feat: add optional serde support for *Type enums

Author: Lepidopteran

lofty/Cargo.toml

@@ -30,6 +30,12 @@ paste         = "1.0.15"
 [features]
 default                   = ["id3v2_compression_support"]
 id3v2_compression_support = ["dep:flate2"]
+serde = ["dep:serde"]
+
+[dependencies.serde]
+version = "1.0"
+features = ["derive"]
+optional = true
 
 [dev-dependencies]
 # WAV properties validity tests

lofty/src/file/file_type.rs

@@ -6,6 +6,7 @@ use std::ffi::OsStr;
 use std::path::Path;
 
 /// The type of file read
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 #[derive(PartialEq, Eq, Copy, Clone, Debug)]
 #[allow(missing_docs)]
 #[non_exhaustive]

lofty/src/picture.rs

@@ -38,6 +38,7 @@ pub const APE_PICTURE_TYPES: [&str; 21] = [
 ];
 
 /// MIME types for pictures.
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 #[derive(Debug, Clone, Eq, PartialEq, Hash)]
 #[non_exhaustive]
 pub enum MimeType {
@@ -130,6 +131,7 @@ impl Display for MimeType {
 
 /// The picture type, according to ID3v2 APIC
 #[allow(missing_docs)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 #[derive(Debug, Clone, Copy, Eq, PartialEq, Hash)]
 #[non_exhaustive]
 pub enum PictureType {
@@ -279,6 +281,7 @@ impl PictureType {
 ///
 /// This information is necessary for FLAC's `METADATA_BLOCK_PICTURE`.
 /// See [`Picture::as_flac_bytes`] for more information.
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 #[derive(Debug, Copy, Clone, Eq, PartialEq, Hash, Default)]
 pub struct PictureInformation {
 	/// The picture's width in pixels

lofty/src/tag/tag_type.rs

@@ -10,6 +10,7 @@ use std::fs::OpenOptions;
 use std::path::Path;
 
 /// The tag's format
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
 #[non_exhaustive]
 pub enum TagType {