Add wstd::main and wstd::test macros for WASIp3

examples/macro_main.rs

@@ -0,0 +1,9 @@
+#![cfg_attr(not(target_os = "wasi"), no_main)]
+#![cfg(target_os = "wasi")]
+
+//! Verifies that the `main` macro is compiling.
+
+#[wstd::main]
+async fn main() {
+    println!("Hello world");
+}

src/lib.rs

@@ -69,15 +69,25 @@ pub mod net;
 pub mod rand;
 #[cfg(all(target_os = "wasi", target_env = "p2"))]
 pub mod runtime;
+#[cfg(all(target_os = "wasi", target_env = "p3"))]
+pub mod runtime {
+    pub fn block_on<F, T>(fut: F) -> F::Output
+    where
+        F: Future<Output = T>,
+        T: 'static,
+    {
+        wasip3::wit_bindgen::block_on(fut)
+    }
+}
 #[cfg(all(target_os = "wasi", target_env = "p2"))]
 pub mod task;
 #[cfg(all(target_os = "wasi", target_env = "p2"))]
 pub mod time;
 
 #[cfg(all(target_os = "wasi", target_env = "p2"))]
-pub use wstd_macro::{
-    attr_macro_http_server as http_server, attr_macro_main as main, attr_macro_test as test,
-};
+pub use wstd_macro::attr_macro_http_server as http_server;
+
+pub use wstd_macro::{attr_macro_main as main, attr_macro_test as test};
 
 // Re-export the active WASI backend crate for use only by `wstd-macro` macros.
 // The proc macros need to generate code that uses these definitions, but we

tests/http_first_byte_timeout.rs

@@ -2,7 +2,7 @@
 
 use wstd::http::{Body, Client, Request, error::ErrorCode};
 
-#[wstd::main]
+#[wstd::test]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
     // Set first byte timeout to 1/2 second.
     let mut client = Client::new();

tests/macro_test.rs

@@ -0,0 +1,12 @@
+// Verify that the test macro is acutally running.
+
+#[wstd::test]
+async fn computation() -> Result<(), String> {
+    assert_eq!(1 + 1, 2);
+    Ok(())
+}
+
+#[wstd::test]
+async fn second_computation() {
+    assert_eq!(1 + 1, 2);
+}