Accept path as crate rename as well

tests-build/tests/fail/macros_invalid_input.rs

@@ -36,13 +36,10 @@ async fn test_worker_threads_not_int() {}
 async fn test_worker_threads_and_current_thread() {}
 
 #[tokio::test(crate = 456)]
-async fn test_crate_not_ident_int() {}
+async fn test_crate_not_path_int() {}
 
 #[tokio::test(crate = "456")]
-async fn test_crate_not_ident_invalid() {}
-
-#[tokio::test(crate = "abc::edf")]
-async fn test_crate_not_ident_path() {}
+async fn test_crate_not_path_invalid() {}
 
 #[tokio::test]
 #[test]

tests-build/tests/fail/macros_invalid_input.stderr

@@ -64,34 +64,28 @@ error: The `worker_threads` option requires the `multi_thread` runtime flavor. U
 35 | #[tokio::test(flavor = "current_thread", worker_threads = 4)]
    |                                                           ^
 
-error: Failed to parse value of `crate` as ident.
+error: Failed to parse value of `crate` as path.
   --> $DIR/macros_invalid_input.rs:38:23
    |
 38 | #[tokio::test(crate = 456)]
    |                       ^^^
 
-error: Failed to parse value of `crate` as ident: "456"
+error: Failed to parse value of `crate` as path: "456"
   --> $DIR/macros_invalid_input.rs:41:23
    |
 41 | #[tokio::test(crate = "456")]
    |                       ^^^^^
 
-error: Failed to parse value of `crate` as ident: "abc::edf"
-  --> $DIR/macros_invalid_input.rs:44:23
-   |
-44 | #[tokio::test(crate = "abc::edf")]
-   |                       ^^^^^^^^^^
-
 error: second test attribute is supplied
-  --> $DIR/macros_invalid_input.rs:48:1
+  --> $DIR/macros_invalid_input.rs:45:1
    |
-48 | #[test]
+45 | #[test]
    | ^^^^^^^
 
 error: duplicated attribute
-  --> $DIR/macros_invalid_input.rs:48:1
+  --> $DIR/macros_invalid_input.rs:45:1
    |
-48 | #[test]
+45 | #[test]
    | ^^^^^^^
    |
 note: the lint level is defined here

tests-build/tests/fail/macros_type_mismatch.stderr

@@ -1,47 +1,51 @@
 error[E0308]: mismatched types
- --> $DIR/macros_type_mismatch.rs:5:5
+ --> $DIR/macros_type_mismatch.rs:3:1
   |
+3 | #[tokio::main]
+  | ^^^^^^^^^^^^^^ expected `()`, found enum `Result`
 4 | async fn missing_semicolon_or_return_type() {
   |                                             - help: a return type might be missing here: `-> _`
-5 |     Ok(())
-  |     ^^^^^^ expected `()`, found enum `Result`
   |
   = note: expected unit type `()`
                   found enum `Result<(), _>`
+  = note: this error originates in the attribute macro `tokio::main` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error[E0308]: mismatched types
-  --> $DIR/macros_type_mismatch.rs:10:5
-   |
-9  | async fn missing_return_type() {
-   |                                - help: a return type might be missing here: `-> _`
-10 |     return Ok(());
-   |     ^^^^^^^^^^^^^^ expected `()`, found enum `Result`
-   |
-   = note: expected unit type `()`
-                   found enum `Result<(), _>`
+ --> $DIR/macros_type_mismatch.rs:8:1
+  |
+8 | #[tokio::main]
+  | ^^^^^^^^^^^^^^ expected `()`, found enum `Result`
+9 | async fn missing_return_type() {
+  |                                - help: a return type might be missing here: `-> _`
+  |
+  = note: expected unit type `()`
+                  found enum `Result<(), _>`
+  = note: this error originates in the attribute macro `tokio::main` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error[E0308]: mismatched types
-  --> $DIR/macros_type_mismatch.rs:23:5
+  --> $DIR/macros_type_mismatch.rs:13:1
    |
+13 | #[tokio::main]
+   | ^^^^^^^^^^^^^^ expected enum `Result`, found `()`
 14 | async fn extra_semicolon() -> Result<(), ()> {
    |                               -------------- expected `Result<(), ()>` because of return type
-...
-23 |     Ok(());
-   |     ^^^^^^^ expected enum `Result`, found `()`
    |
    = note:   expected enum `Result<(), ()>`
            found unit type `()`
-help: try adding an expression at the end of the block
-   |
-23 ~     Ok(());;
-24 +     Ok(())
+   = note: this error originates in the attribute macro `tokio::main` (in Nightly builds, run with -Z macro-backtrace for more info)
+help: try wrapping the expression in a variant of `Result`
    |
+13 | Ok(#[tokio::main])
+   | +++              +
+13 | Err(#[tokio::main])
+   | ++++              +
 
 error[E0308]: mismatched types
-  --> $DIR/macros_type_mismatch.rs:32:5
+  --> $DIR/macros_type_mismatch.rs:29:1
    |
+29 | #[tokio::main]
+   | ^^^^^^^^^^^^^^ expected `()`, found integer
 30 | async fn issue_4635() {
    |                       - help: try adding a return type: `-> i32`
-31 |     return 1;
-32 |     ;
-   |     ^ expected `()`, found integer
+   |
+   = note: this error originates in the attribute macro `tokio::main` (in Nightly builds, run with -Z macro-backtrace for more info)

tokio-macros/src/entry.rs

@@ -1,7 +1,7 @@
 use proc_macro::TokenStream;
-use proc_macro2::{Ident, Span};
+use proc_macro2::Span;
 use quote::{quote, quote_spanned, ToTokens};
-use syn::parse::Parser;
+use syn::{parse::Parser, Ident, Path};
 
