Rollup merge of #73155 - marmeladema:save-analysis-various-fixes, r=Xanewok

save_analysis: better handle paths and functions signature

This should improve slightly some possible regressions due to hir rework.

r? @Xanewok

4 files changed, 142 insertions, 77 deletions

diff --git a/src/librustc_hir_pretty/lib.rs b/src/librustc_hir_pretty/lib.rs
index e642915b86a..da8956ccb4d 100644
--- a/src/librustc_hir_pretty/lib.rs
+++ b/src/librustc_hir_pretty/lib.rs
@@ -227,6 +227,28 @@ pub fn path_to_string(segment: &hir::Path<'_>) -> String {
     to_string(NO_ANN, |s| s.print_path(segment, false))
 }
 
+pub fn fn_to_string(
+    decl: &hir::FnDecl<'_>,
+    header: hir::FnHeader,
+    name: Option<Symbol>,
+    generics: &hir::Generics<'_>,
+    vis: &hir::Visibility<'_>,
+    arg_names: &[Ident],
+    body_id: Option<hir::BodyId>,
+) -> String {
+    to_string(NO_ANN, |s| s.print_fn(decl, header, name, generics, vis, arg_names, body_id))
+}
+
+pub fn enum_def_to_string(
+    enum_definition: &hir::EnumDef<'_>,
+    generics: &hir::Generics<'_>,
+    name: Symbol,
+    span: rustc_span::Span,
+    visibility: &hir::Visibility<'_>,
+) -> String {
+    to_string(NO_ANN, |s| s.print_enum_def(enum_definition, generics, name, span, visibility))
+}
+
 impl<'a> State<'a> {
     pub fn cbox(&mut self, u: usize) {
         self.s.cbox(u);
diff --git a/src/librustc_save_analysis/dump_visitor.rs b/src/librustc_save_analysis/dump_visitor.rs
index 489d38b00df..fbde6bfd9aa 100644
--- a/src/librustc_save_analysis/dump_visitor.rs
+++ b/src/librustc_save_analysis/dump_visitor.rs
@@ -20,7 +20,7 @@ use rustc_hir as hir;
 use rustc_hir::def::{DefKind as HirDefKind, Res};
 use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_hir::intravisit::{self, Visitor};
-use rustc_hir_pretty::{bounds_to_string, generic_params_to_string, ty_to_string};
+use rustc_hir_pretty::{bounds_to_string, fn_to_string, generic_params_to_string, ty_to_string};
 use rustc_middle::hir::map::Map;
 use rustc_middle::span_bug;
 use rustc_middle::ty::{self, DefIdTree, TyCtxt};
@@ -199,23 +199,23 @@ impl<'l, 'tcx> DumpVisitor<'l, 'tcx> {
         self.dumper.compilation_opts(data);
     }
 
-    fn write_sub_paths(&mut self, path: &'tcx hir::Path<'tcx>) {
-        for seg in path.segments {
+    fn write_segments(&mut self, segments: impl IntoIterator<Item = &'tcx hir::PathSegment<'tcx>>) {
+        for seg in segments {
             if let Some(data) = self.save_ctxt.get_path_segment_data(seg) {
                 self.dumper.dump_ref(data);
             }
         }
     }
 
+    fn write_sub_paths(&mut self, path: &'tcx hir::Path<'tcx>) {
+        self.write_segments(path.segments)
+    }
+
     // As write_sub_paths, but does not process the last ident in the path (assuming it
     // will be processed elsewhere). See note on write_sub_paths about global.
     fn write_sub_paths_truncated(&mut self, path: &'tcx hir::Path<'tcx>) {
         if let [segments @ .., _] = path.segments {
-            for seg in segments {
-                if let Some(data) = self.save_ctxt.get_path_segment_data(seg) {
-                    self.dumper.dump_ref(data);
-                }
-            }
+            self.write_segments(segments)
         }
     }
 
@@ -276,7 +276,8 @@ impl<'l, 'tcx> DumpVisitor<'l, 'tcx> {
                 }
                 v.process_generic_params(&generics, &method_data.qualname, hir_id);
 
