auto merge of #11720 : sfackler/rust/macro-export-source, r=alexcrichton

The old method of serializing the AST gives totally bogus spans if the
expansion of an imported macro causes compilation errors. The best
solution seems to be to serialize the actual textual macro definition
and load it the same way the std-macros are. I'm not totally confident
that getting the source from the CodeMap will always do the right thing,
but it seems to work in simple cases.

10 files changed, 31 insertions, 15 deletions

diff --git a/src/librustc/metadata/creader.rs b/src/librustc/metadata/creader.rs
index 1d992833112..fa2e94b6f8f 100644
--- a/src/librustc/metadata/creader.rs
+++ b/src/librustc/metadata/creader.rs
@@ -420,7 +420,7 @@ impl CrateLoader for Loader {
         }
     }
 
-    fn get_exported_macros(&mut self, cnum: ast::CrateNum) -> ~[@ast::Item] {
+    fn get_exported_macros(&mut self, cnum: ast::CrateNum) -> ~[~str] {
         csearch::get_exported_macros(self.env.sess.cstore, cnum)
     }
 
diff --git a/src/librustc/metadata/csearch.rs b/src/librustc/metadata/csearch.rs
index ea55e0d3d72..8d5be0cfb82 100644
--- a/src/librustc/metadata/csearch.rs
+++ b/src/librustc/metadata/csearch.rs
@@ -307,7 +307,7 @@ pub fn get_macro_registrar_fn(cstore: @cstore::CStore,
 
 pub fn get_exported_macros(cstore: @cstore::CStore,
                            crate_num: ast::CrateNum)
-                           -> ~[@ast::Item] {
+                           -> ~[~str] {
     let cdata = cstore.get_crate_data(crate_num);
     decoder::get_exported_macros(cdata)
 }
diff --git a/src/librustc/metadata/decoder.rs b/src/librustc/metadata/decoder.rs
index abf5b051c7d..a7e5082bcbb 100644
--- a/src/librustc/metadata/decoder.rs
+++ b/src/librustc/metadata/decoder.rs
@@ -23,7 +23,6 @@ use metadata::tydecode::{parse_ty_data, parse_def_id,
 use middle::ty::{ImplContainer, TraitContainer};
 use middle::ty;
 use middle::typeck;
-use middle::astencode;
 use middle::astencode::vtable_decoder_helpers;
 
 use std::at_vec;
@@ -1282,12 +1281,12 @@ pub fn get_macro_registrar_fn(cdata: Cmd) -> Option<ast::DefId> {
         .map(|doc| item_def_id(doc, cdata))
 }
 
-pub fn get_exported_macros(cdata: Cmd) -> ~[@ast::Item] {
+pub fn get_exported_macros(cdata: Cmd) -> ~[~str] {
     let macros = reader::get_doc(reader::Doc(cdata.data()),
                                  tag_exported_macros);
     let mut result = ~[];
     reader::tagged_docs(macros, tag_macro_def, |macro_doc| {
-        result.push(astencode::decode_exported_macro(macro_doc));
+        result.push(macro_doc.as_str());
         true
     });
     result
diff --git a/src/librustc/metadata/encoder.rs b/src/librustc/metadata/encoder.rs
index a7c82ba4317..114b74b02de 100644
--- a/src/librustc/metadata/encoder.rs
+++ b/src/librustc/metadata/encoder.rs
@@ -37,6 +37,7 @@ use syntax::ast_map;
 use syntax::ast_util::*;
 use syntax::attr;
 use syntax::attr::AttrMetaMethods;
+use syntax::codemap;
 use syntax::diagnostic::SpanHandler;
 use syntax::parse::token::special_idents;
 use syntax::ast_util;
@@ -71,6 +72,7 @@ pub struct EncodeParams<'a> {
     cstore: @cstore::CStore,
     encode_inlined_item: encode_inlined_item<'a>,
     reachable: @RefCell<HashSet<ast::NodeId>>,
+    codemap: @codemap::CodeMap,
 }
 
 struct Stats {
@@ -101,6 +103,7 @@ pub struct EncodeContext<'a> {
     encode_inlined_item: encode_inlined_item<'a>,
     type_abbrevs: abbrev_map,
     reachable: @RefCell<HashSet<ast::NodeId>>,
+    codemap: @codemap::CodeMap,
 }
 
 pub fn reachable(ecx: &EncodeContext, id: NodeId) -> bool {
@@ -1714,8 +1717,10 @@ impl<'a, 'b> Visitor<()> for MacroDefVisitor<'a, 'b> {
     fn visit_item(&mut self, item: &Item, _: ()) {
         match item.node {
             ItemMac(..) => {
+                let def = self.ecx.codemap.span_to_snippet(item.span)
+                    .expect("Unable to find source for macro");
                 self.ebml_w.start_tag(tag_macro_def);
-                astencode::encode_exported_macro(self.ebml_w, item);
+                self.ebml_w.wr_str(def);
                 self.ebml_w.end_tag();
             }
             _ => {}
@@ -1881,6 +1886,7 @@ fn encode_metadata_inner(wr: &mut MemWriter, parms: EncodeParams, crate: &Crate)
         link_meta,
         reachable,
         non_inlineable_statics,
+        codemap,
         ..
     } = parms;
     let type_abbrevs = @RefCell::new(HashMap::new());
@@ -1897,6 +1903,7 @@ fn encode_metadata_inner(wr: &mut MemWriter, parms: EncodeParams, crate: &Crate)
         encode_inlined_item: encode_inlined_item,
         type_abbrevs: type_abbrevs,
         reachable: reachable,
+        codemap: codemap,
      };
 
