Pylint doesn't take anymore the default rcfile if the rcfile specified on the...

Pylint doesn't take anymore the default rcfile if the rcfile specified on the command line doesn't exist (#1768)

ChangeLog

@@ -173,6 +173,10 @@ What's New in Pylint 1.8?
       of ``line-too-long`` message for long commented lines.
       Close #1741
+    * If the rcfile specified on the command line doesn't exist, then an
+      IOError exception is raised.
+      Close #1747
+
 What's New in Pylint 1.7.1?
 =========================

doc/whatsnew/1.8.rst

@@ -364,3 +364,6 @@ Other Changes
 * Fix ``line-too-long`` message deactivated by wrong disable directive.
   The directive ``disable=fixme`` doesn't deactivate anymore the emission 
   of ``line-too-long`` message for long commented lines.
+
+* If the rcfile specified on the command line doesn't exist, then an
+  IOError exception is raised.

pylint/config.py

@@ -626,6 +626,8 @@ class OptionsManagerMixIn(object):
             config_file = self.config_file
         if config_file is not None:
             config_file = os.path.expanduser(config_file)
+            if not os.path.exists(config_file):
+                raise IOError("The config file {:s} doesn't exist!".format(config_file))
         use_config_file = config_file and os.path.exists(config_file)
         if use_config_file:

pylint/test/test_self.py

@@ -169,6 +169,12 @@ class TestRunTC(object):
         output = out.getvalue()
         assert "profile" not in output
+    def test_inexisting_rcfile(self):
+        out = six.StringIO()
+        with pytest.raises(IOError) as excinfo:
+            self._run_pylint(["--rcfile=/tmp/norcfile.txt"], out=out)
+        assert "The config file /tmp/norcfile.txt doesn't exist!" == str(excinfo.value)
+
     def test_help_message_option(self):
         self._runtest(['--help-msg', 'W0101'], code=0)