perf: inline performance-critical operations

* Standardize inlining of simple, frequently-used operations
* Focus on performance-critical audio processing paths
* Inline UUID operations (deref, display, conversion, generation)
* Inline numeric type conversions in util module

CHANGELOG.md

@@ -10,6 +10,7 @@ and [Conventional Commits](https://www.conventionalcommits.org/en/v1.0.0/).
 ### Changed
 - [decrypt] Add explicit `BufRead` implementation to standardize buffering behavior
 - [decrypt] Inline performance-critical buffer operations
+- [docs] Remove incorrect mention of "Hi-Res" audio quality
 
 ## [0.8.1] - 2025-01-11
 

src/arl.rs

@@ -87,6 +87,7 @@ impl Arl {
     /// assert!(Arl::new("spaces not allowed".to_string()).is_err());
     /// assert!(Arl::new("控制字符".to_string()).is_err());
     /// ```
+    #[inline]
     pub fn new(arl: String) -> Result<Self> {
         Ok(Self(arl))
     }
@@ -110,6 +111,7 @@ impl Deref for Arl {
     /// validation invariants.
     type Target = String;
 
+    #[inline]
     fn deref(&self) -> &Self::Target {
         &self.0
     }
@@ -135,6 +137,7 @@ impl Deref for Arl {
 /// println!("{:?}", arl);  // Prints: Arl("REDACTED")
 /// ```
 impl fmt::Display for Arl {
+    #[inline]
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         write!(f, "{}", self.0)
     }

src/gateway.rs

@@ -362,6 +362,7 @@ impl Gateway {
     ///
     /// The license token is required for media access.
     #[must_use]
+    #[inline]
     pub fn license_token(&self) -> Option<&str> {
         self.user_data
             .as_ref()
@@ -374,6 +375,7 @@ impl Gateway {
     /// * No user data is available
     /// * Current time is past expiration time
     #[must_use]
+    #[inline]
     pub fn is_expired(&self) -> bool {
         self.expires_at() <= SystemTime::now()
     }
@@ -382,6 +384,7 @@ impl Gateway {
     ///
     /// Returns UNIX epoch if no session is active.
     #[must_use]
+    #[inline]
     pub fn expires_at(&self) -> SystemTime {
         if let Some(data) = &self.user_data {
             return data.user.options.expiration_timestamp;
@@ -391,12 +394,14 @@ impl Gateway {
     }
 
     /// Updates the cached user data.
+    #[inline]
     pub fn set_user_data(&mut self, data: UserData) {
         self.user_data = Some(data);
     }
 
     /// Returns a reference to the current user data if available.
     #[must_use]
+    #[inline]
     pub fn user_data(&self) -> Option<&UserData> {
         self.user_data.as_ref()
     }
@@ -430,6 +435,7 @@ impl Gateway {
 
     /// Returns the user's display name if available.
     #[must_use]
+    #[inline]
     pub fn user_name(&self) -> Option<&str> {
         self.user_data.as_ref().map(|data| data.user.name.as_str())
     }
@@ -601,6 +607,7 @@ impl Gateway {
     ///
     /// Forces a refresh on next token request while preserving
     /// other API functionality.
+    #[inline]
     pub fn flush_user_token(&mut self) {
         // Force refreshing user data, but do not set `user_data` to `None` so
         // so we can continue using the `api_token` it contains.

src/http.rs

@@ -205,6 +205,7 @@ impl Client {
     /// );
     /// let response = client.execute(request).await?;
     /// ```
+    #[inline]
     pub fn request<U, T>(&self, method: Method, url: U, body: T) -> reqwest::Request
     where
         U: Into<Url>,
@@ -225,6 +226,7 @@ impl Client {
     ///
     /// * `url` - Request URL
     /// * `body` - Request body content
+    #[inline]
     pub fn post<U, T>(&self, url: U, body: T) -> reqwest::Request
     where
         U: Into<Url>,
@@ -241,6 +243,7 @@ impl Client {
     ///
     /// * `url` - Request URL
     /// * `body` - Request body content (usually empty)
+    #[inline]
     pub fn get<U, T>(&self, url: U, body: T) -> reqwest::Request
     where
         U: Into<Url>,

src/player.rs

@@ -990,12 +990,14 @@ impl Player {
 
     /// Returns the currently playing track, if any.
     #[must_use]
+    #[inline]
     pub fn track(&self) -> Option<&Track> {
         self.queue.get(self.position)
     }
 
