Add local file abstraction

ipblocklist/files/local_test.go

@@ -0,0 +1,55 @@
+package files_test
+
+import (
+	"context"
+	"io"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"github.com/9seconds/mtg/v2/ipblocklist/files"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/suite"
+)
+
+type LocalTestSuite struct {
+	suite.Suite
+}
+
+func (suite *LocalTestSuite) GetLocalFile(name string) string {
+	return filepath.Join("testdata", name)
+}
+
+func (suite *LocalTestSuite) TestIncorrect() {
+	names := []string{
+		"absent",
+		"directory",
+	}
+
+	for _, v := range names {
+		value := v
+
+		suite.T().Run(v, func(t *testing.T) {
+			_, err := files.NewLocal(suite.GetLocalFile(value))
+			assert.Error(t, err)
+		})
+	}
+}
+
+func (suite *LocalTestSuite) TestOk() {
+	file, err := files.NewLocal(suite.GetLocalFile("readable"))
+	suite.NoError(err)
+
+	reader, err := file.Open(context.Background())
+	suite.NoError(err)
+
+	data, err := io.ReadAll(reader)
+	suite.NoError(err)
+
+	suite.Equal("Hooray!", strings.TrimSpace(string(data)))
+}
+
+func TestLocal(t *testing.T) {
+	t.Parallel()
+	suite.Run(t, &LocalTestSuite{})
+}