From 0e8e45c74068b72301f9045f0efc38ba8b51e0a4 Mon Sep 17 00:00:00 2001
From: Masaki Hara <ackie.h.gmai@gmail.com>
Date: Mon, 8 May 2017 22:29:24 +0900
Subject: [PATCH] Allow bare CR in ////-style comment.

---
 src/libsyntax/parse/lexer/mod.rs               |  2 +-
 .../lex-bare-cr-string-literal-doc-comment.rs  |  6 ++++++
 .../run-pass/lex-bare-cr-nondoc-comment.rs     | 18 ++++++++++++++++++
 3 files changed, 25 insertions(+), 1 deletion(-)
 create mode 100644 src/test/run-pass/lex-bare-cr-nondoc-comment.rs

diff --git a/src/libsyntax/parse/lexer/mod.rs b/src/libsyntax/parse/lexer/mod.rs
index 7d2a1b3c4a4d2..ded1f0b599a61 100644
--- a/src/libsyntax/parse/lexer/mod.rs
+++ b/src/libsyntax/parse/lexer/mod.rs
@@ -504,7 +504,7 @@ impl<'a> StringReader<'a> {
                     self.bump();
 
                     // line comments starting with "///" or "//!" are doc-comments
-                    let doc_comment = self.ch_is('/') || self.ch_is('!');
+                    let doc_comment = (self.ch_is('/') && !self.nextch_is('/')) || self.ch_is('!');
                     let start_bpos = self.pos - BytePos(2);
 
                     while !self.is_eof() {
diff --git a/src/test/parse-fail/lex-bare-cr-string-literal-doc-comment.rs b/src/test/parse-fail/lex-bare-cr-string-literal-doc-comment.rs
index f894305754319..ac085d475114e 100644
--- a/src/test/parse-fail/lex-bare-cr-string-literal-doc-comment.rs
+++ b/src/test/parse-fail/lex-bare-cr-string-literal-doc-comment.rs
@@ -21,6 +21,12 @@ pub fn bar() {}
 //~^^ ERROR: bare CR not allowed in block doc-comment
 
 fn main() {
+    //! doc comment with bare CR: '
'
+    //~^ ERROR: bare CR not allowed in doc-comment
+
+    /*! block doc comment with bare CR: '
' */
+    //~^ ERROR: bare CR not allowed in block doc-comment
+
     // the following string literal has a bare CR in it
     let _s = "foo
bar"; //~ ERROR: bare CR not allowed in string
 
diff --git a/src/test/run-pass/lex-bare-cr-nondoc-comment.rs b/src/test/run-pass/lex-bare-cr-nondoc-comment.rs
new file mode 100644
index 0000000000000..ba949ca88814d
--- /dev/null
+++ b/src/test/run-pass/lex-bare-cr-nondoc-comment.rs
@@ -0,0 +1,18 @@
+// Copyright 2014 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.
+
+// ignore-tidy-cr
+
+// nondoc comment with bare CR: '
'
+//// nondoc comment with bare CR: '
'
+/* block nondoc comment with bare CR: '
' */
+
+fn main() {
+}