Refactor how doc_mod works so rustfmt finds those modules easily.

Author: emilio

src/lib.rs

@@ -42,22 +42,29 @@ extern crate lazy_static;
 // undocumented. Normal builds, however, will leave the module private, so that
 // we don't expose internals to library consumers.
 macro_rules! doc_mod {
-    ($m:ident) => {
+    ($m:ident, $doc_mod_name:ident) => {
         cfg_if! {
             if #[cfg(feature = "_docs")] {
-                pub mod $m;
+                pub mod $doc_mod_name {
+                    //! Autogenerated documentation module.
+                    pub use super::$m::*;
+                }
             } else {
-                mod $m;
             }
         }
     };
 }
 
 mod clangll;
-doc_mod!(clang);
-doc_mod!(ir);
-doc_mod!(parse);
-doc_mod!(regex_set);
+mod clang;
+mod ir;
+mod parse;
+mod regex_set;
+
+doc_mod!(clang, clang_docs);
+doc_mod!(ir, ir_docs);
+doc_mod!(parse, parse_docs);
+doc_mod!(regex_set, regex_set_docs);
 
 mod codegen {
     include!(concat!(env!("OUT_DIR"), "/codegen.rs"));