diff --git a/cursor/cursor_test.go b/cursor/cursor_test.go
index 6072438..da406e0 100644
--- a/cursor/cursor_test.go
+++ b/cursor/cursor_test.go
@@ -7,7 +7,7 @@ import (
 
 	"git.codemonkeysoftware.net/b/gigaparsec/cursor"
 	ptest "git.codemonkeysoftware.net/b/gigaparsec/test"
-	"git.codemonkeysoftware.net/b/gigaparsec/test/generator"
+	pgen "git.codemonkeysoftware.net/b/gigaparsec/test/generator"
 	"github.com/shoenig/test"
 	"github.com/shoenig/test/must"
 	"pgregory.net/rapid"
@@ -17,18 +17,11 @@ func Todo(t *testing.T) {
 	t.Errorf("TODO")
 }
 
-// TODO move this to generator
-func SliceOfNZero[T any](minLen, maxLen int) *rapid.Generator[[]T] {
-	return rapid.Map(rapid.IntRange(minLen, maxLen), func(n int) []T {
-		return make([]T, n)
-	})
-}
-
 func testCursor[C cursor.Cursor[byte]](t *testing.T, makeCursor func([]byte) C) {
 	t.Helper()
 	t.Run("cursor reads the same position every time", rapid.MakeCheck(func(t *rapid.T) {
 		data := rapid.SliceOfN(rapid.Byte(), 1, 100).Draw(t, "data")
-		dst := SliceOfNZero[byte](0, len(data)-1).Draw(t, "dst")
+		dst := pgen.SliceOfNZero[byte](0, len(data)-1).Draw(t, "dst")
 		expected := data[:len(dst)]
 		c := makeCursor(data)
 
@@ -43,7 +36,7 @@ func testCursor[C cursor.Cursor[byte]](t *testing.T, makeCursor func([]byte) C)
 	}))
 	t.Run("Read returns io.EOF iff it overruns source", rapid.MakeCheck(func(t *rapid.T) {
 		data := rapid.SliceOfN(rapid.Byte(), 0, 100).Draw(t, "data")
-		dst := SliceOfNZero[byte](0, 200).Draw(t, "dst")
+		dst := pgen.SliceOfNZero[byte](0, 200).Draw(t, "dst")
 		c := makeCursor(data)
 
 		n, _, err := c.Read(dst)
@@ -114,9 +107,9 @@ func TestReaderAtCursor(t *testing.T) {
 		return cursor.NewReaderAt(bytes.NewReader(b))
 	})
 	t.Run("Read returns an error if the ReaderAt fails", rapid.MakeCheck(func(t *rapid.T) {
-		expectedErr := generator.Error().Draw(t, "expectedErr")
+		expectedErr := pgen.Error().Draw(t, "expectedErr")
 		startPos := rapid.Uint64().Draw(t, "startPos")
-		dst := SliceOfNZero[byte](0, 100).Draw(t, "dst")
+		dst := pgen.SliceOfNZero[byte](0, 100).Draw(t, "dst")
 		c := cursor.NewReaderAt(ptest.ErrReaderAt(expectedErr)).At(startPos)
 		n, next, err := c.Read(dst)
 		test.ErrorIs(t, err, expectedErr)
diff --git a/test/generator/gen.go b/test/generator/gen.go
index 6a63231..b0d4010 100644
--- a/test/generator/gen.go
+++ b/test/generator/gen.go
@@ -6,6 +6,15 @@ import (
 	"pgregory.net/rapid"
 )
 
+// Error returns a new error created by calling [errors.New] with a random string.
 func Error() *rapid.Generator[error] {
 	return rapid.Map(rapid.String(), errors.New)
 }
+
+// SliceOfNZero returns a generator that makes slices of the zero value of T.
+// The range of slice lengths are determined as in [rapid.SliceOfN].
+func SliceOfNZero[T any](minLen, maxLen int) *rapid.Generator[[]T] {
+	return rapid.Map(rapid.IntRange(minLen, maxLen), func(n int) []T {
+		return make([]T, n)
+	})
+}