rtfm! macro take 2

macros/src/lib.rs

@@ -0,0 +1,63 @@
+#![feature(plugin_registrar)]
+#![feature(proc_macro_internals)]
+#![feature(rustc_private)]
+#![recursion_limit = "128"]
+
+extern crate proc_macro;
+#[macro_use]
+extern crate quote;
+extern crate rustc_errors;
+extern crate rustc_plugin;
+extern crate syn;
+extern crate syntax as rustc_syntax;
+
+use proc_macro::TokenStream;
+use rustc_errors::Handler;
+use rustc_errors::emitter::ColorConfig;
+use rustc_plugin::Registry;
+use rustc_syntax::codemap::{CodeMap, FilePathMapping};
+use rustc_syntax::ext::base::SyntaxExtension;
+use rustc_syntax::parse::ParseSess;
+use rustc_syntax::symbol::Symbol;
+use rustc_syntax::tokenstream::TokenStream as TokenStream_;
+use std::rc::Rc;
+use std::str::FromStr;
+
+mod check;
+mod syntax;
+mod trans;
+mod util;
+
+fn expand_rtfm(ts: TokenStream_) -> TokenStream_ {
+    let input = format!("{}", ts);
+
+    let app = syntax::parse::app(&input);
+    let ceilings = util::compute_ceilings(&app);
+    check::resources(&app.resources, &ceilings);
+
+    let output = format!("{}", trans::app(&app, &ceilings));
+
+    let mapping = FilePathMapping::empty();
+    let codemap = Rc::new(CodeMap::new(mapping));
+
+    let tty_handler = Handler::with_tty_emitter(
+        ColorConfig::Auto,
+        true,
+        false,
+        Some(codemap.clone()),
+    );
+
+    let sess = ParseSess::with_span_handler(tty_handler, codemap.clone());
+    proc_macro::__internal::set_parse_sess(&sess, || {
+        let ts = TokenStream::from_str(&output).unwrap();
+        proc_macro::__internal::token_stream_inner(ts)
+    })
+}
+
+#[plugin_registrar]
+pub fn plugin_registrar(reg: &mut Registry) {
+    reg.register_syntax_extension(
+        Symbol::intern("rtfm"),
+        SyntaxExtension::ProcMacro(Box::new(expand_rtfm)),
+    );
+}