Add DefinedMacros handler (#1683)

**Stack**:
- #1686
- #1685
- #1684
- #1683 ⬅
- #1718


⚠️ *Part of a stack created by [spr](https://github.com/ejoffe/spr). Do
not merge manually using the UI - doing so may have unexpected results.*

Author: Draggu

scarb/src/compiler/plugin/proc_macro/ffi.rs

@@ -107,7 +107,7 @@ impl ProcMacroInstance {
         self.package_id
     }
 
-    pub fn declared_attributes(&self) -> Vec<String> {
+    pub fn declared_attributes_and_executables(&self) -> Vec<String> {
         self.get_expansions()
             .iter()
             .filter(|e| e.kind == ExpansionKind::Attr || e.kind == ExpansionKind::Executable)
@@ -116,6 +116,15 @@ impl ProcMacroInstance {
             .collect()
     }
 
+    pub fn declared_attributes(&self) -> Vec<String> {
+        self.get_expansions()
+            .iter()
+            .filter(|e| e.kind == ExpansionKind::Attr)
+            .map(|e| e.name.clone())
+            .map(Into::into)
+            .collect()
+    }
+
     pub fn declared_derives(&self) -> Vec<String> {
         self.get_expansions()
             .iter()
@@ -134,6 +143,15 @@ impl ProcMacroInstance {
             .collect()
     }
 
+    pub fn inline_macros(&self) -> Vec<String> {
+        self.get_expansions()
+            .iter()
+            .filter(|e| e.kind == ExpansionKind::Inline)
+            .map(|e| e.name.clone())
+            .map(Into::into)
+            .collect()
+    }
+
     /// Apply expansion to token stream.
     ///
     /// This function implements the actual calls to functions from the dynamic library.

scarb/src/compiler/plugin/proc_macro/host.rs

@@ -946,7 +946,7 @@ impl MacroPlugin for ProcMacroHostPlugin {
     fn declared_attributes(&self) -> Vec<String> {
         self.macros
             .iter()
-            .flat_map(|m| m.declared_attributes())
+            .flat_map(|m| m.declared_attributes_and_executables())
             .chain(vec![FULL_PATH_MARKER_KEY.to_string()])
             .collect()
     }
@@ -1101,4 +1101,8 @@ impl ProcMacroHost {
     pub fn into_plugin(self) -> Result<ProcMacroHostPlugin> {
         ProcMacroHostPlugin::try_new(self.macros)
     }
+
+    pub fn macros(&self) -> &[Arc<ProcMacroInstance>] {
+        &self.macros
+    }
 }

scarb/src/ops/proc_macro_server/methods/defined_macros.rs

@@ -0,0 +1,49 @@
+use std::sync::Arc;
+
+use anyhow::Result;
+use scarb_proc_macro_server_types::methods::defined_macros::{
+    DefinedMacros, DefinedMacrosResponse,
+};
+
+use super::Handler;
+use crate::compiler::plugin::proc_macro::ProcMacroHost;
+
+impl Handler for DefinedMacros {
+    fn handle(
+        proc_macro_host: Arc<ProcMacroHost>,
+        _params: Self::Params,
+    ) -> Result<Self::Response> {
+        let mut response = proc_macro_host
+            .macros()
+            .iter()
+            .map(|e| DefinedMacrosResponse {
+                attributes: e.declared_attributes(),
+                inline_macros: e.inline_macros(),
+                derives: e.declared_derives(),
+                executables: e.executable_attributes(),
+            })
+            .reduce(|mut acc, defined_macros| {
+                acc.attributes.extend(defined_macros.attributes);
+                acc.inline_macros.extend(defined_macros.inline_macros);
+                acc.derives.extend(defined_macros.derives);
+                acc.executables.extend(defined_macros.executables);
+
+                acc
+            })
+            .unwrap_or_default();
+
+        response.attributes.sort();
+        response.attributes.dedup();
+
+        response.inline_macros.sort();
+        response.inline_macros.dedup();
+
+        response.derives.sort();
+        response.derives.dedup();
+
+        response.executables.sort();
+        response.executables.dedup();
+
+        Ok(response)
+    }
+}

scarb/src/ops/proc_macro_server/methods/mod.rs

@@ -0,0 +1,12 @@
+use std::sync::Arc;
+
+use anyhow::Result;
+use scarb_proc_macro_server_types::methods::Method;
+
+use crate::compiler::plugin::proc_macro::ProcMacroHost;
+
+pub mod defined_macros;
+
+pub trait Handler: Method {
+    fn handle(proc_macro_host: Arc<ProcMacroHost>, params: Self::Params) -> Result<Self::Response>;
+}

scarb/src/ops/proc_macro_server/mod.rs

@@ -1,28 +1,35 @@
 use std::num::NonZero;
+use std::sync::Arc;
 use std::thread::available_parallelism;
 
 use anyhow::{anyhow, Result};
 use connection::Connection;
 use crossbeam_channel::{Receiver, Sender};
+use methods::Handler;
 use scarb_proc_macro_server_types::jsonrpc::{ResponseError, RpcRequest, RpcResponse};
+use scarb_proc_macro_server_types::methods::defined_macros::DefinedMacros;
+use scarb_proc_macro_server_types::methods::Method;
 use serde_json::Value;
 
 use crate::compiler::plugin::proc_macro::ProcMacroHost;
 
 mod connection;
+mod methods;
 
