Use strum to iterate through enum variants and get their names (#35933)

`strum` allows us to avoid manually listing enum variant names and also
to get their names as static strings. We cannot use this for all cases
due to https://github.com/Peternator7/strum/issues/152, but we can
still use it to remove a lot of code.

Signed-off-by: Martin Robinson <mrobinson@igalia.com>

components/shared/compositing/Cargo.toml

@@ -22,6 +22,7 @@ log = { workspace = true }
 pixels = { path = '../../pixels' }
 script_traits = { workspace = true }
 servo_url = { path = "../../url" }
+strum_macros = { workspace = true }
 style_traits = { workspace = true }
 webrender_api = { workspace = true }
 webrender_traits = { workspace = true }

components/shared/compositing/constellation_msg.rs

@@ -14,9 +14,11 @@ use embedder_traits::{
 use ipc_channel::ipc::IpcSender;
 use script_traits::{AnimationTickType, LogEntry, WindowSizeData, WindowSizeType};
 use servo_url::ServoUrl;
+use strum_macros::IntoStaticStr;
 use webrender_traits::CompositorHitTestResult;
 
 /// Messages to the constellation.
+#[derive(IntoStaticStr)]
 pub enum ConstellationMsg {
     /// Exit the constellation.
     Exit,
@@ -77,41 +79,7 @@ pub enum ConstellationMsg {
 
 impl fmt::Debug for ConstellationMsg {
     fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
-        write!(formatter, "ConstellationMsg::{}", self.variant_name())
-    }
-}
-
-impl ConstellationMsg {
-    /// Return the variant name, for error logging that happens after the message is consumed.
-    pub fn variant_name(&self) -> &'static str {
-        use self::ConstellationMsg::*;
-        match *self {
-            Exit => "Exit",
-            GetBrowsingContext(..) => "GetBrowsingContext",
-            GetPipeline(..) => "GetPipeline",
-            GetFocusTopLevelBrowsingContext(..) => "GetFocusTopLevelBrowsingContext",
-            IsReadyToSaveImage(..) => "IsReadyToSaveImage",
-            AllowNavigationResponse(..) => "AllowNavigationResponse",
-            LoadUrl(..) => "LoadUrl",
-            TraverseHistory(..) => "TraverseHistory",
-            WindowSize(..) => "WindowSize",
-            ThemeChange(..) => "ThemeChange",
-            TickAnimation(..) => "TickAnimation",
-            WebDriverCommand(..) => "WebDriverCommand",
-            Reload(..) => "Reload",
-            LogEntry(..) => "LogEntry",
-            NewWebView(..) => "NewWebView",
-            CloseWebView(..) => "CloseWebView",
-            FocusWebView(..) => "FocusWebView",
-            BlurWebView => "BlurWebView",
-            SendError(..) => "SendError",
-            ForwardInputEvent(..) => "ForwardEvent",
-            SetCursor(..) => "SetCursor",
-            ToggleProfiler(..) => "EnableProfiler",
-            ExitFullScreen(..) => "ExitFullScreen",
-            MediaSessionAction(..) => "MediaSessionAction",
-            SetWebViewThrottled(..) => "SetWebViewThrottled",
-            ClearCache => "ClearCache",
-        }
+        let variant_string: &'static str = self.into();
+        write!(formatter, "ConstellationMsg::{variant_string}")
     }
 }

components/shared/compositing/lib.rs

@@ -18,6 +18,7 @@ use ipc_channel::ipc::IpcSender;
 use log::warn;
 use pixels::Image;
 use script_traits::{AnimationState, ScriptThreadMessage, TouchEventResult};
+use strum_macros::IntoStaticStr;
 use style_traits::CSSPixel;
 use webrender_api::DocumentId;
 use webrender_traits::{CrossProcessCompositorApi, CrossProcessCompositorMessage};
@@ -57,6 +58,7 @@ impl CompositorReceiver {
 }
 
