macros: add build tests for #[tokio::main] and #[tokio::test] (#1591)

azure-pipelines.yml

@@ -85,6 +85,7 @@ jobs:
         - tokio-executor
         - tokio-net
         - executor-without-current-thread
+        - macros-invalid-input
         - net-no-features
         - net-with-tcp
         - net-with-udp

build-tests/Cargo.toml

@@ -7,6 +7,7 @@ publish = false
 
 [features]
 executor-without-current-thread = ["tokio-executor"]
+macros-invalid-input = ["tokio/rt-full"]
 net-no-features = ["tokio-net"]
 net-with-tcp = ["tokio-net/tcp"]
 net-with-udp = ["tokio-net/udp"]

build-tests/tests/fail/macros_invalid_input.rs

@@ -0,0 +1,28 @@
+use build_tests::tokio;
+
+#[tokio::main]
+fn main_is_not_async() {}
+
+#[tokio::main]
+async fn main_fn_has_args(_x: u8) {}
+
+#[tokio::main(foo)]
+async fn main_attr_has_unknown_args() {}
+
+#[tokio::main(multi_thread::bar)]
+async fn main_attr_has_path_args() {}
+
+#[tokio::test]
+fn test_is_not_async() {}
+
+#[tokio::test]
+async fn test_fn_has_args(_x: u8) {}
+
+#[tokio::test(foo)]
+async fn test_attr_has_args() {}
+
+#[tokio::test]
+#[test]
+async fn test_has_second_test_attr() {}
+
+fn main() {}

build-tests/tests/fail/macros_invalid_input.stderr

@@ -0,0 +1,47 @@
+error: the async keyword is missing from the function declaration
+ --> $DIR/macros_invalid_input.rs:4:1
+  |
+4 | fn main_is_not_async() {}
+  | ^^
+
+error: the main function cannot accept arguments
+ --> $DIR/macros_invalid_input.rs:7:27
+  |
+7 | async fn main_fn_has_args(_x: u8) {}
+  |                           ^^^^^^
+
+error: Unknown attribute foo is specified
+ --> $DIR/macros_invalid_input.rs:9:15
+  |
+9 | #[tokio::main(foo)]
+  |               ^^^
+
+error: Must have specified ident
+  --> $DIR/macros_invalid_input.rs:12:15
+   |
+12 | #[tokio::main(multi_thread::bar)]
+   |               ^^^^^^^^^^^^^^^^^
+
+error: the async keyword is missing from the function declaration
+  --> $DIR/macros_invalid_input.rs:16:1
+   |
+16 | fn test_is_not_async() {}
+   | ^^
+
+error: the test function cannot accept arguments
+  --> $DIR/macros_invalid_input.rs:19:27
+   |
+19 | async fn test_fn_has_args(_x: u8) {}
+   |                           ^^^^^^
+
+error: unexpected token
+  --> $DIR/macros_invalid_input.rs:21:15
+   |
+21 | #[tokio::test(foo)]
+   |               ^^^
+
+error: second test attribute is supplied
+  --> $DIR/macros_invalid_input.rs:25:1
+   |
+25 | #[test]
+   | ^^^^^^^

build-tests/tests/features.rs

@@ -37,6 +37,7 @@ fn tokio_with_net() {
     // net is present
     use build_tests::tokio::net;
 }
+
 #[test]
 fn compile_fail() {
     let t = trybuild::TestCases::new();
@@ -44,6 +45,9 @@ fn compile_fail() {
     #[cfg(feature = "executor-without-current-thread")]
     t.compile_fail("tests/fail/executor_without_current_thread.rs");
 
+    #[cfg(feature = "macros-invalid-input")]
+    t.compile_fail("tests/fail/macros_invalid_input.rs");
+
     #[cfg(feature = "net-no-features")]
     {
         t.compile_fail("tests/fail/net_without_tcp_missing_tcp.rs");

tokio-macros/src/lib.rs

@@ -124,8 +124,9 @@ pub fn main(args: TokenStream, item: TokenStream) -> TokenStream {
 /// }
 /// ```
 #[proc_macro_attribute]
-pub fn test(_attr: TokenStream, item: TokenStream) -> TokenStream {
+pub fn test(args: TokenStream, item: TokenStream) -> TokenStream {
     let input = syn::parse_macro_input!(item as syn::ItemFn);
+    let _ = syn::parse_macro_input!(args as syn::parse::Nothing);
 
     let ret = &input.sig.output;
     let name = &input.sig.ident;
@@ -143,7 +144,7 @@ pub fn test(_attr: TokenStream, item: TokenStream) -> TokenStream {
 
     if input.sig.asyncness.is_none() {
         let msg = "the async keyword is missing from the function declaration";
-        return syn::Error::new_spanned(&input, msg)
+        return syn::Error::new_spanned(&input.sig.fn_token, msg)
             .to_compile_error()
             .into();
     } else if !input.sig.inputs.is_empty() {