Rollup merge of #50399 - nrc:alias, r=eddyb

save-analysis: handle aliasing imports a bit more nicely

r? @eddyb

3 files changed, 55 insertions, 101 deletions

diff --git a/src/Cargo.lock b/src/Cargo.lock
index 2f52c889558..6103c77ec22 100644
--- a/src/Cargo.lock
+++ b/src/Cargo.lock
@@ -79,15 +79,15 @@ dependencies = [
 
 [[package]]
 name = "assert_cli"
-version = "0.5.6"
+version = "0.5.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "colored 1.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "difference 2.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "difference 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "environment 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "failure 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "failure_derive 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "error-chain 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_json 1.0.15 (registry+https://github.com/rust-lang/crates.io-index)",
+ "skeptic 0.13.3 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -184,6 +184,11 @@ name = "build_helper"
 version = "0.1.0"
 
 [[package]]
+name = "bytecount"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
 name = "byteorder"
 version = "1.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -572,6 +577,11 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "difference"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "difference"
 version = "2.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
@@ -1550,7 +1560,7 @@ dependencies = [
  "lazy_static 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.40 (registry+https://github.com/rust-lang/crates.io-index)",
  "num_cpus 1.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand 0.3.22 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -1690,6 +1700,15 @@ dependencies = [
 ]
 
