Rename `Span::empty` to `Span::shrink_to_lo`, add `Span::shrink_to_hi`

22 files changed, 38 insertions, 31 deletions

diff --git a/src/librustc/hir/lowering.rs b/src/librustc/hir/lowering.rs
index dd3b9350d91..1439410f7e9 100644
--- a/src/librustc/hir/lowering.rs
+++ b/src/librustc/hir/lowering.rs
@@ -879,7 +879,7 @@ impl<'a> LoweringContext<'a> {
             TyKind::Slice(ref ty) => hir::TySlice(self.lower_ty(ty, itctx)),
             TyKind::Ptr(ref mt) => hir::TyPtr(self.lower_mt(mt, itctx)),
             TyKind::Rptr(ref region, ref mt) => {
-                let span = t.span.with_hi(t.span.lo());
+                let span = t.span.shrink_to_lo();
                 let lifetime = match *region {
                     Some(ref lt) => self.lower_lifetime(lt),
                     None => self.elided_lifetime(span)
diff --git a/src/librustc_allocator/expand.rs b/src/librustc_allocator/expand.rs
index c088458c355..02e704b6841 100644
--- a/src/librustc_allocator/expand.rs
+++ b/src/librustc_allocator/expand.rs
@@ -99,7 +99,7 @@ impl<'a> Folder for ExpandAllocatorDirectives<'a> {
             f.cx.item_extern_crate(f.span, f.alloc),
             f.cx.item_use_simple(
                 f.span,
-                respan(f.span.empty(), VisibilityKind::Inherited),
+                respan(f.span.shrink_to_lo(), VisibilityKind::Inherited),
                 super_path,
             ),
         ];
diff --git a/src/librustc_lint/builtin.rs b/src/librustc_lint/builtin.rs
index 031033f7208..bffa8628ff3 100644
--- a/src/librustc_lint/builtin.rs
+++ b/src/librustc_lint/builtin.rs
@@ -1082,7 +1082,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for InvalidNoMangleItems {
                     if !cx.access_levels.is_reachable(it.id) {
                         let msg = "function is marked #[no_mangle], but not exported";
                         let mut err = cx.struct_span_lint(PRIVATE_NO_MANGLE_FNS, it.span, msg);
-                        let insertion_span = it.span.with_hi(it.span.lo());
+                        let insertion_span = it.span.shrink_to_lo();
                         if it.vis == hir::Visibility::Inherited {
                             err.span_suggestion(insertion_span,
                                                 "try making it public",
@@ -1107,7 +1107,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for InvalidNoMangleItems {
                    !cx.access_levels.is_reachable(it.id) {
                        let msg = "static is marked #[no_mangle], but not exported";
                        let mut err = cx.struct_span_lint(PRIVATE_NO_MANGLE_STATICS, it.span, msg);
-                       let insertion_span = it.span.with_hi(it.span.lo());
+                       let insertion_span = it.span.shrink_to_lo();
                        if it.vis == hir::Visibility::Inherited {
                            err.span_suggestion(insertion_span,
                                                "try making it public",
diff --git a/src/librustc_metadata/cstore_impl.rs b/src/librustc_metadata/cstore_impl.rs
index 0b50f5c4496..30ff03a2653 100644
--- a/src/librustc_metadata/cstore_impl.rs
+++ b/src/librustc_metadata/cstore_impl.rs
@@ -523,7 +523,7 @@ impl CrateStore for cstore::CStore {
                 tokens: body.into(),
                 legacy: def.legacy,
             }),
-            vis: codemap::respan(local_span.empty(), ast::VisibilityKind::Inherited),
+            vis: codemap::respan(local_span.shrink_to_lo(), ast::VisibilityKind::Inherited),
             tokens: None,
         })
     }
diff --git a/src/librustc_mir/build/mod.rs b/src/librustc_mir/build/mod.rs
index 23c5499bb63..8494c043f90 100644
--- a/src/librustc_mir/build/mod.rs
+++ b/src/librustc_mir/build/mod.rs
@@ -422,7 +422,7 @@ fn construct_fn<'a, 'gcx, 'tcx, A>(hir: Cx<'a, 'gcx, 'tcx>,
             builder.args_and_body(block, &arguments, arg_scope, &body.value)
         }));
         // Attribute epilogue to function's closing brace
-        let fn_end = span.with_lo(span.hi());
+        let fn_end = span.shrink_to_hi();
         let source_info = builder.source_info(fn_end);
         let return_block = builder.return_block();
         builder.cfg.terminate(block, source_info,
diff --git a/src/librustc_resolve/lib.rs b/src/librustc_resolve/lib.rs
index 23ad27ec2c3..dc22c23271d 100644
--- a/src/librustc_resolve/lib.rs
+++ b/src/librustc_resolve/lib.rs
@@ -756,7 +756,7 @@ impl<'tcx> Visitor<'tcx> for UsePlacementFinder {
                     // don't suggest placing a use before the prelude
                     // import or other generated ones
                     if item.span.ctxt().outer().expn_info().is_none() {
-                        self.span = Some(item.span.with_hi(item.span.lo()));
+                        self.span = Some(item.span.shrink_to_lo());
                         self.found_use = true;
                         return;
                     }
@@ -768,12 +768,12 @@ impl<'tcx> Visitor<'tcx> for UsePlacementFinder {
                     if item.span.ctxt().outer().expn_info().is_none() {
                         // don't insert between attributes and an item
                         if item.attrs.is_empty() {
-                            self.span = Some(item.span.with_hi(item.span.lo()));
+                            self.span = Some(item.span.shrink_to_lo());
                         } else {
                             // find the first attribute on the item
                             for attr in &item.attrs {
                                 if self.span.map_or(true, |span| attr.span < span) {
-                                    self.span = Some(attr.span.with_hi(attr.span.lo()));
+                                    self.span = Some(attr.span.shrink_to_lo());
                                 }
                             }
                         }
diff --git a/src/librustc_save_analysis/dump_visitor.rs b/src/librustc_save_analysis/dump_visitor.rs
index b9b4186c818..3d4d8571c6e 100644
--- a/src/librustc_save_analysis/dump_visitor.rs
+++ b/src/librustc_save_analysis/dump_visitor.rs
@@ -1209,7 +1209,7 @@ impl<'l, 'tcx: 'l, 'll, O: DumpOutput + 'll> DumpVisitor<'l, 'tcx, 'll, O> {
 
