nil, ctx.Err()
   679  			}
   680  		}
   681  
   682  		c.incrStat(&c.stmtsMade)
   683  		var err error
   684  		switch cmd {
   685  		case "WIPE":
   686  			// Nothing
   687  		case "USE_RAWBYTES":
   688  			c.db.useRawBytes.Store(true)
   689  		case "SELECT":
   690  			stmt, err = c.prepareSelect(stmt, parts)
   691  		case "CREATE":
   692  			stmt, err = c.prepareCreate(stmt, parts)
   693  		case "INSERT":
   694  			stmt, err = c.prepareInsert(ctx, stmt, parts)
   695  		case "NOSERT":
   696  			// Do all the prep-work like for an INSERT but don't actually insert the row.
   697  			// Used for some of the concurrent tests.
   698  			stmt, err = c.prepareInsert(ctx, stmt, parts)
   699  		default:
   700  			stmt.Close()
   701  			return nil, errf("unsupported command type %q", cmd)
   702  		}
   703  		if err != nil {
   704  			return nil, err
   705  		}
   706  		if prev != nil {
   707  			prev.next = stmt
   708  		}
   709  		prev = stmt
   710  	}
   711  	return firstStmt, nil
   712  }
   713  
   714  func (s *fakeStmt) ColumnConverter(idx int) driver.ValueConverter {
   715  	if s.panic == "ColumnConverter" {
   716  		panic(s.panic)
   717  	}
   718  	if len(s.placeholderConverter) == 0 {
   719  		return driver.DefaultParameterConverter
   720  	}
   721  	return s.placeholderConverter[idx]
   722  }
   723  
   724  func (s *fakeStmt) Close() error {
   725  	if s.panic == "Close" {
   726  		panic(s.panic)
   727  	}
   728  	if s.c == nil {
   729  		panic("nil conn in fakeStmt.Close")
   730  	}
   731  	if s.c.db == nil {
   732  		panic("in fakeStmt.Close, conn's db is nil (already closed)")
   733  	}
   734  	s.touchMem()
   735  	if !s.closed {
   736  		s.c.incrStat(&s.c.stmtsClosed)
   737  		s.closed = true
   738  	}
   739  	if s.next != nil {
   740  		s.next.Close()
   741  	}
   742  	return nil
   743  }
   744  
   745  var errClosed = errors.New("fakedb: statement has been closed")
   746  
   747  // hook to simulate broken connections
   748  var hookExecBadConn func() bool
   749  
   750  func (s *fakeStmt) Exec(args []driver.Value) (driver.Result, error) {
   751  	panic("Using ExecContext")
   752  }
   753  
   754  var errFakeConnSessionDirty = errors.New("fakedb: session is dirty")
   755  
   756  func (s *fakeStmt) ExecContext(ctx context.Context, args []driver.NamedValue) (driver.Result, error) {
   757  	if s.panic == "Exec" {
   758  		panic(s.panic)
   759  	}
   760  	if s.closed {
   761  		return nil, errClosed
   762  	}
   763  
   764  	if s.c.stickyBad || (hookExecBadConn != nil && hookExecBadConn()) {
   765  		return nil, fakeError{Message: "Exec: Sticky Bad", Wrapped: driver.ErrBadConn}
   766  	}
   767  	if s.c.isDirtyAndMark() {
   768  		return nil, errFakeConnSessionDirty
   769  	}
   770  
   771  	err := checkSubsetTypes(s.c.db.allowAny, args)
   772  	if err != nil {
   773  		return nil, err
   774  	}
   775  	s.touchMem()
   776  
   777  	if s.wait > 0 {
   778  		time.Sleep(s.wait)
   779  	}
   780  
   781  	select {
   782  	default:
   783  	case <-ctx.Done():
   784  		return nil, ctx.Err()
   785  	}
   786  
   787  	db := s.c.db
   788  	switch s.cmd {
   789  	case "WIPE":
   790  		db.wipe()
   791  		return driver.ResultNoRows, nil
   792  	case "USE_RAWBYTES":
   793  		s.c.db.useRawBytes.Store(true)
   794  		return driver.ResultNoRows, nil
   795  	case "CREATE":
   796  		if err := db.createTable(s.table, s.colName, s.colType); err != nil {
   797  			return nil, err
   798  		}
   799  		return driver.ResultNoRows, nil
   800  	case "INSERT":
   801  		return s.execInsert(args, true)
   802  	case "NOSERT":
   803  		// Do all the prep-work like for an INSERT but don't actually insert the row.