-                method_data.value = crate::make_signature(&sig.decl, &generics);
+                method_data.value =
+                    fn_to_string(sig.decl, sig.header, Some(ident.name), generics, vis, &[], None);
                 method_data.sig = sig::method_signature(hir_id, ident, generics, sig, &v.save_ctxt);
 
                 v.dumper.dump_def(&access_from_vis!(v.save_ctxt, vis, hir_id), method_data);
@@ -643,7 +644,7 @@ impl<'l, 'tcx> DumpVisitor<'l, 'tcx> {
         self.nest_tables(map.local_def_id(item.hir_id), |v| {
             v.visit_ty(&typ);
             if let &Some(ref trait_ref) = trait_ref {
-                v.process_path(trait_ref.hir_ref_id, &trait_ref.path);
+                v.process_path(trait_ref.hir_ref_id, &hir::QPath::Resolved(None, &trait_ref.path));
             }
             v.process_generic_params(generics, "", item.hir_id);
             for impl_item in impl_items {
@@ -746,7 +747,7 @@ impl<'l, 'tcx> DumpVisitor<'l, 'tcx> {
         }
     }
 
-    fn dump_path_ref(&mut self, id: hir::HirId, path: &hir::Path<'tcx>) {
+    fn dump_path_ref(&mut self, id: hir::HirId, path: &hir::QPath<'tcx>) {
         let path_data = self.save_ctxt.get_path_data(id, path);
         if let Some(path_data) = path_data {
             self.dumper.dump_ref(path_data);
@@ -760,14 +761,30 @@ impl<'l, 'tcx> DumpVisitor<'l, 'tcx> {
         }
     }
 
-    fn process_path(&mut self, id: hir::HirId, path: &'tcx hir::Path<'tcx>) {
-        if self.span.filter_generated(path.span) {
+    fn process_path(&mut self, id: hir::HirId, path: &hir::QPath<'tcx>) {
+        let span = match path {
+            hir::QPath::Resolved(_, path) => path.span,
+            hir::QPath::TypeRelative(_, segment) => segment.ident.span,
+        };
+        if self.span.filter_generated(span) {
             return;
         }
         self.dump_path_ref(id, path);
 
         // Type arguments
-        for seg in path.segments {
+        let segments = match path {
+            hir::QPath::Resolved(ty, path) => {
+                if let Some(ty) = ty {
+                    self.visit_ty(ty);
+                }
+                path.segments
+            }
+            hir::QPath::TypeRelative(ty, segment) => {
+                self.visit_ty(ty);
+                std::slice::from_ref(*segment)
+            }
+        };
+        for seg in segments {
             if let Some(ref generic_args) = seg.args {
                 for arg in generic_args.args {
                     if let hir::GenericArg::Type(ref ty) = arg {
@@ -777,7 +794,9 @@ impl<'l, 'tcx> DumpVisitor<'l, 'tcx> {
             }
         }
 
-        self.write_sub_paths_truncated(path);
+        if let hir::QPath::Resolved(_, path) = path {
+            self.write_sub_paths_truncated(path);
+        }
     }
 
     fn process_struct_lit(
@@ -931,9 +950,7 @@ impl<'l, 'tcx> DumpVisitor<'l, 'tcx> {
         }
 
         for (id, ref path) in collector.collected_paths {
-            if let hir::QPath::Resolved(_, path) = path {
-                self.process_path(id, path);
-            }
+            self.process_path(id, path);
         }
     }
 
@@ -1135,7 +1152,10 @@ impl<'l, 'tcx> DumpVisitor<'l, 'tcx> {
     fn process_bounds(&mut self, bounds: hir::GenericBounds<'tcx>) {
         for bound in bounds {
             if let hir::GenericBound::Trait(ref trait_ref, _) = *bound {
-                self.process_path(trait_ref.trait_ref.hir_ref_id, &trait_ref.trait_ref.path)
+                self.process_path(
+                    trait_ref.trait_ref.hir_ref_id,
+                    &hir::QPath::Resolved(None, &trait_ref.trait_ref.path),
+                )
             }
         }
     }
@@ -1330,13 +1350,16 @@ impl<'l, 'tcx> Visitor<'tcx> for DumpVisitor<'l, 'tcx> {
     fn visit_ty(&mut self, t: &'tcx hir::Ty<'tcx>) {
         self.process_macro_use(t.span);
         match t.kind {
-            hir::TyKind::Path(hir::QPath::Resolved(_, path)) => {
+            hir::TyKind::Path(ref path) => {
                 if generated_code(t.span) {
                     return;
                 }
 