 /// Messages from (or via) the constellation thread to the compositor.
+#[derive(IntoStaticStr)]
 pub enum CompositorMsg {
     /// Alerts the compositor that the given pipeline has changed whether it is running animations.
     ChangeRunningAnimationsState(WebViewId, PipelineId, AnimationState),
@@ -112,24 +114,8 @@ pub struct CompositionPipeline {
 }
 
 impl Debug for CompositorMsg {
-    fn fmt(&self, f: &mut Formatter) -> Result<(), Error> {
-        match *self {
-            CompositorMsg::ChangeRunningAnimationsState(_, _, state) => {
-                write!(f, "ChangeRunningAnimationsState({:?})", state)
-            },
-            CompositorMsg::CreateOrUpdateWebView(..) => write!(f, "CreateOrUpdateWebView"),
-            CompositorMsg::RemoveWebView(..) => write!(f, "RemoveWebView"),
-            CompositorMsg::TouchEventProcessed(..) => write!(f, "TouchEventProcessed"),
-            CompositorMsg::CreatePng(..) => write!(f, "CreatePng"),
-            CompositorMsg::IsReadyToSaveImageReply(..) => write!(f, "IsReadyToSaveImageReply"),
-            CompositorMsg::SetThrottled(..) => write!(f, "SetThrottled"),
-            CompositorMsg::PipelineExited(..) => write!(f, "PipelineExited"),
-            CompositorMsg::NewWebRenderFrameReady(..) => write!(f, "NewWebRenderFrameReady"),
-            CompositorMsg::PendingPaintMetric(..) => write!(f, "PendingPaintMetric"),
-            CompositorMsg::LoadComplete(..) => write!(f, "LoadComplete"),
-            CompositorMsg::WebDriverMouseButtonEvent(..) => write!(f, "WebDriverMouseButtonEvent"),
-            CompositorMsg::WebDriverMouseMoveEvent(..) => write!(f, "WebDriverMouseMoveEvent"),
-            CompositorMsg::CrossProcess(..) => write!(f, "CrossProcess"),
-        }
+    fn fmt(&self, formatter: &mut Formatter) -> Result<(), Error> {
+        let string: &'static str = self.into();
+        write!(formatter, "{string}")
     }
 }

components/shared/embedder/Cargo.toml

@@ -32,6 +32,7 @@ num-traits = { workspace = true }
 pixels = { path = "../../pixels" }
 serde = { workspace = true }
 servo_url = { path = "../../url" }
+strum_macros = { workspace = true }
 style_traits = { workspace = true }
 url = { workspace = true }
 webdriver = { workspace = true }

components/shared/embedder/lib.rs

@@ -19,6 +19,7 @@ use malloc_size_of_derive::MallocSizeOf;
 use num_derive::FromPrimitive;
 use serde::{Deserialize, Serialize};
 use servo_url::ServoUrl;
+use strum_macros::IntoStaticStr;
 use url::Url;
 use webrender_api::units::{DeviceIntPoint, DeviceIntRect, DeviceIntSize};
 
@@ -213,7 +214,7 @@ pub enum AllowOrDeny {
     Deny,
 }
 
-#[derive(Deserialize, Serialize)]
+#[derive(Deserialize, IntoStaticStr, Serialize)]
 pub enum EmbedderMsg {
     /// A status message to be displayed by the browser chrome.
     Status(WebViewId, Option<String>),
@@ -322,49 +323,9 @@ pub enum EmbedderMsg {
 }
 
