diff --git a/src/types/byte_range.rs b/src/types/byte_range.rs
index b8db803..af26870 100644
--- a/src/types/byte_range.rs
+++ b/src/types/byte_range.rs
@@ -43,3 +43,50 @@ impl FromStr for ByteRange {
         })
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_display() {
+        let byte_range = ByteRange {
+            length: 0,
+            start: Some(5),
+        };
+        assert_eq!(byte_range.to_string(), "0@5".to_string());
+
+        let byte_range = ByteRange {
+            length: 99999,
+            start: Some(2),
+        };
+        assert_eq!(byte_range.to_string(), "99999@2".to_string());
+
+        let byte_range = ByteRange {
+            length: 99999,
+            start: None,
+        };
+        assert_eq!(byte_range.to_string(), "99999".to_string());
+    }
+
+    #[test]
+    fn test_parse() {
+        let byte_range = ByteRange {
+            length: 99999,
+            start: Some(2),
+        };
+        assert_eq!(byte_range, "99999@2".parse::<ByteRange>().unwrap());
+
+        let byte_range = ByteRange {
+            length: 99999,
+            start: Some(2),
+        };
+        assert_eq!(byte_range, "99999@2".parse::<ByteRange>().unwrap());
+
+        let byte_range = ByteRange {
+            length: 99999,
+            start: None,
+        };
+        assert_eq!(byte_range, "99999".parse::<ByteRange>().unwrap());
+    }
+}
diff --git a/src/types/closed_captions.rs b/src/types/closed_captions.rs
index 1e1963f..fb4ed85 100644
--- a/src/types/closed_captions.rs
+++ b/src/types/closed_captions.rs
@@ -34,3 +34,29 @@ impl FromStr for ClosedCaptions {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_display() {
+        let closed_captions = ClosedCaptions::None;
+        assert_eq!(closed_captions.to_string(), "NONE".to_string());
+
+        let closed_captions = ClosedCaptions::GroupId(QuotedString::new("value").unwrap());
+        assert_eq!(closed_captions.to_string(), "\"value\"".to_string());
+    }
+
+    #[test]
+    fn test_parse() {
+        let closed_captions = ClosedCaptions::None;
+        assert_eq!(closed_captions, "NONE".parse::<ClosedCaptions>().unwrap());
+
+        let closed_captions = ClosedCaptions::GroupId(QuotedString::new("value").unwrap());
+        assert_eq!(
+            closed_captions,
+            "\"value\"".parse::<ClosedCaptions>().unwrap()
+        );
+    }
+}
diff --git a/src/types/decimal_floating_point.rs b/src/types/decimal_floating_point.rs
index 08c49fe..5cd33cc 100644
--- a/src/types/decimal_floating_point.rs
+++ b/src/types/decimal_floating_point.rs
@@ -68,3 +68,32 @@ impl FromStr for DecimalFloatingPoint {
         Ok(DecimalFloatingPoint(n))
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    pub fn test_display() {
+        let decimal_floating_point = DecimalFloatingPoint::new(22.0).unwrap();
+        assert_eq!(decimal_floating_point.to_string(), "22".to_string());
+
+        let decimal_floating_point = DecimalFloatingPoint::new(4.1).unwrap();
+        assert_eq!(decimal_floating_point.to_string(), "4.1".to_string());
+    }
+
+    #[test]
+    pub fn test_parse() {
+        let decimal_floating_point = DecimalFloatingPoint::new(22.0).unwrap();
+        assert_eq!(
+            decimal_floating_point,
+            "22".parse::<DecimalFloatingPoint>().unwrap()
+        );
+
+        let decimal_floating_point = DecimalFloatingPoint::new(4.1).unwrap();
+        assert_eq!(
+            decimal_floating_point,
+            "4.1".parse::<DecimalFloatingPoint>().unwrap()
+        );
+    }
+}
diff --git a/src/types/decimal_resolution.rs b/src/types/decimal_resolution.rs
index e340451..f323577 100644
--- a/src/types/decimal_resolution.rs
+++ b/src/types/decimal_resolution.rs
@@ -35,3 +35,44 @@ impl FromStr for DecimalResolution {
         })
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_display() {
+        let decimal_resolution = DecimalResolution {
+            width: 1920,
+            height: 1080,
+        };
+        assert_eq!(decimal_resolution.to_string(), "1920x1080".to_string());
+
+        let decimal_resolution = DecimalResolution {
+            width: 1280,
+            height: 720,
+        };
+        assert_eq!(decimal_resolution.to_string(), "1280x720".to_string());
+    }
+
+    #[test]
+    fn test_parse() {
+        let decimal_resolution = DecimalResolution {
+            width: 1920,
+            height: 1080,
+        };
+        assert_eq!(
+            decimal_resolution,
+            "1920x1080".parse::<DecimalResolution>().unwrap()
+        );
+
+        let decimal_resolution = DecimalResolution {
+            width: 1280,
+            height: 720,
+        };
+        assert_eq!(
+            decimal_resolution,
+            "1280x720".parse::<DecimalResolution>().unwrap()
+        );
+    }
+}
diff --git a/src/types/encryption_method.rs b/src/types/encryption_method.rs
index edd2911..971e7bb 100644
--- a/src/types/encryption_method.rs
+++ b/src/types/encryption_method.rs
@@ -37,3 +37,32 @@ impl FromStr for EncryptionMethod {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_display() {
+        let encryption_method = EncryptionMethod::Aes128;
+        assert_eq!(encryption_method.to_string(), "AES-128".to_string());
+
+        let encryption_method = EncryptionMethod::SampleAes;
+        assert_eq!(encryption_method.to_string(), "SAMPLE-AES".to_string());
+    }
+
+    #[test]
+    fn test_parse() {
+        let encryption_method = EncryptionMethod::Aes128;
+        assert_eq!(
+            encryption_method,
+            "AES-128".parse::<EncryptionMethod>().unwrap()
+        );
+
+        let encryption_method = EncryptionMethod::SampleAes;
+        assert_eq!(
+            encryption_method,
+            "SAMPLE-AES".parse::<EncryptionMethod>().unwrap()
+        );
+    }
+}
diff --git a/src/types/hdcp_level.rs b/src/types/hdcp_level.rs
index dacec45..436178f 100644
--- a/src/types/hdcp_level.rs
+++ b/src/types/hdcp_level.rs
@@ -33,3 +33,26 @@ impl FromStr for HdcpLevel {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_display() {
+        let level = HdcpLevel::Type0;
+        assert_eq!(level.to_string(), "TYPE-0".to_string());
+
+        let level = HdcpLevel::None;
+        assert_eq!(level.to_string(), "NONE".to_string());
+    }
+
+    #[test]
+    fn test_parse() {
+        let level = HdcpLevel::Type0;
+        assert_eq!(level, "TYPE-0".parse::<HdcpLevel>().unwrap());
+
+        let level = HdcpLevel::None;
+        assert_eq!(level, "NONE".parse::<HdcpLevel>().unwrap());
+    }
+}