initial import

core/filex/rangereader_test.go

@@ -0,0 +1,45 @@
+package filex
+
+import (
+	"os"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"zero/core/fs"
+)
+
+func TestRangeReader(t *testing.T) {
+	const text = `hello
+world`
+	file, err := fs.TempFileWithText(text)
+	assert.Nil(t, err)
+	defer func() {
+		file.Close()
+		os.Remove(file.Name())
+	}()
+
+	reader := NewRangeReader(file, 5, 8)
+	buf := make([]byte, 10)
+	n, err := reader.Read(buf)
+	assert.Nil(t, err)
+	assert.Equal(t, 3, n)
+	assert.Equal(t, `
+wo`, string(buf[:n]))
+}
+
+func TestRangeReader_OutOfRange(t *testing.T) {
+	const text = `hello
+world`
+	file, err := fs.TempFileWithText(text)
+	assert.Nil(t, err)
+	defer func() {
+		file.Close()
+		os.Remove(file.Name())
+	}()
+
+	reader := NewRangeReader(file, 50, 8)
+	buf := make([]byte, 10)
+	_, err = reader.Read(buf)
+	assert.NotNil(t, err)
+}