add more tracing to transforms and parsing (vercel/turborepo#8346)

### Description

allows to investigate parsing slowness

### Testing Instructions

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  Give a quick description of steps to test your changes.
-->

crates/turbopack-ecmascript-plugins/Cargo.toml

@@ -28,6 +28,7 @@ indexmap = { workspace = true }
 lightningcss = { workspace = true }
 serde = { workspace = true }
 serde_json = { workspace = true }
+tracing = { workspace = true }
 
 turbo-tasks = { workspace = true }
 turbo-tasks-fs = { workspace = true }

crates/turbopack-ecmascript-plugins/src/transform/directives/client.rs

@@ -19,6 +19,7 @@ impl ClientDirectiveTransformer {
 
 #[async_trait]
 impl CustomTransformer for ClientDirectiveTransformer {
+    #[tracing::instrument(level = tracing::Level::TRACE, name = "client_directive", skip_all)]
     async fn transform(&self, program: &mut Program, ctx: &TransformContext<'_>) -> Result<()> {
         if is_client_module(program) {
             let transition_name = &*self.transition_name.await?;

crates/turbopack-ecmascript-plugins/src/transform/directives/server.rs

@@ -28,6 +28,7 @@ impl ServerDirectiveTransformer {
 
 #[async_trait]
 impl CustomTransformer for ServerDirectiveTransformer {
+    #[tracing::instrument(level = tracing::Level::TRACE, name = "server_directive", skip_all)]
     async fn transform(&self, program: &mut Program, ctx: &TransformContext<'_>) -> Result<()> {
         if is_server_module(program) {
             let stmt = quote!(

crates/turbopack-ecmascript-plugins/src/transform/emotion.rs

@@ -94,6 +94,7 @@ impl EmotionTransformer {
 
 #[async_trait]
 impl CustomTransformer for EmotionTransformer {
+    #[tracing::instrument(level = tracing::Level::TRACE, name = "emotion", skip_all)]
     async fn transform(&self, program: &mut Program, ctx: &TransformContext<'_>) -> Result<()> {
         #[cfg(feature = "transform_emotion")]
         {

crates/turbopack-ecmascript-plugins/src/transform/modularize_imports.rs

@@ -52,6 +52,7 @@ impl ModularizeImportsTransformer {
 
 #[async_trait]
 impl CustomTransformer for ModularizeImportsTransformer {
+    #[tracing::instrument(level = tracing::Level::TRACE, name = "modularize_imports", skip_all)]
     async fn transform(&self, program: &mut Program, _ctx: &TransformContext<'_>) -> Result<()> {
         let p = std::mem::replace(program, Program::Module(Module::dummy()));
         *program = p.fold_with(&mut modularize_imports(Config {

crates/turbopack-ecmascript-plugins/src/transform/relay.rs

@@ -55,6 +55,7 @@ impl RelayTransformer {
 
 #[async_trait]
 impl CustomTransformer for RelayTransformer {
+    #[tracing::instrument(level = tracing::Level::TRACE, name = "relay", skip_all)]
     async fn transform(&self, program: &mut Program, ctx: &TransformContext<'_>) -> Result<()> {
         // If user supplied artifact_directory, it should be resolvable already.
         // Otherwise, supply default relative path (./__generated__)

crates/turbopack-ecmascript-plugins/src/transform/styled_components.rs

@@ -92,6 +92,7 @@ impl StyledComponentsTransformer {
 
 #[async_trait]
 impl CustomTransformer for StyledComponentsTransformer {
+    #[tracing::instrument(level = tracing::Level::TRACE, name = "styled_components", skip_all)]
     async fn transform(&self, program: &mut Program, ctx: &TransformContext<'_>) -> Result<()> {
         program.visit_mut_with(&mut styled_components::styled_components(
             FileName::Real(PathBuf::from(ctx.file_path_str)),

crates/turbopack-ecmascript-plugins/src/transform/styled_jsx.rs

@@ -31,6 +31,7 @@ impl StyledJsxTransformer {
 
 #[async_trait]
 impl CustomTransformer for StyledJsxTransformer {
+    #[tracing::instrument(level = tracing::Level::TRACE, name = "styled_jsx", skip_all)]
     async fn transform(&self, program: &mut Program, ctx: &TransformContext<'_>) -> Result<()> {
         let p = std::mem::replace(program, Program::Module(Module::dummy()));
         *program = p.fold_with(&mut styled_jsx::visitor::styled_jsx(

crates/turbopack-ecmascript-plugins/src/transform/swc_ecma_transform_plugins.rs

@@ -114,6 +114,7 @@ impl SwcEcmaTransformPluginsTransformer {
 #[async_trait]
 impl CustomTransformer for SwcEcmaTransformPluginsTransformer {
     #[cfg_attr(not(feature = "swc_ecma_transform_plugin"), allow(unused))]
+    #[tracing::instrument(level = tracing::Level::TRACE, name = "swc_ecma_transform_plugin", skip_all)]
     async fn transform(&self, program: &mut Program, ctx: &TransformContext<'_>) -> Result<()> {
         #[cfg(feature = "swc_ecma_transform_plugin")]
         {

crates/turbopack-ecmascript/src/parse.rs

@@ -322,7 +322,9 @@ async fn parse_content(
                 );
 
                 let mut parser = Parser::new_from(lexer);
+                let span = tracing::trace_span!("swc_parse").entered();
                 let program_result = parser.parse_program();
+                drop(span);
 
                 let mut has_errors = vec![];
                 for e in parser.take_errors() {
@@ -360,11 +362,16 @@ async fn parse_content(
                 EcmascriptModuleAssetType::Typescript { .. }
                     | EcmascriptModuleAssetType::TypescriptDeclaration
             );
+            let span = tracing::trace_span!("swc_resolver").entered();
+
             parsed_program.visit_mut_with(&mut resolver(
                 unresolved_mark,
                 top_level_mark,
                 is_typescript,
             ));
+            drop(span);
+
+            let span = tracing::trace_span!("swc_lint").entered();
 
             let lint_config = LintConfig::default();
             let rules = swc_core::ecma::lints::rules::all(LintParams {
@@ -377,6 +384,7 @@ async fn parse_content(
             });
             parsed_program =
                 parsed_program.fold_with(&mut swc_core::ecma::lints::rules::lint_to_fold(rules));
+            drop(span);
 
             let transform_context = TransformContext {
                 comments: &comments,
@@ -388,11 +396,17 @@ async fn parse_content(
                 file_name_hash: file_path_hash,
                 file_path: fs_path_vc,
             };
-            for transform in transforms.iter() {
-                transform
-                    .apply(&mut parsed_program, &transform_context)
-                    .await?;
+            let span = tracing::trace_span!("transforms");
+            async {
+                for transform in transforms.iter() {
+                    transform
+                        .apply(&mut parsed_program, &transform_context)
+                        .await?;
+                }
+                anyhow::Ok(())
             }
+            .instrument(span)
+            .await?;
 
             if parser_handler.has_errors() {
                 let messages = if let Some(error) = emitter.emitted_issues.last() {