-pub fn start_proc_macro_server(_proc_macros: ProcMacroHost) -> Result<()> {
+pub fn start_proc_macro_server(proc_macros: ProcMacroHost) -> Result<()> {
     let connection = Connection::new();
     let available_parallelism = available_parallelism().map(NonZero::get).unwrap_or(4);
+    let proc_macros = Arc::new(proc_macros);
 
     for i in 0..available_parallelism {
         let receiver = connection.receiver.clone();
         let sender = connection.sender.clone();
+        let proc_macros = proc_macros.clone();
 
         std::thread::Builder::new()
             .name(format!("proc-macro-server-worker-thread-{i}"))
             .spawn(move || {
-                handle_requests(receiver, sender);
+                handle_requests(proc_macros, receiver, sender);
             })
             .expect("failed to spawn thread");
     }
@@ -32,10 +39,14 @@ pub fn start_proc_macro_server(_proc_macros: ProcMacroHost) -> Result<()> {
     Ok(())
 }
 
-fn handle_requests(receiver: Receiver<RpcRequest>, sender: Sender<RpcResponse>) {
+fn handle_requests(
+    proc_macros: Arc<ProcMacroHost>,
+    receiver: Receiver<RpcRequest>,
+    sender: Sender<RpcResponse>,
+) {
     for request in receiver {
         let id = request.id;
-        let response = route_request(request);
+        let response = route_request(proc_macros.clone(), request);
 
         let response = match response {
             Ok(result) => RpcResponse {
@@ -56,10 +67,14 @@ fn handle_requests(receiver: Receiver<RpcRequest>, sender: Sender<RpcResponse>)
     }
 }
 
-fn route_request(request: RpcRequest) -> Result<Value> {
-    #[allow(clippy::match_single_binding)]
+fn route_request(proc_macros: Arc<ProcMacroHost>, request: RpcRequest) -> Result<Value> {
     match request.method.as_str() {
-        //TODO add method handlers
+        DefinedMacros::METHOD => run_handler::<DefinedMacros>(proc_macros.clone(), request.value),
         _ => Err(anyhow!("method not found")),
     }
 }
+
+fn run_handler<M: Handler>(proc_macros: Arc<ProcMacroHost>, value: Value) -> Result<Value> {
+    M::handle(proc_macros, serde_json::from_value(value).unwrap())
+        .map(|res| serde_json::to_value(res).unwrap())
+}

scarb/tests/proc_macro_server.rs

@@ -0,0 +1,38 @@
+use assert_fs::prelude::PathChild;
+use assert_fs::TempDir;
+use scarb_proc_macro_server_types::methods::defined_macros::DefinedMacros;
+use scarb_proc_macro_server_types::methods::defined_macros::DefinedMacrosParams;
+use scarb_test_support::cairo_plugin_project_builder::CairoPluginProjectBuilder;
+use scarb_test_support::proc_macro_server::ProcMacroClient;
+use scarb_test_support::proc_macro_server::SIMPLE_MACROS;
+use scarb_test_support::project_builder::ProjectBuilder;
+
+#[test]
+fn defined_macros() {
+    let t = TempDir::new().unwrap();
+    let plugin_package = t.child("some");
+
+    CairoPluginProjectBuilder::default()
+        .lib_rs(SIMPLE_MACROS)
+        .build(&plugin_package);
+
+    let project = t.child("test_package");
+
+    ProjectBuilder::start()
+        .name("test_package")
+        .version("1.0.0")
+        .lib_cairo("")
+        .dep("some", plugin_package)
+        .build(&project);
+
+    let mut proc_macro_server = ProcMacroClient::new(&project);
+
+    let response = proc_macro_server
+        .request_and_wait::<DefinedMacros>(DefinedMacrosParams {})
+        .unwrap();
+
+    assert_eq!(response.attributes, vec!["some".to_string()]);
+    assert_eq!(response.derives, vec!["some_derive".to_string()]);
+    assert_eq!(response.inline_macros, vec!["inline_some".to_string()]);
+    assert_eq!(response.executables, vec!["some_executable".to_string()]);
+}