fix(parser): Correctly handle DOS new lines in 'line' rules

Do not consider the trailing `\r` of a line a part of it.

yamllint/parser.py

@@ -77,7 +77,10 @@ def line_generator(buffer):
     cur = 0
     next = buffer.find('\n')
     while next != -1:
-        yield Line(line_no, buffer, start=cur, end=next)
+        if next > 0 and buffer[next - 1] == '\r':
+            yield Line(line_no, buffer, start=cur, end=next - 1)
+        else:
+            yield Line(line_no, buffer, start=cur, end=next)
         cur = next + 1
         next = buffer.find('\n', cur)
         line_no += 1

yamllint/rules/empty_lines.py

@@ -66,27 +66,37 @@ DEFAULT = {'max': 2,
 def check(conf, line):
     if line.start == line.end and line.end < len(line.buffer):
         # Only alert on the last blank line of a series
-        if (line.end < len(line.buffer) - 1 and
-                line.buffer[line.end + 1] == '\n'):
+        if (line.end + 2 <= len(line.buffer) and
+                line.buffer[line.end:line.end + 2] == '\n\n'):
+            return
+        elif (line.end + 4 <= len(line.buffer) and
+              line.buffer[line.end:line.end + 4] == '\r\n\r\n'):
             return
 
         blank_lines = 0
 
-        while (line.start > blank_lines and
-               line.buffer[line.start - blank_lines - 1] == '\n'):
+        start = line.start
+        while start >= 2 and line.buffer[start - 2:start] == '\r\n':
             blank_lines += 1
+            start -= 2
+        while start >= 1 and line.buffer[start - 1] == '\n':
+            blank_lines += 1
+            start -= 1
 
         max = conf['max']
 
         # Special case: start of document
-        if line.start - blank_lines == 0:
+        if start == 0:
             blank_lines += 1  # first line doesn't have a preceding \n
             max = conf['max-start']
 
         # Special case: end of document
         # NOTE: The last line of a file is always supposed to end with a new
         # line. See POSIX definition of a line at:
-        if line.end == len(line.buffer) - 1 and line.buffer[line.end] == '\n':
+        if ((line.end == len(line.buffer) - 1 and
+             line.buffer[line.end] == '\n') or
+            (line.end == len(line.buffer) - 2 and
+             line.buffer[line.end:line.end + 2] == '\r\n')):
             # Allow the exception of the one-byte file containing '\n'
             if line.end == 0:
                 return

yamllint/rules/new_lines.py

@@ -36,10 +36,11 @@ DEFAULT = {'type': 'unix'}
 def check(conf, line):
     if line.start == 0 and len(line.buffer) > line.end:
         if conf['type'] == 'dos':
-            if line.buffer[line.end - 1:line.end + 1] != '\r\n':
+            if (line.end + 2 > len(line.buffer) or
+                    line.buffer[line.end:line.end + 2] != '\r\n'):
                 yield LintProblem(1, line.end - line.start + 1,
                                   'wrong new line character: expected \\r\\n')
         else:
-            if line.end > 0 and line.buffer[line.end - 1] == '\r':
-                yield LintProblem(1, line.end - line.start,
+            if line.buffer[line.end] == '\r':
+                yield LintProblem(1, line.end - line.start + 1,
                                   'wrong new line character: expected \\n')