Fix a small issue about shlex.split not working well with win32 path

AUTHORS

@@ -87,3 +87,4 @@ Russel Winder
 Ben Webb
 Alexei Kozlenok
 Cal Leeming
+Feng Ma

CHANGELOG.rst

@@ -5,7 +5,8 @@
 
 *
 
-*
+* Fix win32 path issue when puttinging custom config file with absolute path 
+  in ``pytest.main("-c your_absolute_path")``.
 
 * Fix maximum recursion depth detection when raised error class is not aware
   of unicode/encoded bytes.

_pytest/config.py

@@ -104,7 +104,7 @@ def _prepareconfig(args=None, plugins=None):
     elif not isinstance(args, (tuple, list)):
         if not isinstance(args, str):
             raise ValueError("not a string or argument list: %r" % (args,))
-        args = shlex.split(args)
+        args = shlex.split(args, posix=sys.platform == "win32")
     config = get_config()
     pluginmanager = config.pluginmanager
     try:

testing/test_config.py

@@ -79,7 +79,7 @@ def test_confcutdir(self, testdir):
         """)
         result = testdir.inline_run("--confcutdir=.")
         assert result.ret == 0
-
+        
 class TestConfigCmdlineParsing:
     def test_parsing_again_fails(self, testdir):
         config = testdir.parseconfig()
@@ -101,6 +101,16 @@ def pytest_addoption(parser):
         config = testdir.parseconfig("-c", "custom.cfg")
         assert config.getini("custom") == "1"
 
+    def test_absolute_win32_path(self, testdir):
+        temp_cfg_file = testdir.makefile(".cfg", custom="""
+            [pytest]
+            addopts = --version
+        """)
+        from os.path import normpath
+        temp_cfg_file = normpath(str(temp_cfg_file))
+        ret = pytest.main("-c " + temp_cfg_file)
+        assert ret == _pytest.main.EXIT_OK
+
 class TestConfigAPI:
     def test_config_trace(self, testdir):
         config = testdir.parseconfig()