1 files changed, 100 insertions, 0 deletions
diff --git a/lib/python2.7/test/symlink_support.py b/lib/python2.7/test/symlink_support.py
new file mode 100644
index 0000000..301d0f9
--- /dev/null
+++ b/lib/python2.7/test/symlink_support.py
@@ -0,0 +1,100 @@
+import os
+import unittest
+import platform
+
+from test.test_support import TESTFN
+
+def can_symlink():
+    # cache the result in can_symlink.prev_val
+    prev_val = getattr(can_symlink, 'prev_val', None)
+    if prev_val is not None:
+        return prev_val
+    symlink_path = TESTFN + "can_symlink"
+    try:
+        symlink(TESTFN, symlink_path)
+        can = True
+    except (OSError, NotImplementedError, AttributeError):
+        can = False
+    else:
+        os.remove(symlink_path)
+    can_symlink.prev_val = can
+    return can
+
+def skip_unless_symlink(test):
+    """Skip decorator for tests that require functional symlink"""
+    ok = can_symlink()
+    msg = "Requires functional symlink implementation"
+    return test if ok else unittest.skip(msg)(test)
+
+def _symlink_win32(target, link, target_is_directory=False):
+    """
+    Ctypes symlink implementation since Python doesn't support
+    symlinks in windows yet. Borrowed from jaraco.windows project.
+    """
+    import ctypes.wintypes
+    CreateSymbolicLink = ctypes.windll.kernel32.CreateSymbolicLinkW
+    CreateSymbolicLink.argtypes = (
+        ctypes.wintypes.LPWSTR,
+        ctypes.wintypes.LPWSTR,
+        ctypes.wintypes.DWORD,
+        )
+    CreateSymbolicLink.restype = ctypes.wintypes.BOOLEAN
+
+    def format_system_message(errno):
+        """
+        Call FormatMessage with a system error number to retrieve
+        the descriptive error message.
+        """
+        # first some flags used by FormatMessageW
+        ALLOCATE_BUFFER = 0x100
+        ARGUMENT_ARRAY = 0x2000
+        FROM_HMODULE = 0x800
+        FROM_STRING = 0x400
+        FROM_SYSTEM = 0x1000
+        IGNORE_INSERTS = 0x200
+
+        # Let FormatMessageW allocate the buffer (we'll free it below)
+        # Also, let it know we want a system error message.
+        flags = ALLOCATE_BUFFER | FROM_SYSTEM
+        source = None
+        message_id = errno
+        language_id = 0
+        result_buffer = ctypes.wintypes.LPWSTR()
+        buffer_size = 0
+        arguments = None
+        bytes = ctypes.windll.kernel32.FormatMessageW(
+            flags,
+            source,
+            message_id,
+            language_id,
+            ctypes.byref(result_buffer),
+            buffer_size,
+            arguments,
+            )
+        # note the following will cause an infinite loop if GetLastError
+        #  repeatedly returns an error that cannot be formatted, although
+        #  this should not happen.
+        handle_nonzero_success(bytes)
+        message = result_buffer.value
+        ctypes.windll.kernel32.LocalFree(result_buffer)
+        return message
+
+    def handle_nonzero_success(result):
+        if result == 0:
+            value = ctypes.windll.kernel32.GetLastError()
+            strerror = format_system_message(value)
+            raise WindowsError(value, strerror)
+
+    target_is_directory = target_is_directory or os.path.isdir(target)
+    handle_nonzero_success(CreateSymbolicLink(link, target, target_is_directory))
+
+symlink = os.symlink if hasattr(os, 'symlink') else (
+    _symlink_win32 if platform.system() == 'Windows' else None
+)
+
+def remove_symlink(name):
+    # On Windows, to remove a directory symlink, one must use rmdir
+    try:
+        os.rmdir(name)
+    except OSError:
+        os.remove(name)