 [[package]]
+name = "rls-data"
+version = "0.16.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rls-span 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-serialize 0.3.24 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "rls-rustc"
 version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -2140,7 +2159,7 @@ name = "rustc_save_analysis"
 version = "0.0.0"
 dependencies = [
  "log 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "rls-data 0.15.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rls-data 0.16.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rls-span 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc 0.0.0",
  "rustc-serialize 0.3.24 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2290,7 +2309,7 @@ dependencies = [
 name = "rustfmt-nightly"
 version = "0.6.1"
 dependencies = [
- "assert_cli 0.5.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "assert_cli 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "cargo_metadata 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "derive-new 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "diff 0.1.11 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2418,6 +2437,21 @@ version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "skeptic"
+version = "0.13.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "bytecount 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cargo_metadata 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "error-chain 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "glob 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
+ "pulldown-cmark 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_json 1.0.15 (registry+https://github.com/rust-lang/crates.io-index)",
+ "tempdir 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "walkdir 2.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "smallvec"
 version = "0.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -2988,7 +3022,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum ansi_term 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ee49baf6cb617b853aa8d93bf420db2383fab46d314482ca2803b40d5fde979b"
 "checksum ar 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "35c7a5669cb64f085739387e1308b74e6d44022464b7f1b63bbd4ceb6379ec31"
 "checksum arrayvec 0.4.7 (registry+https://github.com/rust-lang/crates.io-index)" = "a1e964f9e24d588183fcb43503abda40d288c8657dfc27311516ce2f05675aef"
-"checksum assert_cli 0.5.6 (registry+https://github.com/rust-lang/crates.io-index)" = "4c8ca6beaa44a3520407b28a4a779a19b1364fcadcb2f258c41a7baf3102ced0"
+"checksum assert_cli 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)" = "72342c21057a3cb5f7c2d849bf7999a83795434dd36d74fa8c24680581bd1930"
 "checksum atty 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)" = "af80143d6f7608d746df1520709e5d141c96f240b0e62b0aa41bdfb53374d9d4"
 "checksum backtrace 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)" = "ebbe525f66f42d207968308ee86bc2dd60aa5fab535b22e616323a173d097d8e"
 "checksum backtrace-sys 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)" = "44585761d6161b0f57afc49482ab6bd067e4edef48c12a152c237eb0203f7661"
@@ -2996,6 +3030,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum bitflags 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)" = "4efd02e230a02e18f92fc2735f44597385ed02ad8f831e7c1c1156ee5e1ab3a5"
 "checksum bitflags 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)" = "b3c30d3802dfb7281680d6285f2ccdaa8c2d8fee41f93805dba5c4cf50dc23cf"
 "checksum bufstream 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "f2f382711e76b9de6c744cc00d0497baba02fb00a787f088c879f01d09468e32"
+"checksum bytecount 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "882585cd7ec84e902472df34a5e01891202db3bf62614e1f0afe459c1afcf744"
 "checksum byteorder 1.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "73b5bdfe7ee3ad0b99c9801d58807a9dbc9e09196365b0203853b99889ab3c87"
 "checksum cargo_metadata 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)" = "6ebd6272a2ca4fd39dbabbd6611eb03df45c2259b3b80b39a9ff8fbdcf42a4b3"
 "checksum cc 1.0.15 (registry+https://github.com/rust-lang/crates.io-index)" = "0ebb87d1116151416c0cf66a0e3fb6430cccd120fd6300794b4dfaa050ac40ba"
@@ -3020,6 +3055,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum debug_unreachable 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "9a032eac705ca39214d169f83e3d3da290af06d8d1d344d1baad2fd002dca4b3"
 "checksum derive-new 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)" = "ceed73957c449214f8440eec8ad7fa282b67dc9eacbb24a3085b15d60397a17a"
 "checksum diff 0.1.11 (registry+https://github.com/rust-lang/crates.io-index)" = "3c2b69f912779fbb121ceb775d74d51e915af17aaebc38d28a592843a2dd0a3a"
+"checksum difference 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b3304d19798a8e067e48d8e69b2c37f0b5e9b4e462504ad9e27e9f3fce02bba8"
 "checksum difference 2.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "524cbf6897b527295dff137cec09ecf3a05f4fddffd7dfcd1585403449e74198"
 "checksum dtoa 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)" = "09c3753c3db574d215cba4ea76018483895d7bff25a31b49ba45db21c48e50ab"
 "checksum either 1.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3be565ca5c557d7f59e7cfcf1844f9e3033650c929c6566f511e8005f205c1d0"
@@ -3132,6 +3168,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum rls-analysis 0.12.1 (registry+https://github.com/rust-lang/crates.io-index)" = "a41488cf5dc99d6ce383319d2978756567b70d4ed0539eb0d9ce07763e732e46"
 "checksum rls-blacklist 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "e4a9cc2545ccb7e05b355bfe047b8039a6ec12270d5f3c996b766b340a50f7d2"
 "checksum rls-data 0.15.0 (registry+https://github.com/rust-lang/crates.io-index)" = "bea04462e94b5512a78499837eecb7db182ff082144cd1b4bc32ef5d43de6510"
+"checksum rls-data 0.16.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3dd20763e1c60ae8945384c8a8fa4ac44f8afa7b0a817511f5e8927e5d24f988"
 "checksum rls-rustc 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "885f66b92757420572cbb02e033d4a9558c7413ca9b7ac206f28fd58ffdb44ea"
 "checksum rls-span 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "5d7c7046dc6a92f2ae02ed302746db4382e75131b9ce20ce967259f6b5867a6a"
 "checksum rls-vfs 0.4.5 (registry+https://github.com/rust-lang/crates.io-index)" = "be231e1e559c315bc60ced5ad2cc2d7a9c208ed7d4e2c126500149836fda19bb"
@@ -3162,6 +3199,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum shell-escape 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)" = "170a13e64f2a51b77a45702ba77287f5c6829375b04a69cf2222acd17d0cfab9"
 "checksum shlex 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "7fdf1b9db47230893d76faad238fd6097fd6d6a9245cd7a4d90dbd639536bbd2"
 "checksum siphasher 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "0df90a788073e8d0235a67e50441d47db7c8ad9debd91cbf43736a2a92d36537"
+"checksum skeptic 0.13.3 (registry+https://github.com/rust-lang/crates.io-index)" = "c4474d6da9593171bcb086890fc344a3a12783cb24e5b141f8a5d0e43561f4b6"
 "checksum smallvec 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "44db0ecb22921ef790d17ae13a3f6d15784183ff5f2a01aa32098c7498d2b4b9"
 "checksum socket2 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)" = "ff606e0486e88f5fc6cfeb3966e434fb409abbc7a3ab495238f70a1ca97f789d"
 "checksum stable_deref_trait 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "15132e0e364248108c5e2c02e3ab539be8d6f5d52a01ca9bbf27ed657316f02b"
diff --git a/src/librustc_save_analysis/Cargo.toml b/src/librustc_save_analysis/Cargo.toml
index 976614c9542..7b94170ef6d 100644
--- a/src/librustc_save_analysis/Cargo.toml
+++ b/src/librustc_save_analysis/Cargo.toml
@@ -16,7 +16,7 @@ rustc_target = { path = "../librustc_target" }
 rustc_typeck = { path = "../librustc_typeck" }
 syntax = { path = "../libsyntax" }
 syntax_pos = { path = "../libsyntax_pos" }
-rls-data = "0.15"
+rls-data = "0.16"
 rls-span = "0.4"
 # FIXME(#40527) should move rustc serialize out of tree
 rustc-serialize = "0.3"
diff --git a/src/librustc_save_analysis/dump_visitor.rs b/src/librustc_save_analysis/dump_visitor.rs
index abaa02a856e..2ef294fe430 100644
--- a/src/librustc_save_analysis/dump_visitor.rs
+++ b/src/librustc_save_analysis/dump_visitor.rs
@@ -268,80 +268,6 @@ impl<'l, 'tcx: 'l, 'll, O: DumpOutput + 'll> DumpVisitor<'l, 'tcx, 'll, O> {
         }
     }
 
