store krate information more uniformly

make DefPath store krate and enable uniform access to crate_name/crate_disambiguator

Author: nikomatsakis

src/librustc/front/map/definitions.rs

@@ -59,7 +59,54 @@ pub struct DefData {
     pub node_id: ast::NodeId,
 }
 
-pub type DefPath = Vec<DisambiguatedDefPathData>;
+#[derive(Clone, Debug, PartialEq, Eq, Hash, RustcEncodable, RustcDecodable)]
+pub struct DefPath {
+    /// the path leading from the crate root to the item
+    pub data: Vec<DisambiguatedDefPathData>,
+
+    /// what krate root is this path relative to?
+    pub krate: ast::CrateNum,
+}
+
+impl DefPath {
+    pub fn is_local(&self) -> bool {
+        self.krate == LOCAL_CRATE
+    }
+
+    pub fn make<FN>(start_krate: ast::CrateNum,
+                    start_index: DefIndex,
+                    mut get_key: FN) -> DefPath
+        where FN: FnMut(DefIndex) -> DefKey
+    {
+        let mut krate = start_krate;
+        let mut data = vec![];
+        let mut index = Some(start_index);
+        loop {
+            let p = index.unwrap();
+            let key = get_key(p);
+            match key.disambiguated_data.data {
+                DefPathData::CrateRoot => {
+                    assert!(key.parent.is_none());
+                    break;
+                }
+                DefPathData::InlinedRoot(ref p) => {
+                    assert!(key.parent.is_none());
+                    assert!(!p.def_id.is_local());
+                    data.extend(p.data.iter().cloned().rev());
+                    krate = p.def_id.krate;
+                    break;
+                }
+                _ => {
+                    data.push(key.disambiguated_data);
+                    index = key.parent;
+                }
+            }
+        }
+        data.reverse();
+        DefPath { data: data, krate: krate }
+    }
+}
+
 /// Root of an inlined item. We track the `DefPath` of the item within
 /// the original crate but also its def-id. This is kind of an
 /// augmented version of a `DefPath` that includes a `DefId`. This is
@@ -141,7 +188,7 @@ impl Definitions {
     /// will be the path of the item in the external crate (but the
     /// path will begin with the path to the external crate).
     pub fn def_path(&self, index: DefIndex) -> DefPath {
-        make_def_path(index, |p| self.def_key(p))
+        DefPath::make(LOCAL_CRATE, index, |p| self.def_key(p))
     }
 
     pub fn opt_def_index(&self, node: ast::NodeId) -> Option<DefIndex> {
@@ -247,29 +294,3 @@ impl DefPathData {
     }
 }
 
-pub fn make_def_path<FN>(start_index: DefIndex, mut get_key: FN) -> DefPath
-    where FN: FnMut(DefIndex) -> DefKey
-{
-    let mut result = vec![];
-    let mut index = Some(start_index);
-    while let Some(p) = index {
-        let key = get_key(p);
-        match key.disambiguated_data.data {
-            DefPathData::CrateRoot => {
-                assert!(key.parent.is_none());
-                break;
-            }
-            DefPathData::InlinedRoot(ref p) => {
-                assert!(key.parent.is_none());
-                result.extend(p.iter().cloned().rev());
-                break;
-            }
-            _ => {
-                result.push(key.disambiguated_data);
-                index = key.parent;
-            }
-        }
-    }
-    result.reverse();
-    result
-}

src/librustc/middle/ty/context.rs

@@ -15,7 +15,7 @@ use front::map as ast_map;
 use session::Session;
 use lint;
 use middle;
-use middle::cstore::CrateStore;
+use middle::cstore::{CrateStore, LOCAL_CRATE};
 use middle::def::DefMap;
 use middle::def_id::DefId;
 use middle::free_region::FreeRegionMap;
@@ -422,6 +422,22 @@ pub struct TyCtxt<'tcx> {
 }
 
 impl<'tcx> TyCtxt<'tcx> {
+    pub fn crate_name(&self, cnum: ast::CrateNum) -> token::InternedString {
+        if cnum == LOCAL_CRATE {
+            self.crate_name.clone()
+        } else {
+            self.sess.cstore.crate_name(cnum)
+        }
+    }
+
+    pub fn crate_disambiguator(&self, cnum: ast::CrateNum) -> token::InternedString {
+        if cnum == LOCAL_CRATE {
+            self.sess.crate_disambiguator.get().as_str()
+        } else {
+            self.sess.cstore.crate_name(cnum)
+        }
+    }
+
     pub fn type_parameter_def(&self,
                               node_id: NodeId)
                               -> ty::TypeParameterDef<'tcx>

src/librustc/session/mod.rs

@@ -24,6 +24,7 @@ use syntax::diagnostics;
 use syntax::feature_gate;
 use syntax::parse;
 use syntax::parse::ParseSess;
+use syntax::parse::token;
 use syntax::{ast, codemap};
 use syntax::feature_gate::AttributeType;
 
@@ -69,7 +70,7 @@ pub struct Session {
     // forms a unique global identifier for the crate. It is used to allow
     // multiple crates with the same name to coexist. See the
     // trans::back::symbol_names module for more information.
-    pub crate_disambiguator: RefCell<String>,
+    pub crate_disambiguator: Cell<ast::Name>,
     pub features: RefCell<feature_gate::Features>,
 