 // syn::AttributeArgs does not implement syn::Parse
 type AttributeArgs = syn::punctuated::Punctuated<syn::NestedMeta, syn::Token![,]>;
@@ -29,7 +29,7 @@ struct FinalConfig {
     flavor: RuntimeFlavor,
     worker_threads: Option<usize>,
     start_paused: Option<bool>,
-    crate_name: Option<String>,
+    crate_name: Option<Path>,
 }
 
 /// Config used in case of the attribute not being able to build a valid config
@@ -47,7 +47,7 @@ struct Configuration {
     worker_threads: Option<(usize, Span)>,
     start_paused: Option<(bool, Span)>,
     is_test: bool,
-    crate_name: Option<String>,
+    crate_name: Option<Path>,
 }
 
 impl Configuration {
@@ -112,8 +112,8 @@ impl Configuration {
         if self.crate_name.is_some() {
             return Err(syn::Error::new(span, "`crate` set multiple times."));
         }
-        let name_ident = parse_ident(name, span, "crate")?;
-        self.crate_name = Some(name_ident.to_string());
+        let name_path = parse_path(name, span, "crate")?;
+        self.crate_name = Some(name_path);
         Ok(())
     }
 
@@ -199,23 +199,22 @@ fn parse_string(int: syn::Lit, span: Span, field: &str) -> Result<String, syn::E
     }
 }
 
-fn parse_ident(lit: syn::Lit, span: Span, field: &str) -> Result<Ident, syn::Error> {
+fn parse_path(lit: syn::Lit, span: Span, field: &str) -> Result<Path, syn::Error> {
     match lit {
         syn::Lit::Str(s) => {
             let err = syn::Error::new(
                 span,
                 format!(
-                    "Failed to parse value of `{}` as ident: \"{}\"",
+                    "Failed to parse value of `{}` as path: \"{}\"",
                     field,
                     s.value()
                 ),
             );
-            let path = s.parse::<syn::Path>().map_err(|_| err.clone())?;
-            path.get_ident().cloned().ok_or(err)
+            s.parse::<syn::Path>().map_err(|_| err.clone())
         }
         _ => Err(syn::Error::new(
             span,
-            format!("Failed to parse value of `{}` as ident.", field),
+            format!("Failed to parse value of `{}` as path.", field),
         )),
     }
 }
@@ -354,16 +353,17 @@ fn parse_knobs(mut input: syn::ItemFn, is_test: bool, config: FinalConfig) -> To
         (start, end)
     };
 
-    let crate_name = config.crate_name.as_deref().unwrap_or("tokio");
-
-    let crate_ident = Ident::new(crate_name, last_stmt_start_span);
+    let crate_path = config
+        .crate_name
+        .map(ToTokens::into_token_stream)
+        .unwrap_or_else(|| Ident::new("tokio", last_stmt_start_span).into_token_stream());
 
     let mut rt = match config.flavor {
         RuntimeFlavor::CurrentThread => quote_spanned! {last_stmt_start_span=>
-            #crate_ident::runtime::Builder::new_current_thread()
+            #crate_path::runtime::Builder::new_current_thread()
         },
         RuntimeFlavor::Threaded => quote_spanned! {last_stmt_start_span=>
-            #crate_ident::runtime::Builder::new_multi_thread()
+            #crate_path::runtime::Builder::new_multi_thread()
         },
     };
     if let Some(v) = config.worker_threads {
@@ -414,7 +414,7 @@ fn parse_knobs(mut input: syn::ItemFn, is_test: bool, config: FinalConfig) -> To
         };
         quote! {
             let body = async #body;
-            #crate_ident::pin!(body);
+            #crate_path::pin!(body);
             let body: ::std::pin::Pin<&mut dyn ::std::future::Future<Output = #output_type>> = body;
         }
     } else {

tokio/tests/macros_rename_test.rs

@@ -5,6 +5,10 @@ use std as tokio;
 
 use ::tokio as tokio1;
 
+mod test {
+    pub use ::tokio;
+}
+
 async fn compute() -> usize {
     let join = tokio1::spawn(async { 1 });
     join.await.unwrap()
@@ -24,3 +28,8 @@ fn crate_rename_main() {
 async fn crate_rename_test() {
     assert_eq!(1, compute().await);
 }
+
+#[test::tokio::test(crate = "test::tokio")]
+async fn crate_path_test() {
+    assert_eq!(1, compute().await);
+}