Support Self used within impl blocks

This is simply a type reference so we can use the name resolver to resolve
Self as a type reference back to the Type used for the impl block.

Fixes #204

6 files changed, 68 insertions, 6 deletions

diff --git a/gcc/rust/resolve/rust-ast-resolve-item.h b/gcc/rust/resolve/rust-ast-resolve-item.h
index cc8e451..5ed98a9 100644
--- a/gcc/rust/resolve/rust-ast-resolve-item.h
+++ b/gcc/rust/resolve/rust-ast-resolve-item.h
@@ -115,8 +115,18 @@ public:
 
   void visit (AST::InherentImpl &impl_block)
   {
+    NodeId resolved_node = ResolveType::go (impl_block.get_type ().get (),
+					    impl_block.get_node_id ());
+    if (resolved_node == UNKNOWN_NODEID)
+      return;
+
+    resolver->get_type_scope ().insert (
+      "Self", resolved_node, impl_block.get_type ()->get_locus_slow ());
+
     for (auto &impl_item : impl_block.get_impl_items ())
       impl_item->accept_vis (*this);
+
+    resolver->get_type_scope ().peek ()->clear_name ("Self", resolved_node);
   }
 
 private:
diff --git a/gcc/rust/resolve/rust-ast-resolve-toplevel.h b/gcc/rust/resolve/rust-ast-resolve-toplevel.h
index 0ed838a..2e4e8e7 100644
--- a/gcc/rust/resolve/rust-ast-resolve-toplevel.h
+++ b/gcc/rust/resolve/rust-ast-resolve-toplevel.h
@@ -110,10 +110,6 @@ public:
 
   void visit (AST::InherentImpl &impl_block)
   {
-    if (!ResolveType::go (impl_block.get_type ().get (),
-			  impl_block.get_node_id ()))
-      return;
-
     for (auto &impl_item : impl_block.get_impl_items ())
       ResolveToplevelImplItem::go (impl_item.get (),
 				   impl_block.get_type ().get ());
diff --git a/gcc/rust/resolve/rust-ast-resolve-type.h b/gcc/rust/resolve/rust-ast-resolve-type.h
index 258524b..ec8ee87 100644
--- a/gcc/rust/resolve/rust-ast-resolve-type.h
+++ b/gcc/rust/resolve/rust-ast-resolve-type.h
@@ -28,14 +28,14 @@ namespace Resolver {
 class ResolveType : public ResolverBase
 {
 public:
-  static bool go (AST::Type *type, NodeId parent)
+  static NodeId go (AST::Type *type, NodeId parent)
   {
     ResolveType resolver (parent);
     type->accept_vis (resolver);
     if (!resolver.ok)
       rust_error_at (type->get_locus_slow (), "unresolved type");
 
-    return resolver.ok;
+    return resolver.resolved_node;
   };
 
   void visit (AST::BareFunctionType &fntype)
diff --git a/gcc/rust/resolve/rust-name-resolver.h b/gcc/rust/resolve/rust-name-resolver.h
index 5544f30..ea0e4f5 100644
--- a/gcc/rust/resolve/rust-name-resolver.h
+++ b/gcc/rust/resolve/rust-name-resolver.h
@@ -71,6 +71,19 @@ public:
     return true;
   }
 
+  void clear_name (std::string ident, NodeId id)
+  {
+    mappings.erase (ident);
+    for (auto &it : decls_within_rib)
+      {
+	if (it.first == id)
+	  {
+	    decls_within_rib.erase (it);
+	    break;
+	  }
+      }
+  }
+
   CrateNum get_crate_num () const { return crate_num; }
   NodeId get_node_id () const { return node_id; }
 
diff --git a/gcc/testsuite/rust.test/compilable/impl_block3.rs b/gcc/testsuite/rust.test/compilable/impl_block3.rs
new file mode 100644
index 0000000..3093a6c
--- /dev/null
+++ b/gcc/testsuite/rust.test/compilable/impl_block3.rs
@@ -0,0 +1,31 @@
+struct Point {
+    x: f64,
+    y: f64,
+}
+
+impl Point {
+    fn origin() -> Point {
+        Point { x: 0.0, y: 0.0 }
+    }
+
+    fn new(x: f64, y: f64) -> Point {
+        Point { x: x, y: y }
+    }
+}
+
+struct Rectangle {
+    p1: Point,
+    p2: Point,
+}
+
+impl Rectangle {
+    fn from(p1: Point, p2: Point) -> Self {
+        Self { p1, p2 }
+    }
+}
+
+fn main() {
+    let p1 = Point::origin();
+    let p2 = Point::new(3.0, 4.0);
+    let rect = Rectangle::from(p1, p2);
+}
diff --git a/gcc/testsuite/rust.test/compilable/self_type1.rs b/gcc/testsuite/rust.test/compilable/self_type1.rs
new file mode 100644
index 0000000..373d6dd
--- /dev/null
+++ b/gcc/testsuite/rust.test/compilable/self_type1.rs
@@ -0,0 +1,12 @@
+struct Foo(i32, bool);
+
+impl Foo {
+    fn new(a: i32, b: bool) -> Self {
+        Self(a, b)
+    }
+}
+
+fn main() {
+    let a;
+    a = Foo::new(1, true);
+}