     /// The maximum recursion limit for potentially infinitely recursive
@@ -486,7 +487,7 @@ pub fn build_session_(sopts: config::Options,
         plugin_attributes: RefCell::new(Vec::new()),
         crate_types: RefCell::new(Vec::new()),
         dependency_formats: RefCell::new(FnvHashMap()),
-        crate_disambiguator: RefCell::new(String::new()),
+        crate_disambiguator: Cell::new(token::intern("")),
         features: RefCell::new(feature_gate::Features::new()),
         recursion_limit: Cell::new(64),
         next_node_id: Cell::new(1),

src/librustc_driver/driver.rs

@@ -501,7 +501,7 @@ pub fn phase_2_configure_and_expand(sess: &Session,
     })?;
 
     *sess.crate_types.borrow_mut() = collect_crate_types(sess, &krate.attrs);
-    *sess.crate_disambiguator.borrow_mut() = compute_crate_disambiguator(sess);
+    sess.crate_disambiguator.set(token::intern(&compute_crate_disambiguator(sess)));
 
     time(time_passes, "recursion limit", || {
         middle::recursion_limit::update_recursion_limit(sess, &krate);

src/librustc_metadata/creader.rs

@@ -284,7 +284,7 @@ impl<'a> CrateReader<'a> {
 
         // Check for (potential) conflicts with the local crate
         if self.local_crate_name == crate_name &&
-           &self.sess.crate_disambiguator.borrow()[..] == disambiguator {
+           self.sess.crate_disambiguator.get().as_str() == disambiguator {
             span_fatal!(self.sess, span, E0519,
                         "the current crate is indistinguishable from one of its \
                          dependencies: it has the same crate-name `{}` and was \

src/librustc_metadata/decoder.rs

@@ -1779,9 +1779,5 @@ fn def_key(item_doc: rbml::Doc) -> hir_map::DefKey {
 
 pub fn def_path(cdata: Cmd, id: DefIndex) -> hir_map::DefPath {
     debug!("def_path(id={:?})", id);
-    hir_map::definitions::make_def_path(id, |parent| {
-        debug!("def_path: parent={:?}", parent);
-        let parent_doc = cdata.lookup_item(parent);
-        def_key(parent_doc)
-    })
+    hir_map::DefPath::make(cdata.cnum, id, |parent| def_key(cdata, parent))
 }

src/librustc_metadata/encoder.rs

@@ -1991,7 +1991,7 @@ fn encode_metadata_inner(rbml_w: &mut Encoder,
     encode_crate_name(rbml_w, &ecx.link_meta.crate_name);
     encode_crate_triple(rbml_w, &ecx.tcx.sess.opts.target_triple);
     encode_hash(rbml_w, &ecx.link_meta.crate_hash);
-    encode_crate_disambiguator(rbml_w, &ecx.tcx.sess.crate_disambiguator.borrow());
+    encode_crate_disambiguator(rbml_w, &ecx.tcx.sess.crate_disambiguator.get().as_str());
     encode_dylib_dependency_formats(rbml_w, &ecx);
 
     let mut i = rbml_w.writer.seek(SeekFrom::Current(0)).unwrap();

src/librustc_trans/back/link.rs

@@ -130,7 +130,7 @@ pub fn build_link_meta(sess: &Session,
                        -> LinkMeta {
     let r = LinkMeta {
         crate_name: name.to_owned(),
-        crate_hash: Svh::calculate(&sess.crate_disambiguator.borrow()[..], krate),
+        crate_hash: Svh::calculate(&sess.crate_disambiguator.get().as_str(), krate),
     };
     info!("{:?}", r);
     return r;

src/librustc_trans/back/symbol_names.rs

@@ -111,23 +111,18 @@ use syntax::parse::token::{self, InternedString};
 use serialize::hex::ToHex;
 
 pub fn def_id_to_string<'tcx>(tcx: &ty::TyCtxt<'tcx>, def_id: DefId) -> String {
-
     let def_path = tcx.def_path(def_id);
-    let mut s = String::with_capacity(def_path.len() * 16);
+    def_path_to_string(tcx, &def_path)
+}
 
-    let def_path = if def_id.is_local() {
-        s.push_str(&tcx.crate_name[..]);
-        s.push_str("/");
-        s.push_str(&tcx.sess.crate_disambiguator.borrow()[..]);
-        &def_path[..]
-    } else {
-        s.push_str(&tcx.sess.cstore.crate_name(def_id.krate)[..]);
-        s.push_str("/");
-        s.push_str(&tcx.sess.cstore.crate_disambiguator(def_id.krate));
-        &def_path[1..]
-    };
+pub fn def_path_to_string<'tcx>(tcx: &ty::TyCtxt<'tcx>, def_path: &DefPath) -> String {
+    let mut s = String::with_capacity(def_path.data.len() * 16);
 
-    for component in def_path {
+    s.push_str(&tcx.crate_name(def_path.krate));
+    s.push_str("/");
+    s.push_str(&tcx.crate_disambiguator(def_path.krate));
+
+    for component in &def_path.data {
         write!(s,
                "::{}[{}]",
                component.data.as_interned_str(),

src/librustc_trans/trans/base.rs

@@ -2444,7 +2444,7 @@ pub fn exported_name<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
             if attr::contains_name(attrs, "no_mangle") {
                 // Don't mangle
                 let path = ccx.tcx().map.def_path_from_id(id);
-                path.last().unwrap().data.to_string()
+                path.data.last().unwrap().data.to_string()
             } else {
                 match weak_lang_items::link_name(attrs) {
                     Some(name) => name.to_string(),