Added MatchString

This commit is contained in:
Brandon Dyck 2024-09-24 11:53:32 -06:00
parent 51f3532d64
commit 447058020f
3 changed files with 68 additions and 3 deletions

View File

@ -3,6 +3,7 @@
package bytes
import (
"bytes"
"errors"
"fmt"
"io"
@ -87,3 +88,22 @@ func Regexp(pattern string) gigaparsec.Parser[byte, string] {
return gigaparsec.Succeed(true, string(dst), next, gigaparsec.MessageOK(input.Pos())), nil
}
}
func MatchString(s string) gigaparsec.Parser[byte, string] {
expected := fmt.Sprintf("%q", s)
b := []byte(s)
return func(input gigaparsec.State[byte]) (gigaparsec.Result[byte, string], error) {
dst := make([]byte, len(s))
_, next, err := input.Read(dst)
if errors.Is(err, io.EOF) {
return gigaparsec.Fail[byte, string](false, gigaparsec.MessageEnd(input.Pos(), expected)), nil
}
if err != nil {
return gigaparsec.Result[byte, string]{}, fmt.Errorf("MatchString: %w", err)
}
if !bytes.Equal(dst, b) {
return gigaparsec.Fail[byte, string](false, gigaparsec.MakeMessage(input.Pos(), string(dst), expected)), nil
}
return gigaparsec.Succeed(true, s, next, gigaparsec.MessageOK(input.Pos())), nil
}
}

View File

@ -3,11 +3,14 @@
package bytes_test
import (
"bytes"
"testing"
"git.codemonkeysoftware.net/b/gigaparsec"
"git.codemonkeysoftware.net/b/gigaparsec/bytes"
pbytes "git.codemonkeysoftware.net/b/gigaparsec/bytes"
"git.codemonkeysoftware.net/b/gigaparsec/cursor"
ptest "git.codemonkeysoftware.net/b/gigaparsec/test"
pgen "git.codemonkeysoftware.net/b/gigaparsec/test/generator"
"github.com/shoenig/test"
"github.com/shoenig/test/must"
"pgregory.net/rapid"
@ -25,7 +28,7 @@ func TestRegexp(t *testing.T) {
}))
t.Run("basically works", func(t *testing.T) {
result, err := bytes.Regexp("a")(gigaparsec.MakeState(cursor.NewSlice([]byte("a"))))
result, err := pbytes.Regexp("a")(gigaparsec.MakeState(cursor.NewSlice([]byte("a"))))
must.NoError(t, err)
failed, _, msg := result.Failed()
must.False(t, failed, must.Sprint(msg))
@ -38,7 +41,7 @@ func TestRegexp(t *testing.T) {
func TestRuneReader(t *testing.T) {
var s = []byte("abcdefghijklmnopqrstuvwxyz")
rr := bytes.NewRuneReader(cursor.NewSlice(s))
rr := pbytes.NewRuneReader(cursor.NewSlice(s))
for i, b := range s {
r, n, err := rr.ReadRune()
test.NoError(t, err)
@ -49,3 +52,39 @@ func TestRuneReader(t *testing.T) {
}
}
}
func TestMatchString(t *testing.T) {
t.Run("fails on unexpected error", rapid.MakeCheck(func(t *rapid.T) {
s := rapid.StringN(-1, -1, 100).Draw(t, "s")
readErr := pgen.Error().Draw(t, "readErr")
result, err := pbytes.MatchString(s)(gigaparsec.MakeState(cursor.NewReaderAt(ptest.ErrReaderAt(readErr))))
test.ErrorIs(t, err, readErr)
failed, consumed, _ := result.Failed()
test.True(t, failed)
test.False(t, consumed)
}))
t.Run("does not succeed or consume on mismatch", rapid.MakeCheck(func(t *rapid.T) {
bgen := rapid.SliceOfN(rapid.Byte(), 1, 100)
input := bgen.Draw(t, "input")
notPrefix := func(b []byte) bool { return !bytes.HasPrefix(input, b) }
s := string(bgen.Filter(notPrefix).Draw(t, "s"))
result, err := pbytes.MatchString(s)(gigaparsec.MakeState(cursor.NewSlice(input)))
must.NoError(t, err)
failed, consumed, _ := result.Failed()
must.True(t, failed)
test.False(t, consumed)
}))
t.Run("succeeds with correct value, consumption, and position", rapid.MakeCheck(func(t *rapid.T) {
input := rapid.SliceOfN(rapid.Byte(), 1, 100).Draw(t, "input")
slen := rapid.IntRange(0, len(input)).Draw(t, "slen")
s := string(input[:slen])
result, err := pbytes.MatchString(s)(gigaparsec.MakeState(cursor.NewSlice(input)))
must.NoError(t, err)
succeeded, consumed, value, next, _ := result.Succeeded()
must.True(t, succeeded)
test.True(t, consumed)
test.EqOp(t, s, value)
ptest.StateIsAt(t, next, uint64(slen))
}))
}

View File

@ -6,7 +6,9 @@ package test
import (
"io"
"git.codemonkeysoftware.net/b/gigaparsec"
"git.codemonkeysoftware.net/b/gigaparsec/cursor"
"github.com/shoenig/test"
)
type errReaderAt struct {
@ -44,3 +46,7 @@ func (c errCursor[T]) Pos() uint64 {
func ErrCursor[T any](err error) cursor.Cursor[T] {
return errCursor[T]{err: err}
}
func StateIsAt[Input any](t test.T, s gigaparsec.State[Input], pos uint64) {
test.EqOp(t, pos, s.Pos(), test.Sprintf("expected parser state to be at position %d, got %d", pos, s.Pos()))
}