diff --git a/internal/tailer/file_test.go b/internal/tailer/file_test.go
index 18593e15f..6a12cf891 100644
--- a/internal/tailer/file_test.go
+++ b/internal/tailer/file_test.go
@@ -49,10 +49,8 @@ func TestReadPartial(t *testing.T) {
 	if f.partial.String() != "" {
 		t.Errorf("partial line not empty: %q", f.partial)
 	}
-	_, err = fd.WriteString("o")
-	testutil.FatalIfErr(t, err)
-	_, err = fd.WriteString("hi")
-	testutil.FatalIfErr(t, err)
+	testutil.WriteString(t, fd, "o")
+	testutil.WriteString(t, fd, "hi")
 	// memmapfs shares data structure here and in code under test so reset the file offset
 	_, err = fd.Seek(0, 0)
 	testutil.FatalIfErr(t, err)
@@ -66,8 +64,7 @@ func TestReadPartial(t *testing.T) {
 	// reset the cursor again
 	_, err = fd.Seek(3, io.SeekStart)
 	testutil.FatalIfErr(t, err)
-	_, err = fd.WriteString("\n")
-	testutil.FatalIfErr(t, err)
+	testutil.WriteString(t, fd, "\n")
 	_, err = fd.Seek(-1, io.SeekEnd)
 	testutil.FatalIfErr(t, err)
 	err = f.Read()
diff --git a/internal/tailer/tail_test.go b/internal/tailer/tail_test.go
index 69d170b74..87dd7213e 100644
--- a/internal/tailer/tail_test.go
+++ b/internal/tailer/tail_test.go
@@ -74,10 +74,7 @@ func TestHandleLogUpdate(t *testing.T) {
 	}
 
 	wg.Add(4)
-	_, err = f.WriteString("a\nb\nc\nd\n")
-	if err != nil {
-		t.Fatal(err)
-	}
+	testutil.WriteString(t, f, "a\nb\nc\nd\n")
 	// f.Seek(0, 0)
 	w.InjectUpdate(logfile)
 
@@ -183,15 +180,12 @@ func TestHandleLogUpdatePartialLine(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	_, err = f.WriteString("a")
-	if err != nil {
-		t.Fatal(err)
-	}
+	testutil.WriteString(t, f, "a")
 	//f.Seek(0, 0)
 	w.InjectUpdate(logfile)
 
 	//f.Seek(1, 0)
-	_, err = f.WriteString("b")
+	testutil.WriteString(t, f, "b")
 	if err != nil {
 		t.Error(err)
 	}
@@ -199,10 +193,7 @@ func TestHandleLogUpdatePartialLine(t *testing.T) {
 	w.InjectUpdate(logfile)
 
 	//f.Seek(2, 0)
-	_, err = f.WriteString("\n")
-	if err != nil {
-		t.Error(err)
-	}
+	testutil.WriteString(t, f, "\n")
 	//f.Seek(2, 0)
 	w.InjectUpdate(logfile)