   804  		// Used for some of the concurrent tests.
   805  		return s.execInsert(args, false)
   806  	}
   807  	return nil, fmt.Errorf("fakedb: unimplemented statement Exec command type of %q", s.cmd)
   808  }
   809  
   810  func valueFromPlaceholderName(args []driver.NamedValue, name string) driver.Value {
   811  	for i := range args {
   812  		if args[i].Name == name {
   813  			return args[i].Value
   814  		}
   815  	}
   816  	return nil
   817  }
   818  
   819  // When doInsert is true, add the row to the table.
   820  // When doInsert is false do prep-work and error checking, but don't
   821  // actually add the row to the table.
   822  func (s *fakeStmt) execInsert(args []driver.NamedValue, doInsert bool) (driver.Result, error) {
   823  	db := s.c.db
   824  	if len(args) != s.placeholders {
   825  		panic("error in pkg db; should only get here if size is correct")
   826  	}
   827  	db.mu.Lock()
   828  	t, ok := db.table(s.table)
   829  	db.mu.Unlock()
   830  	if !ok {
   831  		return nil, fmt.Errorf("fakedb: table %q doesn't exist", s.table)
   832  	}
   833  
   834  	t.mu.Lock()
   835  	defer t.mu.Unlock()
   836  
   837  	var cols []any
   838  	if doInsert {
   839  		cols = make([]any, len(t.colname))
   840  	}
   841  	argPos := 0
   842  	for n, colname := range s.colName {
   843  		colidx := t.columnIndex(colname)
   844  		if colidx == -1 {
   845  			return nil, fmt.Errorf("fakedb: column %q doesn't exist or dropped since prepared statement was created", colname)
   846  		}
   847  		var val any
   848  		if strvalue, ok := s.colValue[n].(string); ok && strings.HasPrefix(strvalue, "?") {
   849  			if strvalue == "?" {
   850  				val = args[argPos].Value
   851  			} else {
   852  				// Assign value from argument placeholder name.
   853  				if v := valueFromPlaceholderName(args, strvalue[1:]); v != nil {
   854  					val = v
   855  				}
   856  			}
   857  			argPos++
   858  		} else {
   859  			val = s.colValue[n]
   860  		}
   861  		if doInsert {
   862  			cols[colidx] = val
   863  		}
   864  	}
   865  
   866  	if doInsert {
   867  		t.rows = append(t.rows, &row{cols: cols})
   868  	}
   869  	return driver.RowsAffected(1), nil
   870  }
   871  
   872  // hook to simulate broken connections
   873  var hookQueryBadConn func() bool
   874  
   875  func (s *fakeStmt) Query(args []driver.Value) (driver.Rows, error) {
   876  	panic("Use QueryContext")
   877  }
   878  
   879  func (s *fakeStmt) QueryContext(ctx context.Context, args []driver.NamedValue) (driver.Rows, error) {
   880  	if s.panic == "Query" {
   881  		panic(s.panic)
   882  	}
   883  	if s.closed {
   884  		return nil, errClosed
   885  	}
   886  
   887  	if s.c.stickyBad || (hookQueryBadConn != nil && hookQueryBadConn()) {
   888  		return nil, fakeError{Message: "Query: Sticky Bad", Wrapped: driver.ErrBadConn}
   889  	}
   890  	if s.c.isDirtyAndMark() {
   891  		return nil, errFakeConnSessionDirty
   892  	}
   893  
   894  	err := checkSubsetTypes(s.c.db.allowAny, args)
   895  	if err != nil {
   896  		return nil, err
   897  	}
   898  
   899  	s.touchMem()
   900  	db := s.c.db
   901  	if len(args) != s.placeholders {
   902  		panic("error in pkg db; should only get here if size is correct")
   903  	}
   904  
   905  	setMRows := make([][]*row, 0, 1)
   906  	setColumns := make([][]string, 0, 1)
   907  	setColType := make([][]string, 0, 1)
   908  
   909  	for {
   910  		db.mu.Lock()
   911  		t, ok := db.table(s.table)
   912  		db.mu.Unlock()
   913  		if !ok {
   914  			return nil, fmt.Errorf("fakedb: table %q doesn't exist", s.table)
   915  		}
   916  
   917  		if s.table == "magicquery" {
   918  			if len(s.whereCol) == 2 && s.whereCol[0].Column == "op" && s.whereCol[1].Column == "millis" {
   919  				if args[0].Value == "sleep" {
   920  					time.Sleep(time.Duration(args[1].Value.(int64)) * time.Millisecond)
   921  				}
   922  			}
   923  		}
   924  		if s.table == "tx_status" && s.colName[0] == "tx_status" {
   925  			txStatus := "autocommit"
   926  			if s.c.currTx != nil {
   927  				txStatus = "transaction"
   928  			}
   929  			cursor := &rowsCursor{
   930  				db:        s.c.db,
   931  				parentMem: s.c,
   932  				posRow:    -1,
   933  				rows: [][]*row{
   934  					{
   935  						{
   936  							cols: []any{
   937  								txStatus,
   938  							},
   939  						},
   940  					},
   941  				},
   942  				cols: [][]string{
   943  					{
   944  						"tx_status",
   945  					},
   946  				},
   947  				colType: [][]string{
   948  					{
   949  						"string",
   950  					},
   951  				},
   952  				errPos: -1,
   953  			}
   954  			return cursor, nil
   955  		}
   956  
   957  		t.mu.Lock()
   958  
   959  		colIdx := make(map[string]int) // select column name -> column index in table
   960  		for _, name := range s.colName {
   961  			idx := t.columnIndex(name)
   962  			if idx == -1 {
   963  				t.mu.Unlock()
   964  				return nil, fmt.Errorf("fakedb: unknown column name %q", name)
   965  			}
   966  			colIdx[name] = idx
   967  		}
   968  
   969  		mrows := []*row{}
   970  	rows:
   971  		for _, trow := range t.rows {
   972  			// Process the where clause, skipping non-match rows. This is lazy
   973  			// and just uses fmt.Sprintf("%v") to test equality. Good enough
   974  			// for test code.
   975  			for _, wcol := range s.whereCol {
   976  				idx := t.columnIndex(wcol.Column)
   977  				if idx == -1 {
   978  					t.mu.Unlock()
   979  					return nil, fmt.Errorf("fakedb: invalid where clause column %q", wcol)
   980  				}
   981  				tcol := trow.cols[idx]
   982  				if bs, ok := tcol.([]byte); ok {
   983  					// lazy hack to avoid sprintf %v on a []byte
   984  					tcol = string(bs)
   985  				}
   986  				var argValue any
   987  				if wcol.Placeholder == "?" {
   988  					argValue = args[wcol.Ordinal-1].Value
   989  				} else {
   990  					if v := valueFromPlaceholderName(args, wcol.Placeholder[1:]); v != nil {
   991  						argValue = v
   992  					}
   993  				}
   994  				if fmt.Sprintf("%v", tcol) != fmt.Sprintf("%v", argValue) {
   995  					continue rows
   996  				}
   997  			}
   998  			mrow := &row{cols: make([]any, len(s.colName))}
   999  			for seli, name := range s.colName {
  1000  				mrow.cols[seli] = trow.cols[colIdx[name]]
  1001  			}
  1002  			mrows = append(mrows, mrow)
  1003  		}
  1004  
  1005  		var colType []string
  1006  		for _, column := range s.colName {
  1007  			colType = append(colType, t.coltype[t.columnIndex(column)])
  1008  		}
  1009  
  1010  		t.mu.Unlock()
  1011  
  1012  		setMRows = append(setMRows, mrows)
  1013  		setColumns = append(setColumns, s.colName)
  1014  		setColType = append(setColType, colType)
  1015  
  1016  		if s.next == nil {
  1017  			break
  1018  		}
  1019  		s = s.next
  1020  	}
  1021  
  1022  	cursor := &rowsCursor{
  1023  		db:        s.c.db,
  1024  		parentMem: s.c,
  1025  		posRow:    -1,
  1026  		rows:      setMRows,
  1027  		cols:      setColumns,
  1028  		colType:   setColType,
  1029  		errPos:    -1,
  1030  	}
  1031  	return cursor, nil
  1032  }
  1033  
  1034  func (s *fakeStmt) NumInput() int {
  1035  	if s.panic == "NumInput" {
  1036  		panic(s.panic)
  1037  	}
  1038  	return s.placeholders
  1039  }
  1040  
  1041  // hook to simulate broken connections
  1042  var hookCommitBadConn func() bool
  1043  
  1044  func (tx *fakeTx) Commit() error {
  1045  	tx.c.currTx = nil
  1046  	if hookCommitBadConn != nil && hookCommitBadConn() {
  1047  		return fakeError{Message: "Commit: Hook Bad Conn", Wrapped: driver.ErrBadConn}
  1048  	}
  1049  	tx.c.touchMem()
  1050  	return nil
  1051  }
  1052  
  1053  // hook to simulate broken connections
  1054  var hookRollbackBadConn func() bool
  1055  
  1056  func (tx *fakeTx) Rollback() error {
  1057  	tx.c.currTx = nil
  1058  	if hookRollbackBadConn != nil && hookRollbackBadConn() {
  1059  		return fakeError{Message: "Rollback: Hook Bad Conn", Wrapped: driver.ErrBadConn}
  1060  	}
  1061  	tx.c.touchMem()
  1062  	return nil
  1063  }
  1064  
  1065  type rowsCursor struct {
  1066  	db        *fakeDB
  1067  	parentMem memToucher
  1068  	cols      [][]string
  1069  	colType   [][]string
  1070  	posSet    int
  1071  	posRow    int
  1072  	rows      [][]*row
  1073  	closed    bool
  1074  
  1075  	// errPos and err are for making Next return early with error.
