1 files changed, 171 insertions, 0 deletions
diff --git a/gcc/rust/ast/rust-ast-fragment.cc b/gcc/rust/ast/rust-ast-fragment.cc
new file mode 100644
index 0000000..c491609
--- /dev/null
+++ b/gcc/rust/ast/rust-ast-fragment.cc
@@ -0,0 +1,171 @@
+// Copyright (C) 2020-2022 Free Software Foundation, Inc.
+
+// This file is part of GCC.
+
+// GCC is free software; you can redistribute it and/or modify it under
+// the terms of the GNU General Public License as published by the Free
+// Software Foundation; either version 3, or (at your option) any later
+// version.
+
+// GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+// WARRANTY; without even the implied warranty of MERCHANTABILITY or
+// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+// for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with GCC; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+#include "rust-ast-fragment.h"
+
+namespace Rust {
+namespace AST {
+
+Fragment::Fragment (FragmentKind kind, std::vector<SingleASTNode> nodes)
+  : kind (kind), nodes (std::move (nodes))
+{}
+
+Fragment::Fragment (Fragment const &other) : kind (other.get_kind ())
+{
+  *this = other;
+}
+
+Fragment &
+Fragment::operator= (Fragment const &other)
+{
+  nodes.clear ();
+  nodes.reserve (other.nodes.size ());
+  kind = other.get_kind ();
+  for (auto &n : other.nodes)
+    {
+      nodes.push_back (n);
+    }
+
+  return *this;
+}
+
+Fragment
+Fragment::create_error ()
+{
+  return Fragment (FragmentKind::Error, {});
+}
+
+Fragment
+Fragment::complete (std::vector<AST::SingleASTNode> nodes)
+{
+  return Fragment (FragmentKind::Complete, std::move (nodes));
+}
+
+Fragment
+Fragment::unexpanded ()
+{
+  return Fragment (FragmentKind::Unexpanded, {});
+}
+
+std::vector<SingleASTNode> &
+Fragment::get_nodes ()
+{
+  return nodes;
+}
+
+FragmentKind
+Fragment::get_kind () const
+{
+  return kind;
+}
+
+bool
+Fragment::is_error () const
+{
+  return get_kind () == FragmentKind::Error;
+}
+
+bool
+Fragment::should_expand () const
+{
+  return !is_error ();
+}
+
+bool
+Fragment::is_expression_fragment () const
+{
+  return is_single_fragment_of_kind (SingleASTNode::NodeType::EXPRESSION);
+}
+
+bool
+Fragment::is_type_fragment () const
+{
+  return is_single_fragment_of_kind (SingleASTNode::NodeType::TYPE);
+}
+
+std::unique_ptr<Expr>
+Fragment::take_expression_fragment ()
+{
+  assert_single_fragment (SingleASTNode::NodeType::EXPRESSION);
+  return nodes[0].take_expr ();
+}
+
+std::unique_ptr<Type>
+Fragment::take_type_fragment ()
+{
+  assert_single_fragment (SingleASTNode::NodeType::TYPE);
+  return nodes[0].take_type ();
+}
+
+void
+Fragment::accept_vis (ASTVisitor &vis)
+{
+  for (auto &node : nodes)
+    node.accept_vis (vis);
+}
+
+bool
+Fragment::is_single_fragment () const
+{
+  return nodes.size () == 1;
+}
+
+bool
+Fragment::is_single_fragment_of_kind (SingleASTNode::NodeType expected) const
+{
+  return is_single_fragment () && nodes[0].get_kind () == expected;
+}
+
+void
+Fragment::assert_single_fragment (SingleASTNode::NodeType expected) const
+{
+  static const std::map<SingleASTNode::NodeType, const char *> str_map = {
+    {SingleASTNode::NodeType::IMPL, "impl"},
+    {SingleASTNode::NodeType::ITEM, "item"},
+    {SingleASTNode::NodeType::TYPE, "type"},
+    {SingleASTNode::NodeType::EXPRESSION, "expr"},
+    {SingleASTNode::NodeType::STMT, "stmt"},
+    {SingleASTNode::NodeType::EXTERN, "extern"},
+    {SingleASTNode::NodeType::TRAIT, "trait"},
+    {SingleASTNode::NodeType::TRAIT_IMPL, "trait impl"},
+  };
+
+  auto actual = nodes[0].get_kind ();
+  auto fail = false;
+
+  if (!is_single_fragment ())
+    {
+      rust_error_at (Location (), "fragment is not single");
+      fail = true;
+    }
+
+  if (actual != expected)
+    {
+      rust_error_at (
+	Location (),
+	"invalid fragment operation: expected %qs node, got %qs node",
+	str_map.find (expected)->second,
+	str_map.find (nodes[0].get_kind ())->second);
+      fail = true;
+    }
+
+  rust_assert (!fail);
+}
+
+} // namespace AST
+} // namespace Rust