diff --git a/file_test.go b/file_test.go
index 5490aad..8815d05 100644
--- a/file_test.go
+++ b/file_test.go
@@ -30,3 +30,84 @@ func TestFile_SetGetHeader(t *testing.T) {
 		t.Errorf("getHeader returned wrong value. Expected: %s, got: %s", "", fi)
 	}
 }
+
+// TestFile_WithFileDescription tests the WithFileDescription option
+func TestFile_WithFileDescription(t *testing.T) {
+	tests := []struct {
+		name string
+		desc string
+	}{
+		{"File description: test", "test"},
+		{"File description: empty", ""},
+	}
+	for _, tt := range tests {
+		m := NewMsg()
+		t.Run(tt.name, func(t *testing.T) {
+			m.AttachFile("file.go", WithFileDescription(tt.desc))
+			al := m.GetAttachments()
+			if len(al) <= 0 {
+				t.Errorf("AttachFile() failed. Attachment list is empty")
+			}
+			a := al[0]
+			if a.Desc != tt.desc {
+				t.Errorf("WithFileDescription() failed. Expected: %s, got: %s", tt.desc, a.Desc)
+			}
+		})
+	}
+}
+
+// TestFile_WithFileEncoding tests the WithFileEncoding option
+func TestFile_WithFileEncoding(t *testing.T) {
+	tests := []struct {
+		name string
+		enc  Encoding
+		want Encoding
+	}{
+		{"File encoding: 8bit raw", NoEncoding, NoEncoding},
+		{"File encoding: Base64", EncodingB64, EncodingB64},
+		{"File encoding: quoted-printable (not allowed)", EncodingQP, ""},
+	}
+	for _, tt := range tests {
+		m := NewMsg()
+		t.Run(tt.name, func(t *testing.T) {
+			m.AttachFile("file.go", WithFileEncoding(tt.enc))
+			al := m.GetAttachments()
+			if len(al) <= 0 {
+				t.Errorf("AttachFile() failed. Attachment list is empty")
+			}
+			a := al[0]
+			if a.Enc != tt.want {
+				t.Errorf("WithFileEncoding() failed. Expected: %s, got: %s", tt.enc, a.Enc)
+			}
+		})
+	}
+}
+
+// TestFile_WithFileContentType tests the WithFileContentType option
+func TestFile_WithFileContentType(t *testing.T) {
+	tests := []struct {
+		name string
+		ct   ContentType
+		want string
+	}{
+		{"File content-type: text/plain", TypeTextPlain, "text/plain"},
+		{"File content-type: html/html", TypeTextHTML, "text/html"},
+		{"File content-type: application/octet-stream", TypeAppOctetStream, "application/octet-stream"},
+		{"File content-type: application/pgp-encrypted", TypePGPEncrypted, "application/pgp-encrypted"},
+		{"File content-type: application/pgp-signature", TypePGPSignature, "application/pgp-signature"},
+	}
+	for _, tt := range tests {
+		m := NewMsg()
+		t.Run(tt.name, func(t *testing.T) {
+			m.AttachFile("file.go", WithFileContentType(tt.ct))
+			al := m.GetAttachments()
+			if len(al) <= 0 {
+				t.Errorf("AttachFile() failed. Attachment list is empty")
+			}
+			a := al[0]
+			if a.ContentType != ContentType(tt.want) {
+				t.Errorf("WithFileContentType() failed. Expected: %s, got: %s", tt.want, a.ContentType)
+			}
+		})
+	}
+}