Record semantic types for all syntactic types in bodies

Author: petrochenkov

src/librustc_typeck/astconv.rs

@@ -76,6 +76,8 @@ pub trait AstConv<'gcx, 'tcx> {
     /// used to help suppress derived errors typeck might otherwise
     /// report.
     fn set_tainted_by_errors(&self);
+
+    fn record_ty(&self, hir_id: hir::HirId, ty: Ty<'tcx>, span: Span);
 }
 
 struct ConvertedBinding<'tcx> {
@@ -975,6 +977,14 @@ impl<'o, 'gcx: 'tcx, 'tcx> AstConv<'gcx, 'tcx>+'o {
                 }
             }
             Def::Err => {
+                for segment in &path.segments {
+                    for ty in &segment.parameters.types {
+                        self.ast_ty_to_ty(ty);
+                    }
+                    for binding in &segment.parameters.bindings {
+                        self.ast_ty_to_ty(&binding.ty);
+                    }
+                }
                 self.set_tainted_by_errors();
                 return self.tcx().types.err;
             }
@@ -1115,6 +1125,7 @@ impl<'o, 'gcx: 'tcx, 'tcx> AstConv<'gcx, 'tcx>+'o {
             }
         };
 
+        self.record_ty(ast_ty.hir_id, result_ty, ast_ty.span);
         result_ty
     }
 
@@ -1124,8 +1135,10 @@ impl<'o, 'gcx: 'tcx, 'tcx> AstConv<'gcx, 'tcx>+'o {
                      -> Ty<'tcx>
     {
         match ty.node {
-            hir::TyInfer if expected_ty.is_some() => expected_ty.unwrap(),
-            hir::TyInfer => self.ty_infer(ty.span),
+            hir::TyInfer if expected_ty.is_some() => {
+                self.record_ty(ty.hir_id, expected_ty.unwrap(), ty.span);
+                expected_ty.unwrap()
+            }
             _ => self.ast_ty_to_ty(ty),
         }
     }
@@ -1214,19 +1227,22 @@ impl<'o, 'gcx: 'tcx, 'tcx> AstConv<'gcx, 'tcx>+'o {
 
         let expected_ret_ty = expected_sig.as_ref().map(|e| e.output());
 
-        let is_infer = match decl.output {
-            hir::Return(ref output) if output.node == hir::TyInfer => true,
-            hir::DefaultReturn(..) => true,
-            _ => false
-        };
-
         let output_ty = match decl.output {
-            _ if is_infer && expected_ret_ty.is_some() =>
-                expected_ret_ty.unwrap(),
-            _ if is_infer => self.ty_infer(decl.output.span()),
-            hir::Return(ref output) =>
-                self.ast_ty_to_ty(&output),
-            hir::DefaultReturn(..) => bug!(),
+            hir::Return(ref output) => {
+                if let (&hir::TyInfer, Some(expected_ret_ty)) = (&output.node, expected_ret_ty) {
+                    self.record_ty(output.hir_id, expected_ret_ty, output.span);
+                    expected_ret_ty
+                } else {
+                    self.ast_ty_to_ty(&output)
+                }
+            }
+            hir::DefaultReturn(span) => {
+                if let Some(expected_ret_ty) = expected_ret_ty {
+                    expected_ret_ty
+                } else {
+                    self.ty_infer(span)
+                }
+            }
         };
 
         debug!("ty_of_closure: output_ty={:?}", output_ty);

src/librustc_typeck/check/mod.rs

@@ -1665,6 +1665,10 @@ impl<'a, 'gcx, 'tcx> AstConv<'gcx, 'tcx> for FnCtxt<'a, 'gcx, 'tcx> {
     fn set_tainted_by_errors(&self) {
         self.infcx.set_tainted_by_errors()
     }
+
+    fn record_ty(&self, hir_id: hir::HirId, ty: Ty<'tcx>, _span: Span) {
+        self.write_ty(hir_id, ty)
+    }
 }
 
 /// Controls whether the arguments are tupled. This is used for the call

src/librustc_typeck/check/writeback.rs

@@ -207,6 +207,13 @@ impl<'cx, 'gcx, 'tcx> Visitor<'gcx> for WritebackCx<'cx, 'gcx, 'tcx> {
         let var_ty = self.resolve(&var_ty, &l.span);
         self.write_ty_to_tables(l.hir_id, var_ty);
     }
+
+    fn visit_ty(&mut self, hir_ty: &'gcx hir::Ty) {
+        intravisit::walk_ty(self, hir_ty);
+        let ty = self.fcx.node_ty(hir_ty.hir_id);
+        let ty = self.resolve(&ty, &hir_ty.span);
+        self.write_ty_to_tables(hir_ty.hir_id, ty);
+    }
 }
 
 impl<'cx, 'gcx, 'tcx> WritebackCx<'cx, 'gcx, 'tcx> {

src/librustc_typeck/collect.rs

@@ -221,6 +221,10 @@ impl<'a, 'tcx> AstConv<'tcx, 'tcx> for ItemCtxt<'a, 'tcx> {
     fn set_tainted_by_errors(&self) {
         // no obvious place to track this, just let it go
     }
+
+    fn record_ty(&self, _hir_id: hir::HirId, _ty: Ty<'tcx>, _span: Span) {
+        // no place to record types from signatures?
+    }
 }
 
 fn type_param_predicates<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,

src/test/compile-fail/type-path-err-node-types.rs

@@ -0,0 +1,17 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// Type arguments of unresolved types should have their types recorded
+
+fn main() {
+    let _: Nonexistent<u8, Assoc = u16>; //~ ERROR cannot find type `Nonexistent` in this scope
+
+    let _ = |a, b: _| -> _ { 0 };
+}