  1076  	errPos int
  1077  	err    error
  1078  
  1079  	// a clone of slices to give out to clients, indexed by the
  1080  	// original slice's first byte address.  we clone them
  1081  	// just so we're able to corrupt them on close.
  1082  	bytesClone map[*byte][]byte
  1083  
  1084  	// Every operation writes to line to enable the race detector
  1085  	// check for data races.
  1086  	// This is separate from the fakeConn.line to allow for drivers that
  1087  	// can start multiple queries on the same transaction at the same time.
  1088  	line int64
  1089  
  1090  	// closeErr is returned when rowsCursor.Close
  1091  	closeErr error
  1092  }
  1093  
  1094  func (rc *rowsCursor) touchMem() {
  1095  	rc.parentMem.touchMem()
  1096  	rc.line++
  1097  }
  1098  
  1099  func (rc *rowsCursor) Close() error {
  1100  	rc.touchMem()
  1101  	rc.parentMem.touchMem()
  1102  	rc.closed = true
  1103  	return rc.closeErr
  1104  }
  1105  
  1106  func (rc *rowsCursor) Columns() []string {
  1107  	return rc.cols[rc.posSet]
  1108  }
  1109  
  1110  func (rc *rowsCursor) ColumnTypeScanType(index int) reflect.Type {
  1111  	return colTypeToReflectType(rc.colType[rc.posSet][index])
  1112  }
  1113  
  1114  var rowsCursorNextHook func(dest []driver.Value) error
  1115  
  1116  func (rc *rowsCursor) Next(dest []driver.Value) error {
  1117  	if rowsCursorNextHook != nil {
  1118  		return rowsCursorNextHook(dest)
  1119  	}
  1120  
  1121  	if rc.closed {
  1122  		return errors.New("fakedb: cursor is closed")
  1123  	}
  1124  	rc.touchMem()
  1125  	rc.posRow++
  1126  	if rc.posRow == rc.errPos {
  1127  		return rc.err
  1128  	}
  1129  	if rc.posRow >= len(rc.rows[rc.posSet]) {
  1130  		return io.EOF // per interface spec
  1131  	}
  1132  	for i, v := range rc.rows[rc.posSet][rc.posRow].cols {
  1133  		// TODO(bradfitz): convert to subset types? naah, I
  1134  		// think the subset types should only be input to
  1135  		// driver, but the sql package should be able to handle
  1136  		// a wider range of types coming out of drivers. all
  1137  		// for ease of drivers, and to prevent drivers from
  1138  		// messing up conversions or doing them differently.
  1139  		dest[i] = v
  1140  
  1141  		if bs, ok := v.([]byte); ok && !rc.db.useRawBytes.Load() {
  1142  			if rc.bytesClone == nil {
  1143  				rc.bytesClone = make(map[*byte][]byte)
  1144  			}
  1145  			clone, ok := rc.bytesClone[&bs[0]]
  1146  			if !ok {
  1147  				clone = make([]byte, len(bs))
  1148  				copy(clone, bs)
  1149  				rc.bytesClone[&bs[0]] = clone
  1150  			}
  1151  			dest[i] = clone
  1152  		}
  1153  	}
  1154  	return nil
  1155  }
  1156  
  1157  func (rc *rowsCursor) HasNextResultSet() bool {
  1158  	rc.touchMem()
  1159  	return rc.posSet < len(rc.rows)-1
  1160  }
  1161  
  1162  func (rc *rowsCursor) NextResultSet() error {
  1163  	rc.touchMem()
  1164  	if rc.HasNextResultSet() {
  1165  		rc.posSet++
  1166  		rc.posRow = -1
  1167  		return nil
  1168  	}
  1169  	return io.EOF // Per interface spec.