                 if let Some(id) = self.lookup_def_id(t.hir_id) {
-                    let sub_span = path.segments.last().unwrap().ident.span;
+                    let sub_span = match path {
+                        hir::QPath::Resolved(_, path) => path.segments.last().unwrap().ident.span,
+                        hir::QPath::TypeRelative(_, segment) => segment.ident.span,
+                    };
                     let span = self.span_from_span(sub_span);
                     self.dumper.dump_ref(Ref {
                         kind: RefKind::Type,
@@ -1345,8 +1368,10 @@ impl<'l, 'tcx> Visitor<'tcx> for DumpVisitor<'l, 'tcx> {
                     });
                 }
 
-                self.write_sub_paths_truncated(path);
-                intravisit::walk_path(self, path);
+                if let hir::QPath::Resolved(_, path) = path {
+                    self.write_sub_paths_truncated(path);
+                }
+                intravisit::walk_qpath(self, path, t.hir_id, t.span);
             }
             hir::TyKind::Array(ref ty, ref anon_const) => {
                 self.visit_ty(ty);
@@ -1355,6 +1380,10 @@ impl<'l, 'tcx> Visitor<'tcx> for DumpVisitor<'l, 'tcx> {
                     v.visit_expr(&map.body(anon_const.body).value)
                 });
             }
+            hir::TyKind::Def(item_id, _) => {
+                let item = self.tcx.hir().item(item_id.id);
+                self.nest_tables(self.tcx.hir().local_def_id(item_id.id), |v| v.visit_item(item));
+            }
             _ => intravisit::walk_ty(self, t),
         }
     }
@@ -1432,8 +1461,8 @@ impl<'l, 'tcx> Visitor<'tcx> for DumpVisitor<'l, 'tcx> {
         self.visit_expr(&arm.body);
     }
 
-    fn visit_path(&mut self, p: &'tcx hir::Path<'tcx>, id: hir::HirId) {
-        self.process_path(id, p);
+    fn visit_qpath(&mut self, path: &'tcx hir::QPath<'tcx>, id: hir::HirId, _: Span) {
+        self.process_path(id, path);
     }
 
     fn visit_stmt(&mut self, s: &'tcx hir::Stmt<'tcx>) {
diff --git a/src/librustc_save_analysis/lib.rs b/src/librustc_save_analysis/lib.rs
index 0341b542526..8a456c903ec 100644
--- a/src/librustc_save_analysis/lib.rs
+++ b/src/librustc_save_analysis/lib.rs
@@ -13,11 +13,11 @@ use rustc_ast::ast::{self};
 use rustc_ast::util::comments::strip_doc_comment_decoration;
 use rustc_ast_pretty::pprust::attribute_to_string;
 use rustc_hir as hir;
-use rustc_hir::def::{CtorOf, DefKind as HirDefKind, Res};
+use rustc_hir::def::{DefKind as HirDefKind, Res};
 use rustc_hir::def_id::{DefId, LOCAL_CRATE};
 use rustc_hir::intravisit::{self, Visitor};
 use rustc_hir::Node;
-use rustc_hir_pretty::ty_to_string;
+use rustc_hir_pretty::{enum_def_to_string, fn_to_string, ty_to_string};
 use rustc_middle::hir::map::Map;
 use rustc_middle::middle::cstore::ExternCrate;
 use rustc_middle::middle::privacy::AccessLevels;
@@ -135,7 +135,7 @@ impl<'l, 'tcx> SaveContext<'l, 'tcx> {
         let def_id = self.tcx.hir().local_def_id(item.hir_id).to_def_id();
         let qualname = format!("::{}", self.tcx.def_path_str(def_id));
         match item.kind {
-            hir::ForeignItemKind::Fn(ref decl, _, ref generics) => {
+            hir::ForeignItemKind::Fn(ref decl, arg_names, ref generics) => {
                 filter!(self.span_utils, item.ident.span);
 