     /// Returns a mutable reference to the currently playing track, if any.
     #[must_use]
+    #[inline]
     pub fn track_mut(&mut self) -> Option<&mut Track> {
         self.queue.get_mut(self.position)
     }
@@ -1015,13 +1017,15 @@ impl Player {
 
     /// Returns a reference to the next track in the queue, if any.
     #[must_use]
+    #[inline]
     pub fn next_track(&self) -> Option<&Track> {
         let next = self.position.saturating_add(1);
         self.queue.get(next)
     }
 
     /// Returns a mutable reference to the next track in the queue, if any.
     #[must_use]
+    #[inline]
     pub fn next_track_mut(&mut self) -> Option<&mut Track> {
         let next = self.position.saturating_add(1);
         self.queue.get_mut(next)
@@ -1154,6 +1158,7 @@ impl Player {
 
     /// Returns the current repeat mode.
     #[must_use]
+    #[inline]
     pub fn repeat_mode(&self) -> RepeatMode {
         self.repeat_mode
     }
@@ -1186,6 +1191,7 @@ impl Player {
     ///
     /// Note: This returns the stored volume setting even if the audio device is closed.
     #[must_use]
+    #[inline]
     pub fn volume(&self) -> Percentage {
         self.volume
     }
@@ -1425,16 +1431,19 @@ impl Player {
 
     /// Returns current position in the queue.
     #[must_use]
+    #[inline]
     pub fn position(&self) -> usize {
         self.position
     }
 
     /// Sets the license token for media access.
+    #[inline]
     pub fn set_license_token(&mut self, license_token: impl Into<String>) {
         self.license_token = license_token.into();
     }
 
     /// Enables or disables volume normalization.
+    #[inline]
     pub fn set_normalization(&mut self, normalization: bool) {
         self.normalization = normalization;
     }
@@ -1457,35 +1466,41 @@ impl Player {
     ///
     /// Note: Actual quality may be lower if track is not
     /// available in requested quality.
+    #[inline]
     pub fn set_audio_quality(&mut self, quality: AudioQuality) {
         self.audio_quality = quality;
     }
 
     /// Returns whether volume normalization is enabled.
     #[must_use]
+    #[inline]
     pub fn normalization(&self) -> bool {
         self.normalization
     }
 
     /// Returns current license token.
     #[must_use]
+    #[inline]
     pub fn license_token(&self) -> &str {
         &self.license_token
     }
 
     /// Returns current preferred audio quality setting.
     #[must_use]
+    #[inline]
     pub fn audio_quality(&self) -> AudioQuality {
         self.audio_quality
     }
 
     /// Returns current normalization target gain.
     #[must_use]
+    #[inline]
     pub fn gain_target_db(&self) -> i8 {
         self.gain_target_db
     }
 
     /// Sets the media content URL.
+    #[inline]
     pub fn set_media_url(&mut self, url: Url) {
         self.media_url = url;
     }
@@ -1507,6 +1522,7 @@ impl Player {
     /// assert!(!player.is_started());
     /// ```
     #[must_use]
+    #[inline]
     pub fn is_started(&self) -> bool {
         self.sink.is_some()
     }

src/protocol/codec.rs

@@ -83,6 +83,7 @@ impl Codec {
 /// * "flac"
 /// * "mp3"
 impl fmt::Display for Codec {
+    #[inline]
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         match self {
             Codec::AAC => write!(f, "aac"),

src/protocol/connect/channel.rs

@@ -648,6 +648,7 @@ impl FromStr for Channel {
 /// assert_eq!(unspec.to_string(), "-1");
 /// ```
 impl fmt::Display for UserId {
+    #[inline]
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match self {
             Self::Id(id) => write!(f, "{id}"),
@@ -714,6 +715,7 @@ impl FromStr for UserId {
 /// assert!(matches!(user, UserId::Id(_)));
 /// ```
 impl From<NonZeroU64> for UserId {
+    #[inline]
     fn from(id: NonZeroU64) -> Self {
         Self::Id(id)
     }