  1170  }
  1171  
  1172  // fakeDriverString is like driver.String, but indirects pointers like
  1173  // DefaultValueConverter.
  1174  //
  1175  // This could be surprising behavior to retroactively apply to
  1176  // driver.String now that Go1 is out, but this is convenient for
  1177  // our TestPointerParamsAndScans.
  1178  type fakeDriverString struct{}
  1179  
  1180  func (fakeDriverString) ConvertValue(v any) (driver.Value, error) {
  1181  	switch c := v.(type) {
  1182  	case string, []byte:
  1183  		return v, nil
  1184  	case *string:
  1185  		if c == nil {
  1186  			return nil, nil
  1187  		}
  1188  		return *c, nil
  1189  	}
  1190  	return fmt.Sprintf("%v", v), nil
  1191  }
  1192  
  1193  type anyTypeConverter struct{}
  1194  
  1195  func (anyTypeConverter) ConvertValue(v any) (driver.Value, error) {
  1196  	return v, nil
  1197  }
  1198  
  1199  func converterForType(typ string) driver.ValueConverter {
  1200  	switch typ {
  1201  	case "bool":
  1202  		return driver.Bool
  1203  	case "nullbool":
  1204  		return driver.Null{Converter: driver.Bool}
  1205  	case "byte", "int16":
  1206  		return driver.NotNull{Converter: driver.DefaultParameterConverter}
  1207  	case "int32":
  1208  		return driver.Int32
  1209  	case "nullbyte", "nullint32", "nullint16":
  1210  		return driver.Null{Converter: driver.DefaultParameterConverter}
  1211  	case "string":
  1212  		return driver.NotNull{Converter: fakeDriverString{}}
  1213  	case "nullstring":
  1214  		return driver.Null{Converter: fakeDriverString{}}
  1215  	case "int64":
  1216  		// TODO(coopernurse): add type-specific converter
  1217  		return driver.NotNull{Converter: driver.DefaultParameterConverter}
  1218  	case "nullint64":
  1219  		// TODO(coopernurse): add type-specific converter
  1220  		return driver.Null{Converter: driver.DefaultParameterConverter}
  1221  	case "float64":
  1222  		// TODO(coopernurse): add type-specific converter
  1223  		return driver.NotNull{Converter: driver.DefaultParameterConverter}
  1224  	case "nullfloat64":
  1225  		// TODO(coopernurse): add type-specific converter
  1226  		return driver.Null{Converter: driver.DefaultParameterConverter}
  1227  	case "datetime":
  1228  		return driver.NotNull{Converter: driver.DefaultParameterConverter}
  1229  	case "nulldatetime":
  1230  		return driver.Null{Converter: driver.DefaultParameterConverter}
  1231  	case "any":
  1232  		return anyTypeConverter{}
  1233  	}
  1234  	panic("invalid fakedb column type of " + typ)
  1235  }
  1236  
  1237  func colTypeToReflectType(typ string) reflect.Type {
  1238  	switch typ {
  1239  	case "bool":
  1240  		return reflect.TypeFor[bool]()
  1241  	case "nullbool":
  1242  		return reflect.TypeFor[NullBool]()
  1243  	case "int16":
  1244  		return reflect.TypeFor[int16]()
  1245  	case "nullint16":
  1246  		return reflect.TypeFor[NullInt16]()
  1247  	case "int32":
  1248  		return reflect.TypeFor[int32]()
  1249  	case "nullint32":
  1250  		return reflect.TypeFor[NullInt32]()
  1251  	case "string":
  1252  		return reflect.TypeFor[string]()
  1253  	case "nullstring":
  1254  		return reflect.TypeFor[NullString]()
  1255  	case "int64":
  1256  		return reflect.TypeFor[int64]()
  1257  	case "nullint64":
  1258  		return reflect.TypeFor[NullInt64]()
  1259  	case "float64":
  1260  		return reflect.TypeFor[float64]()
  1261  	case "nullfloat64":
  1262  		return reflect.TypeFor[NullFloat64]()
  1263  	case "datetime":
  1264  		return reflect.TypeFor[time.Time]()
  1265  	case "any":
  1266  		return reflect.TypeFor[any]()
  1267  	}
  1268  	panic("invalid fakedb column type of " + typ)
  1269  }
  1270  

View as plain text