                 Some(Data::DefData(Def {
@@ -144,7 +144,23 @@ impl<'l, 'tcx> SaveContext<'l, 'tcx> {
                     span: self.span_from_span(item.ident.span),
                     name: item.ident.to_string(),
                     qualname,
-                    value: make_signature(decl, generics),
+                    value: fn_to_string(
+                        decl,
+                        hir::FnHeader {
+                            // functions in extern block are implicitly unsafe
+                            unsafety: hir::Unsafety::Unsafe,
+                            // functions in extern block cannot be const
+                            constness: hir::Constness::NotConst,
+                            abi: self.tcx.hir().get_foreign_abi(item.hir_id),
+                            // functions in extern block cannot be async
+                            asyncness: hir::IsAsync::NotAsync,
+                        },
+                        Some(item.ident.name),
+                        generics,
+                        &item.vis,
+                        arg_names,
+                        None,
+                    ),
                     parent: None,
                     children: vec![],
                     decl_id: None,
@@ -191,7 +207,15 @@ impl<'l, 'tcx> SaveContext<'l, 'tcx> {
                     span: self.span_from_span(item.ident.span),
                     name: item.ident.to_string(),
                     qualname,
-                    value: make_signature(&sig.decl, generics),
+                    value: fn_to_string(
+                        sig.decl,
+                        sig.header,
+                        Some(item.ident.name),
+                        generics,
+                        &item.vis,
+                        &[],
+                        None,
+                    ),
                     parent: None,
                     children: vec![],
                     decl_id: None,
@@ -268,13 +292,12 @@ impl<'l, 'tcx> SaveContext<'l, 'tcx> {
                     attributes: lower_attributes(item.attrs.to_vec(), self),
                 }))
             }
-            hir::ItemKind::Enum(ref def, _) => {
+            hir::ItemKind::Enum(ref def, ref generics) => {
                 let name = item.ident.to_string();
                 let qualname = format!("::{}", self.tcx.def_path_str(def_id));
                 filter!(self.span_utils, item.ident.span);
-                let variants_str =
-                    def.variants.iter().map(|v| v.ident.to_string()).collect::<Vec<_>>().join(", ");
-                let value = format!("{}::{{{}}}", name, variants_str);
+                let value =
+                    enum_def_to_string(def, generics, item.ident.name, item.span, &item.vis);
                 Some(Data::DefData(Def {
                     kind: DefKind::Enum,
                     id: id_from_def_id(def_id),
@@ -579,7 +602,7 @@ impl<'l, 'tcx> SaveContext<'l, 'tcx> {
                     ref_id: def_id.or(decl_id).map(id_from_def_id).unwrap_or_else(null_id),
                 }))
             }
-            hir::ExprKind::Path(hir::QPath::Resolved(_, path)) => {
+            hir::ExprKind::Path(ref path) => {
                 self.get_path_data(expr.hir_id, path).map(Data::RefData)
             }
             _ => {
@@ -631,8 +654,12 @@ impl<'l, 'tcx> SaveContext<'l, 'tcx> {
         }
     }
 
-    pub fn get_path_data(&self, id: hir::HirId, path: &hir::Path<'_>) -> Option<Ref> {
-        path.segments.last().and_then(|seg| {
+    pub fn get_path_data(&self, id: hir::HirId, path: &hir::QPath<'_>) -> Option<Ref> {
+        let segment = match path {
+            hir::QPath::Resolved(_, path) => path.segments.last(),
+            hir::QPath::TypeRelative(_, segment) => Some(*segment),
+        };
+        segment.and_then(|seg| {
             self.get_path_segment_data(seg).or_else(|| self.get_path_segment_data_with_id(seg, id))
         })
     }
@@ -681,20 +708,16 @@ impl<'l, 'tcx> SaveContext<'l, 'tcx> {
             Res::Def(HirDefKind::ConstParam, def_id) => {
                 Some(Ref { kind: RefKind::Variable, span, ref_id: id_from_def_id(def_id) })
             }
-            Res::Def(HirDefKind::Ctor(CtorOf::Struct, ..), def_id) => {
-                // This is a reference to a tuple struct where the def_id points
+            Res::Def(HirDefKind::Ctor(_, ..), def_id) => {
+                // This is a reference to a tuple struct or an enum variant where the def_id points
                 // to an invisible constructor function. That is not a very useful
-                // def, so adjust to point to the tuple struct itself.
+                // def, so adjust to point to the tuple struct or enum variant itself.
                 let parent_def_id = self.tcx.parent(def_id).unwrap();
                 Some(Ref { kind: RefKind::Type, span, ref_id: id_from_def_id(parent_def_id) })
             }
-            Res::Def(
-                HirDefKind::Static
-                | HirDefKind::Const
-                | HirDefKind::AssocConst
-                | HirDefKind::Ctor(..),
-                _,
-            ) => Some(Ref { kind: RefKind::Variable, span, ref_id: id_from_def_id(res.def_id()) }),
+            Res::Def(HirDefKind::Static | HirDefKind::Const | HirDefKind::AssocConst, _) => {
+                Some(Ref { kind: RefKind::Variable, span, ref_id: id_from_def_id(res.def_id()) })
+            }
             Res::Def(HirDefKind::AssocFn, decl_id) => {
                 let def_id = if decl_id.is_local() {
                     let ti = self.tcx.associated_item(decl_id);
@@ -844,31 +867,6 @@ impl<'l, 'tcx> SaveContext<'l, 'tcx> {
     }
 }
 