-    fn process_def_kind(
-        &mut self,
-        ref_id: NodeId,
-        span: Span,
-        sub_span: Option<Span>,
-        def_id: DefId,
-    ) {
-        if self.span.filter_generated(sub_span, span) {
-            return;
-        }
-
-        let def = self.save_ctxt.get_path_def(ref_id);
-        match def {
-            HirDef::Mod(_) => {
-                let span = self.span_from_span(sub_span.expect("No span found for mod ref"));
-                self.dumper.dump_ref(Ref {
-                    kind: RefKind::Mod,
-                    span,
-                    ref_id: ::id_from_def_id(def_id),
-                });
-            }
-            HirDef::Struct(..) |
-            HirDef::Variant(..) |
-            HirDef::Union(..) |
-            HirDef::Enum(..) |
-            HirDef::TyAlias(..) |
-            HirDef::TyForeign(..) |
-            HirDef::TraitAlias(..) |
-            HirDef::Trait(_) => {
-                let span = self.span_from_span(sub_span.expect("No span found for type ref"));
-                self.dumper.dump_ref(Ref {
-                    kind: RefKind::Type,
-                    span,
-                    ref_id: ::id_from_def_id(def_id),
-                });
-            }
-            HirDef::Static(..) |
-            HirDef::Const(..) |
-            HirDef::StructCtor(..) |
-            HirDef::VariantCtor(..) => {
-                let span = self.span_from_span(sub_span.expect("No span found for var ref"));
-                self.dumper.dump_ref(Ref {
-                    kind: RefKind::Variable,
-                    span,
-                    ref_id: ::id_from_def_id(def_id),
-                });
-            }
-            HirDef::Fn(..) => {
-                let span = self.span_from_span(sub_span.expect("No span found for fn ref"));
-                self.dumper.dump_ref(Ref {
-                    kind: RefKind::Function,
-                    span,
-                    ref_id: ::id_from_def_id(def_id),
-                });
-            }
-            // With macros 2.0, we can legitimately get a ref to a macro, but
-            // we don't handle it properly for now (FIXME).
-            HirDef::Macro(..) => {}
-            HirDef::Local(..) |
-            HirDef::Upvar(..) |
-            HirDef::SelfTy(..) |
-            HirDef::Label(_) |
-            HirDef::TyParam(..) |
-            HirDef::Method(..) |
-            HirDef::AssociatedTy(..) |
-            HirDef::AssociatedConst(..) |
-            HirDef::PrimTy(_) |
-            HirDef::GlobalAsm(_) |
-            HirDef::Err => {
-                span_bug!(span, "process_def_kind for unexpected item: {:?}", def);
-            }
-        }
-    }
-
     fn process_formals(&mut self, formals: &'l [ast::Arg], qualname: &str) {
         for arg in formals {
             self.visit_pat(&arg.pat);
@@ -1348,29 +1274,17 @@ impl<'l, 'tcx: 'l, 'll, O: DumpOutput + 'll> DumpVisitor<'l, 'tcx, 'll, O> {
                 };
 
                 let sub_span = self.span.span_for_last_ident(path.span);
-                let mod_id = match self.lookup_def_id(id) {
-                    Some(def_id) => {
-                        self.process_def_kind(id, path.span, sub_span, def_id);
-                        Some(def_id)
-                    }
-                    None => None,
-                };
-
-                // 'use' always introduces an alias, if there is not an explicit
-                // one, there is an implicit one.
-                let sub_span = match self.span.sub_span_after_keyword(use_tree.span,
-                                                                      keywords::As) {
-                    Some(sub_span) => Some(sub_span),
-                    None => sub_span,
-                };
+                let alias_span = self.span.sub_span_after_keyword(use_tree.span, keywords::As);
+                let ref_id = self.lookup_def_id(id);
 
                 if !self.span.filter_generated(sub_span, path.span) {
-                    let span =
-                        self.span_from_span(sub_span.expect("No span found for use"));
+                    let span = self.span_from_span(sub_span.expect("No span found for use"));
+                    let alias_span = alias_span.map(|sp| self.span_from_span(sp));
                     self.dumper.import(&access, Import {
                         kind: ImportKind::Use,
-                        ref_id: mod_id.map(|id| ::id_from_def_id(id)),
+                        ref_id: ref_id.map(|id| ::id_from_def_id(id)),
                         span,
+                        alias_span,
                         name: ident.to_string(),
                         value: String::new(),
                         parent,
@@ -1407,6 +1321,7 @@ impl<'l, 'tcx: 'l, 'll, O: DumpOutput + 'll> DumpVisitor<'l, 'tcx, 'll, O> {
                         kind: ImportKind::GlobUse,
                         ref_id: None,
                         span,
+                        alias_span: None,
                         name: "*".to_owned(),
                         value: names.join(", "),
                         parent,
@@ -1500,6 +1415,7 @@ impl<'l, 'tcx: 'l, 'll, O: DumpOutput + 'll> Visitor<'l> for DumpVisitor<'l, 'tc
                             kind: ImportKind::ExternCrate,
                             ref_id: None,
                             span,
+                            alias_span: None,
                             name: item.ident.to_string(),
                             value: String::new(),
                             parent,