     fn process_trait_item(&mut self, trait_item: &'l ast::TraitItem, trait_id: DefId) {
         self.process_macro_use(trait_item.span);
-        let vis_span = trait_item.span.empty();
+        let vis_span = trait_item.span.shrink_to_lo();
         match trait_item.node {
             ast::TraitItemKind::Const(ref ty, ref expr) => {
                 self.process_assoc_const(
diff --git a/src/librustc_typeck/check/method/suggest.rs b/src/librustc_typeck/check/method/suggest.rs
index 5c20490f823..61afac97d64 100644
--- a/src/librustc_typeck/check/method/suggest.rs
+++ b/src/librustc_typeck/check/method/suggest.rs
@@ -767,7 +767,7 @@ impl<'a, 'tcx, 'gcx> hir::intravisit::Visitor<'tcx> for UsePlacementFinder<'a, '
                     // don't suggest placing a use before the prelude
                     // import or other generated ones
                     if item.span.ctxt().outer().expn_info().is_none() {
-                        self.span = Some(item.span.with_hi(item.span.lo()));
+                        self.span = Some(item.span.shrink_to_lo());
                         self.found_use = true;
                         return;
                     }
@@ -779,12 +779,12 @@ impl<'a, 'tcx, 'gcx> hir::intravisit::Visitor<'tcx> for UsePlacementFinder<'a, '
                     if item.span.ctxt().outer().expn_info().is_none() {
                         // don't insert between attributes and an item
                         if item.attrs.is_empty() {
-                            self.span = Some(item.span.with_hi(item.span.lo()));
+                            self.span = Some(item.span.shrink_to_lo());
                         } else {
                             // find the first attribute on the item
                             for attr in &item.attrs {
                                 if self.span.map_or(true, |span| attr.span < span) {
-                                    self.span = Some(attr.span.with_hi(attr.span.lo()));
+                                    self.span = Some(attr.span.shrink_to_lo());
                                 }
                             }
                         }
diff --git a/src/librustc_typeck/check/mod.rs b/src/librustc_typeck/check/mod.rs
index dc9455487ed..4a685cfddb7 100644
--- a/src/librustc_typeck/check/mod.rs
+++ b/src/librustc_typeck/check/mod.rs
@@ -2520,7 +2520,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
             if sugg_unit {
                 let sugg_span = sess.codemap().end_point(expr_sp);
                 // remove closing `)` from the span
-                let sugg_span = sugg_span.with_hi(sugg_span.lo());
+                let sugg_span = sugg_span.shrink_to_lo();
                 err.span_suggestion(
                     sugg_span,
                     "expected the unit value `()`; create it with empty parentheses",
diff --git a/src/libsyntax/ast.rs b/src/libsyntax/ast.rs
index 4ce6c53d338..eef7a6f8b4d 100644
--- a/src/libsyntax/ast.rs
+++ b/src/libsyntax/ast.rs
@@ -117,7 +117,7 @@ impl Path {
                 return None;
             }
         }
-        Some(PathSegment::crate_root(self.span.with_hi(self.span.lo())))
+        Some(PathSegment::crate_root(self.span.shrink_to_lo()))
     }
 
