diff --git a/input_scv.go b/input_csv.go
similarity index 100%
rename from input_scv.go
rename to input_csv.go
diff --git a/input_csv_test.go b/input_csv_test.go
new file mode 100644
index 0000000..fd1aed0
--- /dev/null
+++ b/input_csv_test.go
@@ -0,0 +1,29 @@
+package script_test
+
+import (
+	"slices"
+	"testing"
+
+	"code.uint32.ru/dmitry/script"
+)
+
+func TestCSVReader(t *testing.T) {
+	t.Parallel()
+	r, err := script.NewCSVReader("testdata/sample_csv.csv")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	want := []string{"one", "two", "three"}
+
+	for range 2 {
+		row, err := r.Read()
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		if !slices.Equal(row, want) {
+			t.Fatalf("rows not equal, want: %v, have: %v", want, row)
+		}
+	}
+}
diff --git a/output_csv_test.go b/output_csv_test.go
new file mode 100644
index 0000000..6a23385
--- /dev/null
+++ b/output_csv_test.go
@@ -0,0 +1,42 @@
+package script
+
+import (
+	"bytes"
+	"os"
+	"testing"
+)
+
+func TestCSVWriter(t *testing.T) {
+	path := "testdata/output_csv.csv"
+
+	os.Remove(path)
+	defer os.Remove(path)
+
+	w, err := newCSVwriter(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	want := []byte("one,two,three\none,two,three\n")
+
+	row := []string{"one", "two", "three"}
+
+	for range 2 {
+		if err := w.Write(row); err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	if err := w.Close(); err != nil {
+		t.Fatal(err)
+	}
+
+	b, err := os.ReadFile(path)
+	if err != nil {
+		t.Fatalf("err reading output file: %s", err)
+	}
+
+	if !bytes.Equal(want, b) {
+		t.Errorf("incorrect result, want: %s, have: %s", string(want), string(b))
+	}
+}
diff --git a/testdata/sample_csv.csv b/testdata/sample_csv.csv
new file mode 100644
index 0000000..42753f1
--- /dev/null
+++ b/testdata/sample_csv.csv
@@ -0,0 +1,2 @@
+one,two,three
+one,two,three