add test and main macros

actix-macros/src/lib.rs

@@ -0,0 +1,96 @@
+//! Macros for use with Tokio
+extern crate proc_macro;
+
+use proc_macro::TokenStream;
+use quote::quote;
+
+/// Marks async function to be executed by actix system.
+///
+/// ## Usage
+///
+/// ```rust
+/// #[actix_rt::main]
+/// async fn main() {
+///     println!("Hello world");
+/// }
+/// ```
+#[proc_macro_attribute]
+#[cfg(not(test))] // Work around for rust-lang/rust#62127
+pub fn main(_: TokenStream, item: TokenStream) -> TokenStream {
+    let input = syn::parse_macro_input!(item as syn::ItemFn);
+
+    let ret = &input.sig.output;
+    let name = &input.sig.ident;
+    let inputs = &input.sig.inputs;
+    let body = &input.block;
+    let attrs = &input.attrs;
+
+    if input.sig.asyncness.is_none() {
+        return syn::Error::new_spanned(input.sig.fn_token, "only async fn is supported")
+            .to_compile_error()
+            .into();
+    }
+
+    (quote! {
+        #(#attrs)*
+        fn #name(#inputs) #ret {
+            actix_rt::System::new("main")
+                .block_on(async { #body })
+        }
+    })
+    .into()
+}
+
+/// Marks async test function to be executed by actix runtime.
+///
+/// ## Usage
+///
+/// ```no_run
+/// #[actix_rt::test]
+/// async fn my_test() {
+///     assert!(true);
+/// }
+/// ```
+#[proc_macro_attribute]
+pub fn test(_: TokenStream, item: TokenStream) -> TokenStream {
+    let input = syn::parse_macro_input!(item as syn::ItemFn);
+
+    let ret = &input.sig.output;
+    let name = &input.sig.ident;
+    let body = &input.block;
+    let attrs = &input.attrs;
+    let mut has_test_attr = false;
+
+    for attr in attrs {
+        if attr.path.is_ident("test") {
+            has_test_attr = true;
+        }
+    }
+
+    if input.sig.asyncness.is_none() {
+        return syn::Error::new_spanned(input.sig.fn_token, "only async fn is supported")
+            .to_compile_error()
+            .into();
+    }
+
+    let result = if has_test_attr {
+        quote! {
+            #(#attrs)*
+            fn #name() #ret {
+                actix_rt::System::new("test")
+                    .block_on(async { #body })
+            }
+        }
+    } else {
+        quote! {
+            #[test]
+            #(#attrs)*
+            fn #name() #ret {
+                actix_rt::System::new("test")
+                    .block_on(async { #body })
+            }
+        }
+    };
+
+    result.into()
+}