-fn make_signature(decl: &hir::FnDecl<'_>, generics: &hir::Generics<'_>) -> String {
-    let mut sig = "fn ".to_owned();
-    if !generics.params.is_empty() {
-        sig.push('<');
-        sig.push_str(
-            &generics
-                .params
-                .iter()
-                .map(|param| param.name.ident().to_string())
-                .collect::<Vec<_>>()
-                .join(", "),
-        );
-        sig.push_str("> ");
-    }
-    sig.push('(');
-    sig.push_str(&decl.inputs.iter().map(ty_to_string).collect::<Vec<_>>().join(", "));
-    sig.push(')');
-    match decl.output {
-        hir::FnRetTy::DefaultReturn(_) => sig.push_str(" -> ()"),
-        hir::FnRetTy::Return(ref t) => sig.push_str(&format!(" -> {}", ty_to_string(t))),
-    }
-
-    sig
-}
-
 // An AST visitor for collecting paths (e.g., the names of structs) and formal
 // variables (idents) from patterns.
 struct PathCollector<'l> {
diff --git a/src/librustc_save_analysis/sig.rs b/src/librustc_save_analysis/sig.rs
index 6fec5cdba8b..5f337f5f770 100644
--- a/src/librustc_save_analysis/sig.rs
+++ b/src/librustc_save_analysis/sig.rs
@@ -281,6 +281,22 @@ impl<'hir> Sig for hir::Ty<'hir> {
                     })
                 }
             }
+            hir::TyKind::Path(hir::QPath::TypeRelative(ty, segment)) => {
+                let nested_ty = ty.make(offset + 1, id, scx)?;
+                let prefix = format!("<{}>::", nested_ty.text,);
+
+                let name = path_segment_to_string(segment);
+                let res = scx.get_path_res(id.ok_or("Missing id for Path")?);
+                let id = id_from_def_id(res.def_id());
+
+                let start = offset + prefix.len();
+                let end = start + name.len();
+                Ok(Signature {
+                    text: prefix + &name,
+                    defs: vec![],
+                    refs: vec![SigElement { id, start, end }],
+                })
+            }
             hir::TyKind::TraitObject(bounds, ..) => {
                 // FIXME recurse into bounds
                 let bounds: Vec<hir::GenericBound<'_>> = bounds
@@ -308,11 +324,11 @@ impl<'hir> Sig for hir::Ty<'hir> {
                 let text = format!("[{}; {}]", nested_ty.text, expr);
                 Ok(replace_text(nested_ty, text))
             }
-            hir::TyKind::Typeof(_)
-            | hir::TyKind::Infer
-            | hir::TyKind::Def(..)
-            | hir::TyKind::Path(..)
-            | hir::TyKind::Err => Err("Ty"),
+            hir::TyKind::Def(item_id, _) => {
+                let item = scx.tcx.hir().item(item_id.id);
+                item.make(offset, Some(item_id.id), scx)
+            }
+            hir::TyKind::Typeof(_) | hir::TyKind::Infer | hir::TyKind::Err => Err("Ty"),
         }
     }
 }