rust/src/doc/rustc-dev-guide/examples/rustc-driver-example.rs

91 lines
2.3 KiB
Rust

#![feature(rustc_private)]
extern crate rustc_ast;
extern crate rustc_ast_pretty;
extern crate rustc_data_structures;
extern crate rustc_driver;
extern crate rustc_error_codes;
extern crate rustc_errors;
extern crate rustc_hash;
extern crate rustc_hir;
extern crate rustc_interface;
extern crate rustc_middle;
extern crate rustc_session;
extern crate rustc_span;
use std::io;
use std::path::Path;
use std::sync::Arc;
use rustc_ast_pretty::pprust::item_to_string;
use rustc_driver::{Compilation, run_compiler};
use rustc_interface::interface::{Compiler, Config};
use rustc_middle::ty::TyCtxt;
struct MyFileLoader;
impl rustc_span::source_map::FileLoader for MyFileLoader {
fn file_exists(&self, path: &Path) -> bool {
path == Path::new("main.rs")
}
fn read_file(&self, path: &Path) -> io::Result<String> {
if path == Path::new("main.rs") {
Ok(r#"
fn main() {
let message = "Hello, World!";
println!("{message}");
}
"#
.to_string())
} else {
Err(io::Error::other("oops"))
}
}
fn read_binary_file(&self, _path: &Path) -> io::Result<Arc<[u8]>> {
Err(io::Error::other("oops"))
}
}
struct MyCallbacks;
impl rustc_driver::Callbacks for MyCallbacks {
fn config(&mut self, config: &mut Config) {
config.file_loader = Some(Box::new(MyFileLoader));
}
fn after_crate_root_parsing(
&mut self,
_compiler: &Compiler,
krate: &mut rustc_ast::Crate,
) -> Compilation {
for item in &krate.items {
println!("{}", item_to_string(&item));
}
Compilation::Continue
}
fn after_analysis(&mut self, _compiler: &Compiler, tcx: TyCtxt<'_>) -> Compilation {
// Analyze the program and inspect the types of definitions.
for id in tcx.hir().items() {
let hir = tcx.hir();
let item = hir.item(id);
match item.kind {
rustc_hir::ItemKind::Static(_, _, _) | rustc_hir::ItemKind::Fn(_, _, _) => {
let name = item.ident;
let ty = tcx.type_of(item.hir_id().owner.def_id);
println!("{name:?}:\t{ty:?}")
}
_ => (),
}
}
Compilation::Stop
}
}
fn main() {
run_compiler(&["main.rs".to_string()], &mut MyCallbacks);
}