 impl Debug for EmbedderMsg {
-    fn fmt(&self, f: &mut Formatter) -> Result<(), Error> {
-        match *self {
-            EmbedderMsg::Status(..) => write!(f, "Status"),
-            EmbedderMsg::ChangePageTitle(..) => write!(f, "ChangePageTitle"),
-            EmbedderMsg::MoveTo(..) => write!(f, "MoveTo"),
-            EmbedderMsg::ResizeTo(..) => write!(f, "ResizeTo"),
-            EmbedderMsg::ShowSimpleDialog(..) => write!(f, "ShowSimpleDialog"),
-            EmbedderMsg::RequestAuthentication(..) => write!(f, "RequestAuthentication"),
-            EmbedderMsg::AllowUnload(..) => write!(f, "AllowUnload"),
-            EmbedderMsg::AllowNavigationRequest(..) => write!(f, "AllowNavigationRequest"),
-            EmbedderMsg::Keyboard(..) => write!(f, "Keyboard"),
-            EmbedderMsg::ClearClipboard(..) => write!(f, "ClearClipboard"),
-            EmbedderMsg::GetClipboardText(..) => write!(f, "GetClipboardText"),
-            EmbedderMsg::SetClipboardText(..) => write!(f, "SetClipboardText"),
-            EmbedderMsg::SetCursor(..) => write!(f, "SetCursor"),
-            EmbedderMsg::NewFavicon(..) => write!(f, "NewFavicon"),
-            EmbedderMsg::HistoryChanged(..) => write!(f, "HistoryChanged"),
-            EmbedderMsg::NotifyFullscreenStateChanged(..) => {
-                write!(f, "NotifyFullscreenStateChanged")
-            },
-            EmbedderMsg::NotifyLoadStatusChanged(_, status) => {
-                write!(f, "NotifyLoadStatusChanged({status:?})")
-            },
-            EmbedderMsg::WebResourceRequested(..) => write!(f, "WebResourceRequested"),
-            EmbedderMsg::Panic(..) => write!(f, "Panic"),
-            EmbedderMsg::GetSelectedBluetoothDevice(..) => write!(f, "GetSelectedBluetoothDevice"),
-            EmbedderMsg::SelectFiles(..) => write!(f, "SelectFiles"),
-            EmbedderMsg::PromptPermission(..) => write!(f, "PromptPermission"),
-            EmbedderMsg::ShowIME(..) => write!(f, "ShowIME"),
-            EmbedderMsg::HideIME(..) => write!(f, "HideIME"),
-            EmbedderMsg::AllowOpeningWebView(..) => write!(f, "AllowOpeningWebView"),
-            EmbedderMsg::WebViewClosed(..) => write!(f, "WebViewClosed"),
-            EmbedderMsg::WebViewFocused(..) => write!(f, "WebViewFocused"),
-            EmbedderMsg::WebViewBlurred => write!(f, "WebViewBlurred"),
-            EmbedderMsg::ReportProfile(..) => write!(f, "ReportProfile"),
-            EmbedderMsg::MediaSessionEvent(..) => write!(f, "MediaSessionEvent"),
-            EmbedderMsg::OnDevtoolsStarted(..) => write!(f, "OnDevtoolsStarted"),
-            EmbedderMsg::RequestDevtoolsConnection(..) => write!(f, "RequestDevtoolsConnection"),
-            EmbedderMsg::ShowContextMenu(..) => write!(f, "ShowContextMenu"),
-            EmbedderMsg::PlayGamepadHapticEffect(..) => write!(f, "PlayGamepadHapticEffect"),
-            EmbedderMsg::StopGamepadHapticEffect(..) => write!(f, "StopGamepadHapticEffect"),
-            EmbedderMsg::ShutdownComplete => write!(f, "ShutdownComplete"),
-        }
+    fn fmt(&self, formatter: &mut Formatter) -> Result<(), Error> {
+        let string: &'static str = self.into();
+        write!(formatter, "{string}")
     }
 }
 

components/shared/profile/Cargo.toml

@@ -22,5 +22,6 @@ log = { workspace = true }
 serde = { workspace = true }
 servo_config = { path = "../../config" }
 signpost = { git = "https://github.com/pcwalton/signpost.git" }
+strum_macros = { workspace = true }
 time = { workspace = true }
 tracing = { workspace = true, optional = true }

components/shared/profile/time.rs

@@ -7,6 +7,7 @@ use ipc_channel::ipc::IpcSender;
 use log::warn;
 use serde::{Deserialize, Serialize};
 use servo_config::opts;
+use strum_macros::IntoStaticStr;
 use time::Duration;
 
 #[derive(Clone, Debug, Deserialize, Eq, Ord, PartialEq, PartialOrd, Serialize)]
@@ -57,7 +58,9 @@ pub enum ProfilerMsg {
 
 /// Usage sites of variants marked “Rust tracing only” are not visible to rust-analyzer.
 #[repr(u32)]
-#[derive(Clone, Copy, Debug, Deserialize, Eq, Hash, Ord, PartialEq, PartialOrd, Serialize)]
+#[derive(
+    Clone, Copy, Debug, Deserialize, Eq, Hash, IntoStaticStr, Ord, PartialEq, PartialOrd, Serialize,
+)]
 pub enum ProfilerCategory {
     /// The compositor is rasterising or presenting.
     ///

components/shared/script/Cargo.toml

@@ -39,6 +39,7 @@ net_traits = { workspace = true }
 pixels = { path = "../../pixels" }
 profile_traits = { workspace = true }
 serde = { workspace = true }
+strum_macros = { workspace = true }
 stylo_atoms = { workspace = true }
 servo_url = { path = "../../url" }
 style_traits = { workspace = true }

components/shared/script/lib.rs

@@ -50,6 +50,7 @@ use pixels::PixelFormat;
 use profile_traits::{mem, time as profile_time};
 use serde::{Deserialize, Deserializer, Serialize, Serializer};
 use servo_url::{ImmutableOrigin, ServoUrl};
+use strum_macros::IntoStaticStr;
 use style_traits::{CSSPixel, SpeculativePainter};
 use stylo_atoms::Atom;
 #[cfg(feature = "webgpu")]
@@ -288,7 +289,7 @@ pub enum UpdatePipelineIdReason {
 