     let mut ebml_w = writer::Encoder(wr);
diff --git a/src/librustc/middle/trans/base.rs b/src/librustc/middle/trans/base.rs
index c654bbbd709..5b246daa6c5 100644
--- a/src/librustc/middle/trans/base.rs
+++ b/src/librustc/middle/trans/base.rs
@@ -2678,6 +2678,7 @@ pub fn crate_ctxt_to_encode_parms<'r>(cx: &'r CrateContext, ie: encoder::encode_
             cstore: cx.sess.cstore,
             encode_inlined_item: ie,
             reachable: cx.reachable,
+            codemap: cx.sess.codemap,
         }
 }
 
diff --git a/src/librustpkg/util.rs b/src/librustpkg/util.rs
index 9042dfea256..57fcf564c5d 100644
--- a/src/librustpkg/util.rs
+++ b/src/librustpkg/util.rs
@@ -623,7 +623,7 @@ impl<'a> base::CrateLoader for CrateLoader<'a> {
         self.loader.load_crate(crate)
     }
 
-    fn get_exported_macros(&mut self, cnum: ast::CrateNum) -> ~[@ast::Item] {
+    fn get_exported_macros(&mut self, cnum: ast::CrateNum) -> ~[~str] {
         self.loader.get_exported_macros(cnum)
     }
 
diff --git a/src/libsyntax/ext/base.rs b/src/libsyntax/ext/base.rs
index a6ad7b2a550..2c817365390 100644
--- a/src/libsyntax/ext/base.rs
+++ b/src/libsyntax/ext/base.rs
@@ -299,7 +299,7 @@ pub struct MacroCrate {
 
 pub trait CrateLoader {
     fn load_crate(&mut self, crate: &ast::ViewItem) -> MacroCrate;
-    fn get_exported_macros(&mut self, crate_num: ast::CrateNum) -> ~[@ast::Item];
+    fn get_exported_macros(&mut self, crate_num: ast::CrateNum) -> ~[~str];
     fn get_registrar_symbol(&mut self, crate_num: ast::CrateNum) -> Option<~str>;
 }
 
diff --git a/src/libsyntax/ext/expand.rs b/src/libsyntax/ext/expand.rs
index f547f32e21d..0534aa39848 100644
--- a/src/libsyntax/ext/expand.rs
+++ b/src/libsyntax/ext/expand.rs
@@ -406,9 +406,20 @@ pub fn expand_view_item(vi: &ast::ViewItem,
 fn load_extern_macros(crate: &ast::ViewItem, fld: &mut MacroExpander) {
     let MacroCrate { lib, cnum } = fld.cx.loader.load_crate(crate);
 
+    let crate_name = match crate.node {
+        ast::ViewItemExternMod(ref name, _, _) => token::ident_to_str(name),
+        _ => unreachable!(),
+    };
+    let name = format!("<{} macros>", crate_name).to_managed();
+
     let exported_macros = fld.cx.loader.get_exported_macros(cnum);
-    for &it in exported_macros.iter() {
-        expand_item_mac(it, fld);
+    for source in exported_macros.iter() {
+        let item = parse::parse_item_from_source_str(name,
+                                                     source.to_managed(),
+                                                     fld.cx.cfg(),
+                                                     fld.cx.parse_sess())
+                .expect("expected a serialized item");
+        expand_item_mac(item, fld);
     }
 
     let path = match lib {
@@ -944,7 +955,6 @@ pub fn inject_std_macros(parse_sess: @parse::ParseSess,
     let sm = match parse_item_from_source_str(@"<std-macros>",
                                               std_macros(),
                                               cfg.clone(),
-                                              ~[],
                                               parse_sess) {
         Some(item) => item,
         None => fail!("expected core macros to parse correctly")
@@ -1212,7 +1222,7 @@ mod test {
             fail!("lolwut")
         }
 
-        fn get_exported_macros(&mut self, _: ast::CrateNum) -> ~[@ast::Item] {
+        fn get_exported_macros(&mut self, _: ast::CrateNum) -> ~[~str] {
             fail!("lolwut")
         }
 
@@ -1289,7 +1299,7 @@ mod test {
         let item_ast = parse::parse_item_from_source_str(
             @"<test>",
             src,
-            cfg,~[],sess);
+            cfg,sess);
         match item_ast {
             Some(_) => (), // success
             None => fail!("expected this to parse")
diff --git a/src/libsyntax/ext/quote.rs b/src/libsyntax/ext/quote.rs
index f840bde6dc1..6faed270875 100644
--- a/src/libsyntax/ext/quote.rs
+++ b/src/libsyntax/ext/quote.rs
@@ -250,7 +250,6 @@ pub mod rt {
                 @"<quote expansion>",
                 s,
                 self.cfg(),
-                ~[],
                 self.parse_sess());
             match res {
                 Some(ast) => ast,
diff --git a/src/libsyntax/parse/mod.rs b/src/libsyntax/parse/mod.rs
index 9713f331147..e026a11cafe 100644
--- a/src/libsyntax/parse/mod.rs
+++ b/src/libsyntax/parse/mod.rs
@@ -130,10 +130,10 @@ pub fn parse_item_from_source_str(
     name: @str,
     source: @str,
     cfg: ast::CrateConfig,
-    attrs: ~[ast::Attribute],
     sess: @ParseSess
 ) -> Option<@ast::Item> {
     let mut p = new_parser_from_source_str(sess, cfg, name, source);
+    let attrs = p.parse_outer_attributes();
     maybe_aborted(p.parse_item(attrs),p)
 }