add tags to turbo tasks (vercel/turborepo#8038)

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### Testing Instructions

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Closes TURBO-2878

crates/turbo-tasks-fetch/src/lib.rs

@@ -46,7 +46,7 @@ pub enum ProxyConfig {
 #[turbo_tasks::value(transparent)]
 pub struct OptionProxyConfig(Option<ProxyConfig>);
 
-#[turbo_tasks::function]
+#[turbo_tasks::function(network)]
 pub async fn fetch(
     url: Vc<RcStr>,
     user_agent: Vc<Option<RcStr>>,

crates/turbo-tasks-fs/src/attach.rs

@@ -121,17 +121,17 @@ impl AttachedFileSystem {
 
 #[turbo_tasks::value_impl]
 impl FileSystem for AttachedFileSystem {
-    #[turbo_tasks::function]
+    #[turbo_tasks::function(fs)]
     fn read(self: Vc<Self>, path: Vc<FileSystemPath>) -> Vc<FileContent> {
         self.get_inner_fs_path(path).read()
     }
 
-    #[turbo_tasks::function]
+    #[turbo_tasks::function(fs)]
     fn read_link(self: Vc<Self>, path: Vc<FileSystemPath>) -> Vc<LinkContent> {
         self.get_inner_fs_path(path).read_link()
     }
 
-    #[turbo_tasks::function]
+    #[turbo_tasks::function(fs)]
     async fn read_dir(self: Vc<Self>, path: Vc<FileSystemPath>) -> Result<Vc<DirectoryContent>> {
         let dir_content = self.get_inner_fs_path(path).read_dir().await?;
         let entries = match &*dir_content {
@@ -157,17 +157,17 @@ impl FileSystem for AttachedFileSystem {
         Ok(DirectoryContent::new(converted_entries))
     }
 
-    #[turbo_tasks::function]
+    #[turbo_tasks::function(fs)]
     fn track(self: Vc<Self>, path: Vc<FileSystemPath>) -> Vc<Completion> {
         self.get_inner_fs_path(path).track()
     }
 
-    #[turbo_tasks::function]
+    #[turbo_tasks::function(fs)]
     fn write(self: Vc<Self>, path: Vc<FileSystemPath>, content: Vc<FileContent>) -> Vc<Completion> {
         self.get_inner_fs_path(path).write(content)
     }
 
-    #[turbo_tasks::function]
+    #[turbo_tasks::function(fs)]
     fn write_link(
         self: Vc<Self>,
         path: Vc<FileSystemPath>,

crates/turbo-tasks-fs/src/lib.rs

@@ -317,7 +317,7 @@ impl Debug for DiskFileSystem {
 
 #[turbo_tasks::value_impl]
 impl FileSystem for DiskFileSystem {
-    #[turbo_tasks::function]
+    #[turbo_tasks::function(fs)]
     async fn read(&self, fs_path: Vc<FileSystemPath>) -> Result<Vc<FileContent>> {
         let full_path = self.to_sys_path(fs_path).await?;
         self.register_invalidator(&full_path)?;
@@ -341,7 +341,7 @@ impl FileSystem for DiskFileSystem {
         Ok(content.cell())
     }
 
-    #[turbo_tasks::function]
+    #[turbo_tasks::function(fs)]
     async fn read_dir(&self, fs_path: Vc<FileSystemPath>) -> Result<Vc<DirectoryContent>> {
         let full_path = self.to_sys_path(fs_path).await?;
         self.register_dir_invalidator(&full_path)?;
@@ -400,7 +400,7 @@ impl FileSystem for DiskFileSystem {
         Ok(DirectoryContent::new(entries))
     }
 
-    #[turbo_tasks::function]
+    #[turbo_tasks::function(fs)]
     async fn read_link(&self, fs_path: Vc<FileSystemPath>) -> Result<Vc<LinkContent>> {
         let full_path = self.to_sys_path(fs_path).await?;
         self.register_invalidator(&full_path)?;
@@ -484,14 +484,14 @@ impl FileSystem for DiskFileSystem {
         .cell())
     }
 
-    #[turbo_tasks::function]
+    #[turbo_tasks::function(fs)]
     async fn track(&self, fs_path: Vc<FileSystemPath>) -> Result<Vc<Completion>> {
         let full_path = self.to_sys_path(fs_path).await?;
         self.register_invalidator(&full_path)?;
         Ok(Completion::new())
     }
 
-    #[turbo_tasks::function]
+    #[turbo_tasks::function(fs)]
     async fn write(
         &self,
         fs_path: Vc<FileSystemPath>,
@@ -605,7 +605,7 @@ impl FileSystem for DiskFileSystem {
         Ok(Completion::new())
     }
 
-    #[turbo_tasks::function]
+    #[turbo_tasks::function(fs)]
     async fn write_link(
         &self,
         fs_path: Vc<FileSystemPath>,
@@ -692,7 +692,7 @@ impl FileSystem for DiskFileSystem {
         Ok(Completion::new())
     }
 
-    #[turbo_tasks::function]
+    #[turbo_tasks::function(fs)]
     async fn metadata(&self, fs_path: Vc<FileSystemPath>) -> Result<Vc<FileMeta>> {
         let full_path = self.to_sys_path(fs_path).await?;
         self.register_invalidator(&full_path)?;

crates/turbo-tasks-fs/src/read_glob.rs

@@ -16,7 +16,7 @@ pub struct ReadGlobResult {
 ///
 /// DETERMINISM: Result is in random order. Either sort result or do not depend
 /// on the order.
-#[turbo_tasks::function]
+#[turbo_tasks::function(fs)]
 pub async fn read_glob(
     directory: Vc<FileSystemPath>,
     glob: Vc<Glob>,
@@ -25,7 +25,7 @@ pub async fn read_glob(
     read_glob_internal("", directory, glob, include_dot_files).await
 }
 
-#[turbo_tasks::function]
+#[turbo_tasks::function(fs)]
 async fn read_glob_inner(
     prefix: RcStr,
     directory: Vc<FileSystemPath>,

crates/turbo-tasks-macros/src/function_macro.rs

@@ -6,6 +6,25 @@ use turbo_tasks_macros_shared::{get_native_function_id_ident, get_native_functio
 
 use crate::func::{DefinitionContext, NativeFn, TurboFn};
 
+/// This macro generates the virtual function that powers turbo tasks.
+/// An annotated task is replaced with a stub function that returns a
+/// lazy completion (Vc), and stamps out the concrete implementation
+/// of the task alongside that the Vc uses to resolve itself.
+///
+/// Functions support being tagged for informational purposes. This
+/// is currently only used in turbo-static for doing static analysis
+/// of tasks.
+///
+/// # Examples
+///
+/// ```rust
+/// use turbo_tasks::{Vc};
+///
+/// #[turbo_tasks::function(fs)]
+/// async fn my_task() -> Vc<usize> {
+///     // access filesystem
+/// }
+/// ```
 pub fn function(_args: TokenStream, input: TokenStream) -> TokenStream {
     let item = parse_macro_input!(input as ItemFn);