 /// Messages sent to the `ScriptThread` event loop from the `Constellation`, `Compositor`, and (for
 /// now) `Layout`.
-#[derive(Deserialize, Serialize)]
+#[derive(Deserialize, IntoStaticStr, Serialize)]
 pub enum ScriptThreadMessage {
     /// Takes the associated window proxy out of "delaying-load-events-mode",
     /// used if a scheduled navigated was refused by the embedder.
@@ -408,44 +409,8 @@ pub enum ScriptThreadMessage {
 
 impl fmt::Debug for ScriptThreadMessage {
     fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
-        use self::ScriptThreadMessage::*;
-        let variant = match *self {
-            StopDelayingLoadEventsMode(..) => "StopDelayingLoadsEventMode",
-            AttachLayout(..) => "AttachLayout",
-            Resize(..) => "Resize",
-            ThemeChange(..) => "ThemeChange",
-            ResizeInactive(..) => "ResizeInactive",
-            UnloadDocument(..) => "UnloadDocument",
-            ExitPipeline(..) => "ExitPipeline",
-            ExitScriptThread => "ExitScriptThread",
-            SendInputEvent(..) => "SendInputEvent",
-            Viewport(..) => "Viewport",
-            GetTitle(..) => "GetTitle",
-            SetDocumentActivity(..) => "SetDocumentActivity",
-            SetThrottled(..) => "SetThrottled",
-            SetThrottledInContainingIframe(..) => "SetThrottledInContainingIframe",
-            NavigateIframe(..) => "NavigateIframe",
-            PostMessage { .. } => "PostMessage",
-            UpdatePipelineId(..) => "UpdatePipelineId",
-            UpdateHistoryState(..) => "UpdateHistoryState",
-            RemoveHistoryStates(..) => "RemoveHistoryStates",
-            FocusIFrame(..) => "FocusIFrame",
-            WebDriverScriptCommand(..) => "WebDriverScriptCommand",
-            TickAllAnimations(..) => "TickAllAnimations",
-            WebFontLoaded(..) => "WebFontLoaded",
-            DispatchIFrameLoadEvent { .. } => "DispatchIFrameLoadEvent",
-            DispatchStorageEvent(..) => "DispatchStorageEvent",
-            ReportCSSError(..) => "ReportCSSError",
-            Reload(..) => "Reload",
-            PaintMetric(..) => "PaintMetric",
-            ExitFullScreen(..) => "ExitFullScreen",
-            MediaSessionAction(..) => "MediaSessionAction",
-            #[cfg(feature = "webgpu")]
-            SetWebGPUPort(..) => "SetWebGPUPort",
-            SetScrollStates(..) => "SetScrollStates",
-            SetEpochPaintTime(..) => "SetEpochPaintTime",
-        };
-        write!(formatter, "ConstellationControlMsg::{}", variant)
+        let variant_string: &'static str = self.into();
+        write!(formatter, "ConstellationControlMsg::{variant_string}")
     }
 }
 

components/shared/script/script_msg.rs

@@ -22,6 +22,7 @@ use net_traits::CoreResourceMsg;
 use net_traits::storage_thread::StorageType;
 use serde::{Deserialize, Serialize};
 use servo_url::{ImmutableOrigin, ServoUrl};
+use strum_macros::IntoStaticStr;
 use style_traits::CSSPixel;
 #[cfg(feature = "webgpu")]
 use webgpu::{WebGPU, WebGPUResponse, wgc};
@@ -46,7 +47,7 @@ pub struct IFrameSizeMsg {
 }
 
 /// Messages from the layout to the constellation.
-#[derive(Deserialize, Serialize)]
+#[derive(Deserialize, IntoStaticStr, Serialize)]
 pub enum LayoutMsg {
     /// Requests that the constellation inform the compositor that it needs to record
     /// the time when the frame with the given ID (epoch) is painted.
@@ -55,11 +56,8 @@ pub enum LayoutMsg {
 
 impl fmt::Debug for LayoutMsg {
     fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
-        use self::LayoutMsg::*;
-        let variant = match *self {
-            PendingPaintMetric(..) => "PendingPaintMetric",
-        };
-        write!(formatter, "LayoutMsg::{}", variant)
+        let variant_string: &'static str = self.into();
+        write!(formatter, "LayoutMsg::{variant_string}")
     }
 }
 
