Move WindowsSymlinkOverride logic to Runtime

dvc/__init__.py

@@ -1,30 +1,5 @@
-import os
-import ctypes
-
-
-class WindowsSymlinkOverride(object):
-    FUNC = None
-
-    def __init__(self):
-        func = ctypes.windll.kernel32.CreateSymbolicLinkW
-        func.argtypes = (ctypes.c_wchar_p, ctypes.c_wchar_p, ctypes.c_uint32)
-        func.restype = ctypes.c_ubyte
-
-        WindowsSymlinkOverride.FUNC = func
-
-    @staticmethod
-    def symlink(source, link_name):
-        '''symlink(source, link_name) - DVC override for Windows
-           Creates a symbolic link pointing to source named link_name'''
-
-        flags = 0
-        if source is not None and os.path.isdir(source):
-            flags = 1
-        if WindowsSymlinkOverride.FUNC(link_name, source, flags) == 0:
-            raise ctypes.WinError()
+from dvc.runtime import Runtime
 
 
 def setup():
-    if os.name == 'nt':
-        os.symlink = WindowsSymlinkOverride().symlink
-    pass
+    Runtime.symlink_setup()

dvc/runtime.py

@@ -1,5 +1,6 @@
 import os
 import sys
+import ctypes
 
 from dvc.config import Config, ConfigI
 from dvc.exceptions import DvcException
@@ -10,6 +11,31 @@ from dvc.settings import Settings
 
 class Runtime(object):
     CONFIG = 'dvc.conf'
+    SYMLINC_OVERRIDE = None
+
+    @staticmethod
+    def symlink_setup():
+        if os.name != 'nt':
+            return
+
+        func = ctypes.windll.kernel32.CreateSymbolicLinkW
+        func.argtypes = (ctypes.c_wchar_p, ctypes.c_wchar_p, ctypes.c_uint32)
+        func.restype = ctypes.c_ubyte
+
+        Runtime.SYMLINC_OVERRIDE = func
+
+        os.symlink = Runtime.symlink
+
+    @staticmethod
+    def symlink(source, link_name):
+        '''symlink(source, link_name) - DVC override for Windows
+           Creates a symbolic link pointing to source named link_name'''
+
+        flags = 0
+        if source is not None and os.path.isdir(source):
+            flags = 1
+        if Runtime.SYMLINC_OVERRIDE(link_name, source, flags) == 0:
+            raise ctypes.WinError()
 
     @staticmethod
     def conf_file_path(git_dir):
@@ -18,6 +44,7 @@ class Runtime(object):
     @staticmethod
     def run(cmd_class, parse_config=True):
         try:
+            Runtime.symlink_setup()
             runtime_git = GitWrapper()
 
             if parse_config: