From e01150731b245306027c98241ba2a1b136611882 Mon Sep 17 00:00:00 2001
From: Kyle Cutler <kycutler@microsoft.com>
Date: Fri, 7 Jan 2022 15:07:04 -0800
Subject: [PATCH 1/3] Normalize debugger temp file paths on Windows

---
 ipykernel/compiler.py | 10 ++++++++--
 ipykernel/debugger.py |  2 +-
 setup.py              |  1 +
 3 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/ipykernel/compiler.py b/ipykernel/compiler.py
index 0b1384021..472116beb 100644
--- a/ipykernel/compiler.py
+++ b/ipykernel/compiler.py
@@ -39,8 +39,14 @@ def murmur2_x86(data, seed):
 
 def get_tmp_directory():
     tmp_dir = tempfile.gettempdir()
+    if os.name == 'nt':
+        try:
+            import win32file
+            tmp_dir = win32file.GetLongPathName(tmp_dir)
+        except:
+            pass
     pid = os.getpid()
-    return tmp_dir + '/ipykernel_' + str(pid)
+    return tmp_dir + os.sep + 'ipykernel_' + str(pid)
 
 
 def get_tmp_hash_seed():
@@ -52,7 +58,7 @@ def get_file_name(code):
     cell_name = os.environ.get("IPYKERNEL_CELL_NAME")
     if cell_name is None:
         name = murmur2_x86(code, get_tmp_hash_seed())
-        cell_name = get_tmp_directory() + '/' + str(name) + '.py'
+        cell_name = get_tmp_directory() + os.sep + str(name) + '.py'
     return cell_name
 
 
diff --git a/ipykernel/debugger.py b/ipykernel/debugger.py
index 62c6a5407..d1ce0ff8f 100644
--- a/ipykernel/debugger.py
+++ b/ipykernel/debugger.py
@@ -507,7 +507,7 @@ async def debugInfo(self, message):
                 'isStarted': self.is_started,
                 'hashMethod': 'Murmur2',
                 'hashSeed': get_tmp_hash_seed(),
-                'tmpFilePrefix': get_tmp_directory() + '/',
+                'tmpFilePrefix': get_tmp_directory() + os.sep,
                 'tmpFileSuffix': '.py',
                 'breakpoints': breakpoint_list,
                 'stoppedThreads': self.stopped_threads,
diff --git a/setup.py b/setup.py
index 95dffbc66..dfff0d5dc 100644
--- a/setup.py
+++ b/setup.py
@@ -69,6 +69,7 @@ def run(self):
         'matplotlib-inline>=0.1.0,<0.2.0',
         'appnope;platform_system=="Darwin"',
         'nest_asyncio',
+        'pywin32;platform_system=="Windows"'
     ],
     extras_require={
         "test": [

From 4d873e0ac59cc160859afab2e5de256a62aff9d3 Mon Sep 17 00:00:00 2001
From: Kyle Cutler <kycutler@microsoft.com>
Date: Mon, 10 Jan 2022 09:08:39 -0800
Subject: [PATCH 2/3] Use ctypes instead of pywin32

---
 ipykernel/compiler.py | 33 ++++++++++++++++++++++++++-------
 setup.py              |  1 -
 2 files changed, 26 insertions(+), 8 deletions(-)

diff --git a/ipykernel/compiler.py b/ipykernel/compiler.py
index 472116beb..a38e45378 100644
--- a/ipykernel/compiler.py
+++ b/ipykernel/compiler.py
@@ -1,6 +1,7 @@
 from IPython.core.compilerop import CachingCompiler
 import tempfile
 import os
+import sys
 
 
 def murmur2_x86(data, seed):
@@ -36,15 +37,33 @@ def murmur2_x86(data, seed):
 
     return h
 
+convert_to_long_pathname = lambda filename:filename
+
+if sys.platform == 'win32':
+    try:
+        import ctypes
+        from ctypes.wintypes import MAX_PATH, LPCWSTR, LPWSTR, DWORD
+
+        _GetLongPathName = ctypes.windll.kernel32.GetLongPathNameW
+        _GetLongPathName.argtypes = [LPCWSTR, LPWSTR, DWORD]
+        _GetLongPathName.restype = DWORD
+
+        def _convert_to_long_pathname(filename):
+            buf = ctypes.create_unicode_buffer(MAX_PATH)
+            rv = _GetLongPathName(filename, buf, MAX_PATH)
+            if rv != 0 and rv <= MAX_PATH:
+                filename = buf.value
+            return filename
+
+        # test that it works
+        _convert_to_long_pathname(__file__)
+    except:
+        pass
+    else:
+        convert_to_long_pathname = _convert_to_long_pathname
 
 def get_tmp_directory():
-    tmp_dir = tempfile.gettempdir()
-    if os.name == 'nt':
-        try:
-            import win32file
-            tmp_dir = win32file.GetLongPathName(tmp_dir)
-        except:
-            pass
+    tmp_dir = convert_to_long_pathname(tempfile.gettempdir())
     pid = os.getpid()
     return tmp_dir + os.sep + 'ipykernel_' + str(pid)
 
diff --git a/setup.py b/setup.py
index dfff0d5dc..95dffbc66 100644
--- a/setup.py
+++ b/setup.py
@@ -69,7 +69,6 @@ def run(self):
         'matplotlib-inline>=0.1.0,<0.2.0',
         'appnope;platform_system=="Darwin"',
         'nest_asyncio',
-        'pywin32;platform_system=="Windows"'
     ],
     extras_require={
         "test": [

From 6ffb3d33f4a24d06b09edb85d53e06aa6ae6d73a Mon Sep 17 00:00:00 2001
From: Kyle Cutler <kycutler@microsoft.com>
Date: Mon, 10 Jan 2022 09:58:25 -0800
Subject: [PATCH 3/3] Add test, clarify reason for inline check

---
 ipykernel/compiler.py            | 2 +-
 ipykernel/tests/test_debugger.py | 6 ++++++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/ipykernel/compiler.py b/ipykernel/compiler.py
index a38e45378..95770e7be 100644
--- a/ipykernel/compiler.py
+++ b/ipykernel/compiler.py
@@ -55,7 +55,7 @@ def _convert_to_long_pathname(filename):
                 filename = buf.value
             return filename
 
-        # test that it works
+        # test that it works so if there are any issues we fail just once here
         _convert_to_long_pathname(__file__)
     except:
         pass
diff --git a/ipykernel/tests/test_debugger.py b/ipykernel/tests/test_debugger.py
index ab9f13a2c..65f5711e1 100644
--- a/ipykernel/tests/test_debugger.py
+++ b/ipykernel/tests/test_debugger.py
@@ -271,3 +271,9 @@ def test_rich_inspect_at_breakpoint(kernel_with_debug):
     )
 
     assert reply["body"]["data"] == {"text/plain": locals_[0]["value"]}
+
+
+def test_convert_to_long_pathname():
+    if sys.platform == 'win32':
+        from ipykernel.compiler import _convert_to_long_pathname
+        _convert_to_long_pathname(__file__)
\ No newline at end of file