@@ -86,7 +84,7 @@ pub enum LogEntry {
 }
 
 /// Messages from the script to the constellation.
-#[derive(Deserialize, Serialize)]
+#[derive(Deserialize, IntoStaticStr, Serialize)]
 pub enum ScriptMsg {
     /// Request to complete the transfer of a set of ports to a router.
     CompleteMessagePortTransfer(MessagePortRouterId, Vec<MessagePortId>),
@@ -252,65 +250,8 @@ pub enum ScriptMsg {
 
 impl fmt::Debug for ScriptMsg {
     fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
-        use self::ScriptMsg::*;
-        let variant = match *self {
-            CompleteMessagePortTransfer(..) => "CompleteMessagePortTransfer",
-            MessagePortTransferResult(..) => "MessagePortTransferResult",
-            NewMessagePortRouter(..) => "NewMessagePortRouter",
-            RemoveMessagePortRouter(..) => "RemoveMessagePortRouter",
-            NewMessagePort(..) => "NewMessagePort",
-            RerouteMessagePort(..) => "RerouteMessagePort",
-            RemoveMessagePort(..) => "RemoveMessagePort",
-            MessagePortShipped(..) => "MessagePortShipped",
-            EntanglePorts(..) => "EntanglePorts",
-            NewBroadcastChannelRouter(..) => "NewBroadcastChannelRouter",
-            RemoveBroadcastChannelRouter(..) => "RemoveBroadcastChannelRouter",
-            RemoveBroadcastChannelNameInRouter(..) => "RemoveBroadcastChannelNameInRouter",
-            NewBroadcastChannelNameInRouter(..) => "NewBroadcastChannelNameInRouter",
-            ScheduleBroadcast(..) => "ScheduleBroadcast",
-            ForwardToEmbedder(..) => "ForwardToEmbedder",
-            BroadcastStorageEvent(..) => "BroadcastStorageEvent",
-            ChangeRunningAnimationsState(..) => "ChangeRunningAnimationsState",
-            CreateCanvasPaintThread(..) => "CreateCanvasPaintThread",
-            Focus => "Focus",
-            GetBrowsingContextInfo(..) => "GetBrowsingContextInfo",
-            GetTopForBrowsingContext(..) => "GetParentBrowsingContext",
-            GetChildBrowsingContextId(..) => "GetChildBrowsingContextId",
-            LoadComplete => "LoadComplete",
-            LoadUrl(..) => "LoadUrl",
-            AbortLoadUrl => "AbortLoadUrl",
-            PostMessage { .. } => "PostMessage",
-            NavigatedToFragment(..) => "NavigatedToFragment",
-            TraverseHistory(..) => "TraverseHistory",
-            PushHistoryState(..) => "PushHistoryState",
-            ReplaceHistoryState(..) => "ReplaceHistoryState",
-            JointSessionHistoryLength(..) => "JointSessionHistoryLength",
-            RemoveIFrame(..) => "RemoveIFrame",
-            SetThrottledComplete(..) => "SetThrottledComplete",
-            ScriptLoadedURLInIFrame(..) => "ScriptLoadedURLInIFrame",
-            ScriptNewIFrame(..) => "ScriptNewIFrame",
-            CreateAuxiliaryWebView(..) => "ScriptNewAuxiliary",
-            ActivateDocument => "ActivateDocument",
-            SetDocumentState(..) => "SetDocumentState",
-            SetLayoutEpoch(..) => "SetLayoutEpoch",
-            SetFinalUrl(..) => "SetFinalUrl",
-            TouchEventProcessed(..) => "TouchEventProcessed",
-            LogEntry(..) => "LogEntry",
-            DiscardDocument => "DiscardDocument",
-            DiscardTopLevelBrowsingContext => "DiscardTopLevelBrowsingContext",
-            PipelineExited => "PipelineExited",
-            ForwardDOMMessage(..) => "ForwardDOMMessage",
-            ScheduleJob(..) => "ScheduleJob",
-            MediaSessionEvent(..) => "MediaSessionEvent",
-            #[cfg(feature = "webgpu")]
-            RequestAdapter(..) => "RequestAdapter",
-            #[cfg(feature = "webgpu")]
-            GetWebGPUChan(..) => "GetWebGPUChan",
-            TitleChanged(..) => "TitleChanged",
-            IFrameSizes(..) => "IFramSizes",
-            ReportMemory(..) => "ReportMemory",
-        };
-        write!(formatter, "ScriptMsg::{}", variant)
+        let variant_string: &'static str = self.into();
+        write!(formatter, "ScriptMsg::{variant_string}")
     }
 }