Disallow ._ in float literal.

1 files changed, 13 insertions, 0 deletions

diff --git a/src/test/parse-fail/underscore-suffix-for-float.rs b/src/test/parse-fail/underscore-suffix-for-float.rs
new file mode 100644
index 00000000000..df7d9aa374d
--- /dev/null
+++ b/src/test/parse-fail/underscore-suffix-for-float.rs
@@ -0,0 +1,13 @@
+// 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.
+
+fn main() {
+    let a = 42._; //~ ERROR unexpected token: `_`
+}