src/protocol/connect/contents.rs

@@ -943,6 +943,7 @@ pub enum Status {
 /// println!("Command completed with status: {}", Status::OK);
 /// ```
 impl fmt::Display for Status {
+    #[inline]
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match self {
             Status::OK => write!(f, "Ok"),
@@ -1386,6 +1387,7 @@ impl Percentage {
     /// assert_eq!(p.as_percent_f32(), 75.0);
     /// ```
     #[must_use]
+    #[inline]
     pub const fn from_ratio_f32(ratio: f32) -> Self {
         Self(ratio as f64)
     }
@@ -1406,6 +1408,7 @@ impl Percentage {
     /// assert_eq!(p.as_percent_f64(), 50.0);
     /// ```
     #[must_use]
+    #[inline]
     pub const fn from_ratio_f64(ratio: f64) -> Self {
         Self(ratio)
     }
@@ -1426,6 +1429,7 @@ impl Percentage {
     /// assert_eq!(p.as_ratio_f32(), 0.75);
     /// ```
     #[must_use]
+    #[inline]
     pub const fn from_percent_f32(percent: f32) -> Self {
         Self(percent as f64 / 100.0)
     }
@@ -1446,6 +1450,7 @@ impl Percentage {
     /// assert_eq!(p.as_ratio_f64(), 0.75);
     /// ```
     #[must_use]
+    #[inline]
     pub const fn from_percent_f64(percent: f64) -> Self {
         Self(percent / 100.0)
     }
@@ -1478,6 +1483,7 @@ impl Percentage {
     /// assert_eq!(RATIO, 0.333);
     /// ```
     #[must_use]
+    #[inline]
     pub const fn as_ratio_f64(&self) -> f64 {
         self.0
     }
@@ -1510,6 +1516,7 @@ impl Percentage {
     /// assert_eq!(PERCENT, 33.3);
     /// ```
     #[must_use]
+    #[inline]
     pub const fn as_percent_f64(&self) -> f64 {
         self.0 * 100.0
     }
@@ -2420,6 +2427,7 @@ pub enum DeviceType {
 /// assert_eq!(DeviceType::Unknown.to_string(), "unknown");
 /// ```
 impl fmt::Display for DeviceType {
+    #[inline]
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match self {
             DeviceType::Desktop => write!(f, "desktop"),

src/protocol/connect/messages.rs

@@ -418,6 +418,7 @@ enum Stanza {
 /// assert_eq!(Stanza::Send.to_string(), "Send");
 /// ```
 impl fmt::Display for Stanza {
+    #[inline]
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         write!(f, "{self:?}")
     }

src/protocol/connect/stream.rs

@@ -383,6 +383,7 @@ impl Ident {
 /// println!("{contents}");
 /// ```
 impl fmt::Display for Contents {
+    #[inline]
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         write!(f, "{} {}", self.action, self.value.track_id)
     }
@@ -399,6 +400,7 @@ impl fmt::Display for Contents {
 /// assert_eq!(Action::Play.to_string(), "PLAY");
 /// ```
 impl fmt::Display for Action {
+    #[inline]
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match self {
             Self::Play => write!(f, "{}", Self::PLAY),
@@ -445,6 +447,7 @@ impl FromStr for Action {
 /// assert_eq!(Ident::Limitation.to_string(), "LIMITATION");
 /// ```
 impl fmt::Display for Ident {
+    #[inline]
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match self {
             Self::Limitation => write!(f, "{}", Self::LIMITATION),

src/protocol/gateway/list_data/episodes.rs

@@ -65,6 +65,7 @@ pub struct EpisodeData(pub ListData);
 impl Deref for EpisodeData {
     type Target = ListData;
 
+    #[inline]
     fn deref(&self) -> &Self::Target {
         &self.0
     }

src/protocol/gateway/list_data/livestream.rs

@@ -84,6 +84,7 @@ pub struct LivestreamData(pub ListData);
 impl Deref for LivestreamData {
     type Target = ListData;
 
+    #[inline]
     fn deref(&self) -> &Self::Target {
         &self.0
     }