rust/crates/proc_macro_api/src/lib.rs
2020-08-15 15:34:56 +02:00

112 lines
3.5 KiB
Rust

//! Client-side Proc-Macro crate
//!
//! We separate proc-macro expanding logic to an extern program to allow
//! different implementations (e.g. wasm or dylib loading). And this crate
//! is used to provide basic infrastructure for communication between two
//! processes: Client (RA itself), Server (the external program)
mod rpc;
mod process;
pub mod msg;
use std::{
ffi::OsStr,
io,
path::{Path, PathBuf},
sync::Arc,
};
use tt::{SmolStr, Subtree};
use crate::process::{ProcMacroProcessSrv, ProcMacroProcessThread};
pub use rpc::{ExpansionResult, ExpansionTask, ListMacrosResult, ListMacrosTask, ProcMacroKind};
#[derive(Debug, Clone)]
pub struct ProcMacroProcessExpander {
process: Arc<ProcMacroProcessSrv>,
dylib_path: PathBuf,
name: SmolStr,
}
impl Eq for ProcMacroProcessExpander {}
impl PartialEq for ProcMacroProcessExpander {
fn eq(&self, other: &Self) -> bool {
self.name == other.name
&& self.dylib_path == other.dylib_path
&& Arc::ptr_eq(&self.process, &other.process)
}
}
impl tt::TokenExpander for ProcMacroProcessExpander {
fn expand(
&self,
subtree: &Subtree,
_attr: Option<&Subtree>,
) -> Result<Subtree, tt::ExpansionError> {
self.process.custom_derive(&self.dylib_path, subtree, &self.name)
}
}
#[derive(Debug)]
enum ProcMacroClientKind {
Process { process: Arc<ProcMacroProcessSrv>, thread: ProcMacroProcessThread },
Dummy,
}
#[derive(Debug)]
pub struct ProcMacroClient {
kind: ProcMacroClientKind,
}
impl ProcMacroClient {
pub fn extern_process(
process_path: PathBuf,
args: impl IntoIterator<Item = impl AsRef<OsStr>>,
) -> io::Result<ProcMacroClient> {
let (thread, process) = ProcMacroProcessSrv::run(process_path, args)?;
Ok(ProcMacroClient {
kind: ProcMacroClientKind::Process { process: Arc::new(process), thread },
})
}
pub fn dummy() -> ProcMacroClient {
ProcMacroClient { kind: ProcMacroClientKind::Dummy }
}
pub fn by_dylib_path(&self, dylib_path: &Path) -> Vec<(SmolStr, Arc<dyn tt::TokenExpander>)> {
match &self.kind {
ProcMacroClientKind::Dummy => vec![],
ProcMacroClientKind::Process { process, .. } => {
let macros = match process.find_proc_macros(dylib_path) {
Err(err) => {
eprintln!("Failed to find proc macros. Error: {:#?}", err);
return vec![];
}
Ok(macros) => macros,
};
macros
.into_iter()
.filter_map(|(name, kind)| {
match kind {
ProcMacroKind::CustomDerive | ProcMacroKind::FuncLike => {
let name = SmolStr::new(&name);
let expander: Arc<dyn tt::TokenExpander> =
Arc::new(ProcMacroProcessExpander {
process: process.clone(),
name: name.clone(),
dylib_path: dylib_path.into(),
});
Some((name, expander))
}
// FIXME: Attribute macro are currently unsupported.
ProcMacroKind::Attr => None,
}
})
.collect()
}
}
}
}