Example #1
0
func testBuffer() {
	var b bytes.Buffer
	check(b.String(), "") // String() on fresh variable
	b.Reset()             // Reset() on fresh variable
	check(b.String(), "") // String() after Reset()
	b.Reset()             // Reset() after Reset()
	check(b.String(), "")
	check(b.Len(), 0)

	// same tests as above with pointer
	b2 := &bytes.Buffer{}
	check(b2.String(), "")
	b2.Reset()
	check(b2.String(), "")
	b2.Reset()
	check(b2.String(), "")
	check(b2.Len(), 0)

	b2.WriteString("Dies ist ein Test!")
	check(b2.String(), "Dies ist ein Test!")
	check(b2.Len(), 18)

	n, err := b.Write(nil)
	check(n, 0)
	check(err, nil)
	check(b.String(), "")

	n, err = b.Write([]byte{})
	check(n, 0)
	check(err, nil)
	check(b.String(), "")
	check(b.Pointer(), nil)
	check(b.Capacity(), 0)
	check(b.Len(), 0)

	func() {
		defer func() {
			check(recover(), bytes.ErrTooLarge)
		}()
		b.Grow(-1)
	}()

	n, err = b.Write([]byte{'a'})
	check(n, 1)
	check(err, nil)
	check(b.String(), "a")
	check(b.Capacity() >= 1, true)
	check(b.Len(), 1)
	check(b.Pointer() != nil, true)

	check(b.Grow(11), 1)
	check(b.Capacity() >= 12, true)
	c := b.Capacity()
	p := b.Pointer()
	check(b.Grow(11), 1) // should not cause actual growth
	check(b.Pointer(), p)
	check(b.Capacity(), c)
	check(b.Len(), 1)
	((*[2]byte)(b.Pointer()))[1] = 'z'
	check(b.Contains("z"), false)

	n, err = b.WriteString("Hallo")
	check(n, 5)
	check(err, nil)
	check(b.String(), "aHallo")
	check(b.Pointer(), p)
	check(b.Capacity(), c)
	check(b.Len(), 6)

	b.Reset()
	check(b.String(), "")
	check(b.Pointer(), nil)
	check(b.Capacity(), 0)
	check(b.Contains(""), true)
	check(b.Contains("a"), false)

	b.WriteString("Hallo")
	b.WriteByte(' ')
	b.Write([]byte{'d', 'i', 'e', 's'})
	b.WriteByte(' ')
	b.WriteString("ist ")
	b.WriteString("ein ")
	b.Write([]byte("Test"))
	check(b.String(), "Hallo dies ist ein Test")
	check(b.Contains("Hallo dies ist ein Test"), true)
	check(b.Contains("Test"), true)
	check(b.Contains("Hallo"), true)
	check(b.Contains("allo"), true)
	check(b.Contains(""), true)

	check(b.Split(" "), []string{"Hallo", "dies", "ist", "ein", "Test"})
	check(b.Split("X"), []string{"Hallo dies ist ein Test"})
	check(b.Split("Hallo dies ist ein Test"), []string{"", ""})
	check(b.Split("H"), []string{"", "allo dies ist ein Test"})
	check(b.Split("Test"), []string{"Hallo dies ist ein ", ""})
	check(b.Split("es"), []string{"Hallo di", " ist ein T", "t"})

	b.Reset()
	b.WriteString("  \n\t Hallo  \t\v\n")
	check(b.Len(), 15)
	p = b.Pointer()
	b.TrimSpace()
	check(b.String(), "Hallo")
	check(b.Len(), 5)
	check(b.Pointer(), p)

	b.Reset()
	b.WriteString("  \n\t   \t\v\n")
	check(b.Len(), 10)
	b.TrimSpace()
	check(b.Pointer(), nil)
	check(b.Len(), 0)
	check(b.Capacity(), 0)
	b.TrimSpace()
	check(b.Pointer(), nil)
	check(b.Len(), 0)
	check(b.Capacity(), 0)

	b.Reset()
	b.WriteString("  \n\t Hallo")
	check(b.Len(), 10)
	p = b.Pointer()
	b.TrimSpace()
	check(b.String(), "Hallo")
	check(b.Len(), 5)
	check(b.Pointer(), p)

	b.Reset()
	b.WriteString("Hallo  \t\v\n")
	check(b.Len(), 10)
	p = b.Pointer()
	b.TrimSpace()
	check(b.String(), "Hallo")
	check(b.Len(), 5)
	check(b.Pointer(), p)

	b.Reset()
	b.WriteString(" ")
	check(b.Len(), 1)
	b.TrimSpace()
	check(b.Pointer(), nil)
	check(b.Len(), 0)
	check(b.Capacity(), 0)

	b.Reset()
	b.WriteString("Der Cottbuser Postkutscher kotzt in den Cottbuser Postkotzkasten")
	n = b.Len()
	c = b.Capacity()
	p = b.Pointer()
	b.Trim(-10, 2000)
	check(b.Len(), n)
	check(b.Capacity(), c)
	check(b.Pointer(), p)

	b.Trim(2000, -10)
	check(b.Len(), 0)
	check(b.Capacity(), 0)
	check(b.Pointer(), nil)

