Test Repeat success/failure

test/helpers.go

@@ -0,0 +1,36 @@
+// SPDX-License-Identifier: Unlicense
+
+// Package test contains helpers for testing parsers.
+package test
+
+import (
+	"io"
+
+	"git.codemonkeysoftware.net/b/gigaparsec"
+	"github.com/shoenig/test"
+)
+
+type errReaderAt struct {
+	err error
+}
+
+func (r errReaderAt) ReadAt([]byte, int64) (int, error) {
+	return 0, r.err
+}
+
+// ErrReaderAt returns an [io.ReaderAt] with a ReadAt method that always returns err.
+func ErrReaderAt(err error) io.ReaderAt {
+	return errReaderAt{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()))
+}
+
+func SliceOfN[T any](value T, n int) []T {
+	s := make([]T, n)
+	for i := range s {
+		s[i] = value
+	}
+	return s
+}