     pub fn is_global(&self) -> bool {
diff --git a/src/libsyntax/diagnostics/plugin.rs b/src/libsyntax/diagnostics/plugin.rs
index e8c2d325bd6..97cb6b492d7 100644
--- a/src/libsyntax/diagnostics/plugin.rs
+++ b/src/libsyntax/diagnostics/plugin.rs
@@ -220,7 +220,7 @@ pub fn expand_build_diagnostic_array<'cx>(ecx: &'cx mut ExtCtxt,
                 ty,
                 expr,
             ),
-            vis: codemap::respan(span.empty(), ast::VisibilityKind::Public),
+            vis: codemap::respan(span.shrink_to_lo(), ast::VisibilityKind::Public),
             span,
             tokens: None,
         })
diff --git a/src/libsyntax/ext/build.rs b/src/libsyntax/ext/build.rs
index ee646dc9174..9b53553bf69 100644
--- a/src/libsyntax/ext/build.rs
+++ b/src/libsyntax/ext/build.rs
@@ -987,7 +987,7 @@ impl<'a> AstBuilder for ExtCtxt<'a> {
             attrs,
             id: ast::DUMMY_NODE_ID,
             node,
-            vis: respan(span.empty(), ast::VisibilityKind::Inherited),
+            vis: respan(span.shrink_to_lo(), ast::VisibilityKind::Inherited),
             span,
             tokens: None,
         })
@@ -1033,7 +1033,7 @@ impl<'a> AstBuilder for ExtCtxt<'a> {
                 span: ty.span,
                 ty,
                 ident: None,
-                vis: respan(span.empty(), ast::VisibilityKind::Inherited),
+                vis: respan(span.shrink_to_lo(), ast::VisibilityKind::Inherited),
                 attrs: Vec::new(),
                 id: ast::DUMMY_NODE_ID,
             }
diff --git a/src/libsyntax/ext/expand.rs b/src/libsyntax/ext/expand.rs
index 7ccace014d0..34dd7696168 100644
--- a/src/libsyntax/ext/expand.rs
+++ b/src/libsyntax/ext/expand.rs
@@ -239,7 +239,7 @@ impl<'a, 'b> MacroExpander<'a, 'b> {
             node: ast::ItemKind::Mod(krate.module),
             ident: keywords::Invalid.ident(),
             id: ast::DUMMY_NODE_ID,
-            vis: respan(krate.span.empty(), ast::VisibilityKind::Public),
+            vis: respan(krate.span.shrink_to_lo(), ast::VisibilityKind::Public),
             tokens: None,
         })));
 
