proc-macro: Timeout for tests

Signed-off-by: Alexandru Vasile <alexandru.vasile@parity.io>

testing/integration-tests/proc-macro/Cargo.toml

@@ -0,0 +1,21 @@
+[package]
+name = "integration-tests-proc-macro"
+version.workspace = true
+authors.workspace = true
+edition.workspace = true
+rust-version.workspace = true
+publish = false
+
+license.workspace = true
+repository.workspace = true
+documentation.workspace = true
+homepage.workspace = true
+description = "Subxt integration tests proc-macros"
+
+[lib]
+proc-macro = true
+
+[dependencies]
+syn = { workspace = true }
+proc-macro2 = { workspace = true }
+quote = { workspace = true }

testing/integration-tests/proc-macro/src/lib.rs

@@ -0,0 +1,80 @@
+// Copyright 2019-2023 Parity Technologies (UK) Ltd.
+// This file is dual-licensed as Apache-2.0 or GPL-3.0.
+// see LICENSE for license details.
+
+extern crate proc_macro;
+use proc_macro::TokenStream;
+
+use quote::{format_ident, quote};
+use syn::{
+    parse::{Parse, ParseStream},
+    Error,
+};
+
+#[proc_macro_attribute]
+pub fn subxt_test(attr: TokenStream, item: TokenStream) -> TokenStream {
+    let subxt_attr = match syn::parse::<SubxtTestAttr>(attr) {
+        Ok(subxt_attr) => subxt_attr,
+        Err(err) => return err.into_compile_error().into(),
+    };
+    let timeout_duration = subxt_attr.timeout.unwrap_or(60 * 5);
+
+    let func: syn::ItemFn = match syn::parse(item) {
+        Ok(func) => func,
+        Err(err) => return err.into_compile_error().into(),
+    };
+
+    let func_attrs = &func.attrs;
+    let func_vis = &func.vis;
+    let func_sig = &func.sig;
+    let func_block = &func.block;
+    let func_output = &func.sig.output;
+
+    let func_name = &func.sig.ident;
+    let inner_func_name = format_ident!("{}_inner", func_name);
+
+    let result = quote! {
+        #[tokio::test]
+        #( #func_attrs )*
+        #func_vis #func_sig #func_output {
+            async fn #inner_func_name() #func_output
+            #func_block
+
+            tokio::time::timeout(std::time::Duration::from_secs(#timeout_duration), #inner_func_name())
+                .await
+                .expect("Test timedout");
+        }
+    };
+    result.into()
+}
+
+mod keywords {
+    syn::custom_keyword!(timeout);
+}
+
+struct SubxtTestAttr {
+    timeout: Option<u64>,
+}
+
+impl Parse for SubxtTestAttr {
+    fn parse(input: ParseStream) -> Result<Self, Error> {
+        if input.is_empty() {
+            return Ok(Self { timeout: None });
+        }
+
+        let _keyword = input.parse::<keywords::timeout>()?;
+        input.parse::<syn::token::Eq>()?;
+        let timeout = input.parse::<syn::LitInt>()?.base10_parse::<u64>()?;
+
+        if !input.is_empty() {
+            return Err(Error::new(
+                input.span(),
+                "Expected tokens: `timeout = value`",
+            ));
+        }
+
+        Ok(Self {
+            timeout: Some(timeout),
+        })
+    }
+}