rustc: Add a path attribute for crate directives

The path information was an optional "filename" component of crate
directive AST. It is now replaced by an attribute with metadata named
"path".

With this commit, a directive

  mod foo = "foo.rs";

should be written as:

  #[path = "foo.rs"]
  mod foo;

Closes issue #906.

2 files changed, 16 insertions, 15 deletions

diff --git a/src/comp/syntax/parse/eval.rs b/src/comp/syntax/parse/eval.rs
index 2c1c0155cf0..bc8a51e1f34 100644
--- a/src/comp/syntax/parse/eval.rs
+++ b/src/comp/syntax/parse/eval.rs
@@ -1,4 +1,5 @@
 
+import front::attr;
 import std::{option, result, io, fs};
 import std::option::{some, none};
 import syntax::ast;
@@ -86,13 +87,21 @@ fn parse_companion_mod(cx: ctx, prefix: str, suffix: option::t<str>)
     }
 }
 
+fn cdir_path_opt(id: str, attrs: [ast::attribute]) -> str {
+    alt attr::get_meta_item_value_str_by_name(attrs, "path") {
+      some(d) {
+        ret d;
+      }
+      none. { ret id; }
+    }
+}
+
 fn eval_crate_directive(cx: ctx, cdir: @ast::crate_directive, prefix: str,
                         &view_items: [@ast::view_item],
                         &items: [@ast::item]) {
     alt cdir.node {
-      ast::cdir_src_mod(id, file_opt, attrs) {
-        let file_path = id + ".rs";
-        alt file_opt { some(f) { file_path = f; } none. { } }
+      ast::cdir_src_mod(id, attrs) {
+        let file_path = cdir_path_opt(id + ".rs", attrs);
         let full_path =
             if std::fs::path_is_absolute(file_path) {
                 file_path
@@ -113,9 +122,8 @@ fn eval_crate_directive(cx: ctx, cdir: @ast::crate_directive, prefix: str,
         cx.byte_pos = p0.get_byte_pos();
         items += [i];
       }
-      ast::cdir_dir_mod(id, dir_opt, cdirs, attrs) {
-        let path = id;
-        alt dir_opt { some(d) { path = d; } none. { } }
+      ast::cdir_dir_mod(id, cdirs, attrs) {
+        let path = cdir_path_opt(id, attrs);
         let full_path =
             if std::fs::path_is_absolute(path) {
                 path
diff --git a/src/comp/syntax/parse/parser.rs b/src/comp/syntax/parse/parser.rs
index 4f81a1dfe73..82c477a7d96 100644
--- a/src/comp/syntax/parse/parser.rs
+++ b/src/comp/syntax/parse/parser.rs
@@ -2475,19 +2475,12 @@ fn parse_crate_directive(p: parser, first_outer_attr: [ast::attribute]) ->
     if expect_mod || is_word(p, "mod") {
         expect_word(p, "mod");
         let id = parse_ident(p);
-        let file_opt =
-            alt p.peek() {
-              token::EQ. { p.bump(); some(parse_str(p)) }
-              _ {
-                attr::get_meta_item_value_str_by_name(outer_attrs, "path")
-              }
-            };
         alt p.peek() {
           // mod x = "foo.rs";
           token::SEMI. {
             let hi = p.get_hi_pos();
             p.bump();
-            ret spanned(lo, hi, ast::cdir_src_mod(id, file_opt, outer_attrs));
+            ret spanned(lo, hi, ast::cdir_src_mod(id, outer_attrs));
           }
           // mod x = "foo_dir" { ...directives... }
           token::LBRACE. {
@@ -2500,7 +2493,7 @@ fn parse_crate_directive(p: parser, first_outer_attr: [ast::attribute]) ->
             let hi = p.get_hi_pos();
             expect(p, token::RBRACE);
             ret spanned(lo, hi,
-                        ast::cdir_dir_mod(id, file_opt, cdirs, mod_attrs));
+                        ast::cdir_dir_mod(id, cdirs, mod_attrs));
           }
           t { unexpected(p, t); }
         }