diff --git a/src/libsyntax/ext/quote.rs b/src/libsyntax/ext/quote.rs
index 7a024dbad88..b322fd9df3e 100644
--- a/src/libsyntax/ext/quote.rs
+++ b/src/libsyntax/ext/quote.rs
@@ -858,7 +858,7 @@ fn expand_wrapper(cx: &ExtCtxt,
         let path = path.iter().map(|s| s.to_string()).collect();
         let use_item = cx.item_use_glob(
             sp,
-            respan(sp.empty(), ast::VisibilityKind::Inherited),
+            respan(sp.shrink_to_lo(), ast::VisibilityKind::Inherited),
             ids_ext(path),
         );
         cx.stmt_item(sp, use_item)
diff --git a/src/libsyntax/fold.rs b/src/libsyntax/fold.rs
index 146f580e04e..46e6027b094 100644
--- a/src/libsyntax/fold.rs
+++ b/src/libsyntax/fold.rs
@@ -1019,7 +1019,7 @@ pub fn noop_fold_crate<T: Folder>(Crate {module, attrs, span}: Crate,
         ident: keywords::Invalid.ident(),
         attrs,
         id: ast::DUMMY_NODE_ID,
-        vis: respan(span.empty(), ast::VisibilityKind::Public),
+        vis: respan(span.shrink_to_lo(), ast::VisibilityKind::Public),
         span,
         node: ast::ItemKind::Mod(module),
         tokens: None,
diff --git a/src/libsyntax/parse/lexer/mod.rs b/src/libsyntax/parse/lexer/mod.rs
index 815ba49a60a..5b8887f3536 100644
--- a/src/libsyntax/parse/lexer/mod.rs
+++ b/src/libsyntax/parse/lexer/mod.rs
@@ -214,7 +214,7 @@ impl<'a> StringReader<'a> {
 
         // Make the range zero-length if the span is invalid.
         if span.lo() > span.hi() || begin.fm.start_pos != end.fm.start_pos {
-            span = span.with_hi(span.lo());
+            span = span.shrink_to_lo();
         }
 
         let mut sr = StringReader::new_raw_internal(sess, begin.fm);
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index ca879765b4e..cb7f165dbd4 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -1512,7 +1512,7 @@ impl<'a> Parser<'a> {
         if self.eat(&token::RArrow) {
             Ok(FunctionRetTy::Ty(self.parse_ty_common(allow_plus, true)?))
         } else {
-            Ok(FunctionRetTy::Default(self.span.with_hi(self.span.lo())))
+            Ok(FunctionRetTy::Default(self.span.shrink_to_lo()))
         }
     }
 