	b.WriteString("Der Cottbuser Postkutscher kotzt in den Cottbuser Postkotzkasten")
	b.Trim(4, 4)
	check(b.Len(), 0)
	check(b.Capacity(), 0)
	check(b.Pointer(), nil)

	b.WriteString("Der Cottbuser Postkutscher kotzt in den Cottbuser Postkotzkasten")
	n = b.Len()
	c = b.Capacity()
	p = b.Pointer()
	b.Trim(0, b.Len()-6)
	check(b.Len(), n-6)
	check(b.Capacity(), c)
	check(b.Pointer(), p)
	check(b.String(), "Der Cottbuser Postkutscher kotzt in den Cottbuser Postkotz")

	b.Trim(27, b.Len())
	check(b.Len(), n-6-27)
	check(b.Capacity(), c)
	check(b.Pointer(), p)
	check(b.String(), "kotzt in den Cottbuser Postkotz")

	b.Trim(1, b.Len()-1)
	check(b.Len(), n-6-27-2)
	check(b.Capacity(), c)
	check(b.Pointer(), p)
	check(b.String(), "otzt in den Cottbuser Postkot")

	b.Reset()
	b.Write0(-1)
	b.Write0(-100)
	b.Write0(0)
	check(b.Len(), 0)
	check(b.Capacity(), 0)
	check(b.Pointer(), nil)

	b.Write0(1)
	check(b.Len(), 1)
	check(b.Capacity(), 1)
	check(b.Bytes(), []byte{0})

	b.WriteByte(111)
	b.Write0(1)
	b.WriteByte(222)
	b.Write0(2)
	b.WriteByte(99)
	check(b.Len(), 7)
	check(b.Bytes(), []byte{0, 111, 0, 222, 0, 0, 99})

	b2.Reset()
	slices := [][]byte{}
	total := 0
	numfakeerrs := 0
	for total < 100000 {
		c = rand.Intn(30000)
		total += c

		sl := make([]byte, c)
		for i := range sl {
			sl[i] = byte(rand.Intn(256))
		}
		slices = append(slices, sl)
		b2.Write(sl)

		if total/30000 > numfakeerrs {
			slices = append(slices, nil)
			numfakeerrs++
		}
	}

	check(numfakeerrs, 3)

	slcopy := make([][]byte, len(slices))
	copy(slcopy, slices)
	slret := &sliceReturner{Slices: slcopy}
	b.Reset()
	check(b.Capacity(), 0)
	check(b.Len(), 0)
	check(b.Pointer(), nil)
	n = 0
	for i := 0; i < numfakeerrs; i++ {
		n64, err := b.ReadFrom(slret)
		n += int(n64)
		check(err, FakeError)
	}
	n64, err := b.ReadFrom(slret)
	n += int(n64)
	check(err, nil)
	check(n, total)
	check(b.Capacity() > b.Len(), true)
	check(b.Len(), total)

	contents := b.Bytes()
	contents2 := b2.Bytes()
	check(len(contents), len(contents2))
	n = 0
	for i := range contents {
		if contents[i] != contents2[i] {
			break
		}
		n++
	}
	check(n, total)

	b2.Reset()
	for i := range slices {
		for k := range slices[i] {
			slices[i][k] = 11
		}
		n, err = b.Read(slices[i])
		check(n, len(slices[i]))
		check(err, nil)
		b2.Write(slices[i])
	}

	check(b2.Len(), total)

	n, err = b.Read(slices[0])
	check(n, 0)
	check(err, io.EOF)

	contents = b.Bytes()
	contents2 = b2.Bytes()
	check(len(contents), len(contents2))
	n = 0
	for i := range contents {
		if contents[i] != contents2[i] {
			break
		}
		n++
	}
	check(n, total)

	b.WriteString("foo")
	foo := make([]byte, 10)
	n, err = b.Read(foo)
	check(n, 3)
	check(err, nil)
	check(string(foo[0:3]), "foo")

	n64, err = b.Seek(6700, 0)
	check(n64, 6700)
	check(err, nil)

	n64, err = b.Seek(-6000, 1)
	check(n64, 700)
	check(err, nil)

	n64, err = b.Seek(815, 1)
	check(n64, 1515)
	check(err, nil)
	n, err = b.Read(foo)
	check(n, len(foo))
	check(err, nil)
	check(foo, b2.Bytes()[1515:1515+len(foo)])

	n64, err = b.Seek(-3, 2)
	check(n64, total)
	check(err, nil)
	n, err = b.Read(foo)
	check(n, 3)
	check(err, nil)
	check(string(foo[0:3]), "foo")

	n64, err = b.Seek(999999, 0)
	check(n64, b.Len())
	check(err, nil)
	n64, err = b.Seek(-3, 1)
	check(n64, total)
	check(err, nil)
	n, err = b.Read(foo)
	check(n, 3)
	check(err, nil)
	check(string(foo[0:3]), "foo")

	n64, err = b.Seek(-815, 0)
	check(n64, 0)
	check(err, nil)
	n, err = b.Read(foo)
	check(n, len(foo))
	check(err, nil)
	check(foo, b2.Bytes()[0:len(foo)])
}