parse.y: warn CR

* parse.y (parser_nextc): warn carriage return in middle of line.
  [ruby-core:56240] [Feature #8699]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@42691 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

3 files changed, 24 insertions, 3 deletions

diff --git a/ChangeLog b/ChangeLog
index b1c05dedbb..13a4787221 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Mon Aug 26 16:24:58 2013  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* parse.y (parser_nextc): warn carriage return in middle of line.
+	  [ruby-core:56240] [Feature #8699]
+
 Mon Aug 26 15:27:39 2013  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* lib/timeout.rb (Timeout#timeout): should not be caught by rescue
diff --git a/parse.y b/parse.y
index 76fc9e7104..4af44c0d77 100644
--- a/parse.y
+++ b/parse.y
@@ -270,6 +270,8 @@ struct parser_params {
 
     int parser_yydebug;
 
+    int last_cr_line;
+
 #ifndef RIPPER
     /* Ruby core only */
     NODE *parser_eval_tree_begin;
@@ -5329,6 +5331,7 @@ yycompile0(VALUE arg)
 	    ruby_coverage = coverage(ruby_sourcefile_string, ruby_sourceline);
 	}
     }
+    parser->last_cr_line = ruby_sourceline - 1;
 
     parser_prepare(parser);
     deferred_nodes = 0;
@@ -5611,9 +5614,15 @@ parser_nextc(struct parser_params *parser)
 	}
     }
     c = (unsigned char)*lex_p++;
-    if (c == '\r' && peek('\n')) {
-	lex_p++;
-	c = '\n';
+    if (c == '\r') {
+	if (peek('\n')) {
+	    lex_p++;
+	    c = '\n';
+	}
+	else if (ruby_sourceline > parser->last_cr_line) {
+	    parser->last_cr_line = ruby_sourceline;
+	    rb_compile_warn(ruby_sourcefile, ruby_sourceline, "encountered \\r in mddile of line, treat as a mere space");
+	}
     }
 
     return c;
diff --git a/test/ruby/test_syntax.rb b/test/ruby/test_syntax.rb
index f5ff8a7810..04fcd20a56 100644
--- a/test/ruby/test_syntax.rb
+++ b/test/ruby/test_syntax.rb
@@ -385,6 +385,13 @@ eom
     assert_syntax_error("__END__\r<<<<<\n", /unexpected <</)
   end
 
+  def test_warning_for_cr
+    feature8699 = '[ruby-core:56240] [Feature #8699]'
+    assert_warning(/encountered \\r/, feature8699) do
+      eval("\r""__id__\r")
+    end
+  end
+
   private
 
   def not_label(x) @result = x; @not_label ||= nil end