diff --git a/src/libsyntax/print/pprust.rs b/src/libsyntax/print/pprust.rs
index 319a9a3bbae..e6ed6d7b84a 100644
--- a/src/libsyntax/print/pprust.rs
+++ b/src/libsyntax/print/pprust.rs
@@ -1568,7 +1568,7 @@ impl<'a> State<'a> {
                     ti.ident,
                     ty,
                     default.as_ref().map(|expr| &**expr),
-                    &codemap::respan(ti.span.empty(), ast::VisibilityKind::Inherited),
+                    &codemap::respan(ti.span.shrink_to_lo(), ast::VisibilityKind::Inherited),
                 )?;
             }
             ast::TraitItemKind::Method(ref sig, ref body) => {
@@ -1579,7 +1579,7 @@ impl<'a> State<'a> {
                     ti.ident,
                     &ti.generics,
                     sig,
-                    &codemap::respan(ti.span.empty(), ast::VisibilityKind::Inherited),
+                    &codemap::respan(ti.span.shrink_to_lo(), ast::VisibilityKind::Inherited),
                 )?;
                 if let Some(ref body) = *body {
                     self.nbsp()?;
diff --git a/src/libsyntax/std_inject.rs b/src/libsyntax/std_inject.rs
index 401183e7c7d..fdbc795b2d3 100644
--- a/src/libsyntax/std_inject.rs
+++ b/src/libsyntax/std_inject.rs
@@ -76,7 +76,7 @@ pub fn maybe_inject_crates_ref(mut krate: ast::Crate, alt_std_name: Option<&str>
             is_sugared_doc: false,
             span,
         }],
-        vis: respan(span.empty(), ast::VisibilityKind::Inherited),
+        vis: respan(span.shrink_to_lo(), ast::VisibilityKind::Inherited),
         node: ast::ItemKind::Use(P(ast::UseTree {
             prefix: ast::Path {
                 segments: [name, "prelude", "v1"].into_iter().map(|name| {
diff --git a/src/libsyntax_ext/deriving/generic/mod.rs b/src/libsyntax_ext/deriving/generic/mod.rs
index 1b3917efdd1..49c372b751b 100644
--- a/src/libsyntax_ext/deriving/generic/mod.rs
+++ b/src/libsyntax_ext/deriving/generic/mod.rs
@@ -530,7 +530,7 @@ impl<'a> TraitDef<'a> {
                 id: ast::DUMMY_NODE_ID,
                 span: self.span,
                 ident,
-                vis: respan(self.span.empty(), ast::VisibilityKind::Inherited),
+                vis: respan(self.span.shrink_to_lo(), ast::VisibilityKind::Inherited),
                 defaultness: ast::Defaultness::Final,
                 attrs: Vec::new(),
                 generics: Generics::default(),
@@ -977,7 +977,7 @@ impl<'a> MethodDef<'a> {
             attrs: self.attributes.clone(),
             generics: fn_generics,
             span: trait_.span,
-            vis: respan(trait_.span.empty(), ast::VisibilityKind::Inherited),
+            vis: respan(trait_.span.shrink_to_lo(), ast::VisibilityKind::Inherited),
             defaultness: ast::Defaultness::Final,
             ident: method_ident,
             node: ast::ImplItemKind::Method(ast::MethodSig {
diff --git a/src/libsyntax_ext/global_asm.rs b/src/libsyntax_ext/global_asm.rs
index 9605f6b5c5a..f01a0aacb0a 100644
--- a/src/libsyntax_ext/global_asm.rs
+++ b/src/libsyntax_ext/global_asm.rs
@@ -60,7 +60,7 @@ pub fn expand_global_asm<'cx>(cx: &'cx mut ExtCtxt,
             asm,
             ctxt: cx.backtrace(),
         })),
-        vis: respan(sp.empty(), ast::VisibilityKind::Inherited),
+        vis: respan(sp.shrink_to_lo(), ast::VisibilityKind::Inherited),
         span: sp,
         tokens: None,
     })))
diff --git a/src/libsyntax_pos/lib.rs b/src/libsyntax_pos/lib.rs
index 4711d43bfab..9b83d5510fb 100644
--- a/src/libsyntax_pos/lib.rs
+++ b/src/libsyntax_pos/lib.rs
@@ -239,8 +239,15 @@ impl Span {
 
     /// Returns a new span representing an empty span at the beginning of this span
     #[inline]
-    pub fn empty(self) -> Span {
-        self.with_hi(self.lo())
+    pub fn shrink_to_lo(self) -> Span {
+        let span = self.data();
+        span.with_hi(span.lo)
+    }
+    /// Returns a new span representing an empty span at the end of this span
+    #[inline]
+    pub fn shrink_to_hi(self) -> Span {
+        let span = self.data();
+        span.with_lo(span.hi)
     }
 
     /// Returns `self` if `self` is not the dummy span, and `other` otherwise.