utf8.RuneScanner.Buffered()

master
Charles Iliya Krempeaux 2023-11-30 07:22:18 -08:00
parent d38de8eb47
commit 6d4d82cd8f
2 changed files with 225 additions and 0 deletions

View File

@ -29,6 +29,25 @@ func NewRuneScanner(reader io.Reader) *RuneScanner {
return &runescanner
}
// Buffered returns the number of bytes the UTF-8 encoding of the current buffered rune takes up, if there is a buffered rune.
//
// A buffered rune would come from someone calleding .UnreadRune().
//
// If there is not buffered rune then .Buffered() returns zero (0).
//
// So, for example, if .UnreadRune() was called for the rune 'A' (U+0041), then .Buffered() would return 1.
//
// And, for example, if .UnreadRune() was called for the rune '🙂' (U+1F642), then .Buffered() would return 4.
//
// This method has been made to be semantically the same as bufio.Reader.Buffered()
func (receiver *RuneScanner) Buffered() int {
if !receiver.peeked {
return 0
}
return receiver.prevSize
}
func (receiver *RuneScanner) ReadRune() (rune, int, error) {
if nil == receiver {
return RuneError, 0, errNilReceiver

View File

@ -0,0 +1,206 @@
package utf8_test
import (
"testing"
"io"
"strings"
"sourcecode.social/reiver/go-utf8"
)
func TestRuneScanner_Buffered(t *testing.T) {
var s string = "🙂 apple 😈 banana 👾 cherry 🎃"
var reader io.Reader = strings.NewReader(s)
var runescanner utf8.RuneScanner = utf8.WrapRuneScanner(reader)
{
expected := 0
actual := runescanner.Buffered()
if expected != actual {
t.Errorf("The actual number of buffered-bytes is not was expected.")
t.Logf("EXPECTED: %d", expected)
t.Logf("ACTUAL: %d", actual)
return
}
}
{
r, n, err := runescanner.ReadRune()
if nil != err {
t.Errorf("Did not expect an error when trying to .ReadRune() but actually got one.")
t.Logf("ERROR: (%T) %s", err, err)
return
}
{
expected := '🙂'
actual := r
if expected != actual {
t.Errorf("The actual read rune is not what was expected.")
t.Logf("EXPECTED: %q (%U)", expected, expected)
t.Logf("ACTUAL: %q (%U)", actual, actual)
return
}
}
{
expected := 4
actual := n
if expected != actual {
t.Errorf("The actual number of bytes read is not what was expected.")
t.Logf("EXPECTED: %d", expected)
t.Logf("ACTUAL: %d", actual)
return
}
}
}
{
expected := 0
actual := runescanner.Buffered()
if expected != actual {
t.Errorf("The actual number of buffered-bytes is not was expected.")
t.Logf("EXPECTED: %d", expected)
t.Logf("ACTUAL: %d", actual)
return
}
}
{
err := runescanner.UnreadRune()
if nil != err {
t.Errorf("Did not expect an error when trying to .UnreadRune() but actually got one.")
t.Logf("ERROR: (%T) %s", err, err)
return
}
}
{
expected := 4
actual := runescanner.Buffered()
if expected != actual {
t.Errorf("The actual number of buffered-bytes is not was expected.")
t.Logf("EXPECTED: %d", expected)
t.Logf("ACTUAL: %d", actual)
return
}
}
{
r, n, err := runescanner.ReadRune()
if nil != err {
t.Errorf("Did not expect an error when trying to .ReadRune() but actually got one.")
t.Logf("ERROR: (%T) %s", err, err)
return
}
{
expected := '🙂'
actual := r
if expected != actual {
t.Errorf("The actual read rune is not what was expected.")
t.Logf("EXPECTED: %q (%U)", expected, expected)
t.Logf("ACTUAL: %q (%U)", actual, actual)
return
}
}
{
expected := 4
actual := n
if expected != actual {
t.Errorf("The actual number of bytes read is not what was expected.")
t.Logf("EXPECTED: %d", expected)
t.Logf("ACTUAL: %d", actual)
return
}
}
}
{
expected := 0
actual := runescanner.Buffered()
if expected != actual {
t.Errorf("The actual number of buffered-bytes is not was expected.")
t.Logf("EXPECTED: %d", expected)
t.Logf("ACTUAL: %d", actual)
return
}
}
{
r, n, err := runescanner.ReadRune()
if nil != err {
t.Errorf("Did not expect an error when trying to .ReadRune() but actually got one.")
t.Logf("ERROR: (%T) %s", err, err)
return
}
{
expected := ' '
actual := r
if expected != actual {
t.Errorf("The actual read rune is not what was expected.")
t.Logf("EXPECTED: %q (%U)", expected, expected)
t.Logf("ACTUAL: %q (%U)", actual, actual)
return
}
}
{
expected := 1
actual := n
if expected != actual {
t.Errorf("The actual number of bytes read is not what was expected.")
t.Logf("EXPECTED: %d", expected)
t.Logf("ACTUAL: %d", actual)
return
}
}
}
{
expected := 0
actual := runescanner.Buffered()
if expected != actual {
t.Errorf("The actual number of buffered-bytes is not was expected.")
t.Logf("EXPECTED: %d", expected)
t.Logf("ACTUAL: %d", actual)
return
}
}
{
err := runescanner.UnreadRune()
if nil != err {
t.Errorf("Did not expect an error when trying to .UnreadRune() but actually got one.")
t.Logf("ERROR: (%T) %s", err, err)
return
}
}
{
expected := 1
actual := runescanner.Buffered()
if expected != actual {
t.Errorf("The actual number of buffered-bytes is not was expected.")
t.Logf("EXPECTED: %d", expected)
t.Logf("ACTUAL: %d", actual)
return
}
}
}