Parse exclusive range pattern

Exclusive range pattern were not handled by the parser as this an
experimental feature.

gcc/rust/ChangeLog:

	* ast/rust-pattern.cc (tokenid_to_rangekind): Add a new function to
	get a range kind from the current token type.
	(RangePattern::as_string): Change the string representation for range
	pattern in order to handle excluded ranges.
	* ast/rust-pattern.h (enum class): Add new enum class to differentiate
	range kinds.
	(tokenid_to_rangekind): New prototype for a function that converts a
	token id to it's corresponding range kind.
	(class RangePattern): Change the class to accept a range kind instead
	of an ellipsis boolean.
	* hir/rust-ast-lower-pattern.cc (ASTLoweringPattern::visit): Abort
	when an excluded pattern has been found as we do not handle their
	lowering yet.
	* parse/rust-parse-impl.h (Parser::parse_literal_or_range_pattern):
	Parse excluded range patterns.
	(Parser::parse_pattern_no_alt): Likewise.
	(Parser::parse_ident_leading_pattern): Likewise.

Signed-off-by: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/gcc/rust/hir/rust-ast-lower-pattern.cc b/gcc/rust/hir/rust-ast-lower-pattern.cc
index 138e4b7..784c29a 100644
--- a/gcc/rust/hir/rust-ast-lower-pattern.cc
+++ b/gcc/rust/hir/rust-ast-lower-pattern.cc
@@ -18,6 +18,7 @@
 
 #include "rust-ast-lower-pattern.h"
 #include "rust-ast-lower-expr.h"
+#include "rust-system.h"
 
 namespace Rust {
 namespace HIR {
@@ -253,6 +254,8 @@ ASTLoweringPattern::visit (AST::LiteralPattern &pattern)
 void
 ASTLoweringPattern::visit (AST::RangePattern &pattern)
 {
+  if (pattern.get_range_kind () == AST::RangeKind::EXCLUDED)
+    rust_unreachable (); // Not supported yet
   auto upper_bound = lower_range_pattern_bound (pattern.get_upper_bound ());
   auto lower_bound = lower_range_pattern_bound (pattern.get_lower_bound ());