From be44018b3846e774f1d2f16fe06570f7647e3075 Mon Sep 17 00:00:00 2001
From: Vincent Moens <vmoens@meta.com>
Date: Thu, 9 Jan 2025 13:22:47 +0000
Subject: [PATCH 1/2] [BugFix] Consistent behavior for pad_sequence with one
 and many non-tensors

ghstack-source-id: c74edd95ed9846c14ffe26cb176d93c6e5e0dfbf
Pull Request resolved: https://github.com/pytorch/tensordict/pull/1172
---
 tensordict/functional.py | 2 +-
 test/test_tensordict.py  | 7 +++++++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/tensordict/functional.py b/tensordict/functional.py
index 2699f36bb..226e55da1 100644
--- a/tensordict/functional.py
+++ b/tensordict/functional.py
@@ -216,7 +216,7 @@ def pad_sequence(
         try:
             item0 = list_of_dicts[0][key]
             if is_non_tensor(item0):
-                out.set(key, torch.stack([d[key] for d in list_of_dicts]))
+                out.set(key, TensorDict.lazy_stack([d[key] for d in list_of_dicts]))
                 continue
             tensor_shape = item0.shape
             pos_pad_dim = (
diff --git a/test/test_tensordict.py b/test/test_tensordict.py
index a77cb11e7..60ba211a9 100644
--- a/test/test_tensordict.py
+++ b/test/test_tensordict.py
@@ -1920,6 +1920,13 @@ def test_pad_sequence_nontensor(self):
         assert (d["a"] == torch.tensor([[1, 1], [2, 0]])).all()
         assert d["b"] == ["asd", "efg"]
 
+    def test_pad_sequence_single_nontensor(self):
+        d1 = TensorDict({"a": torch.tensor([1, 1]), "b": "asd"})
+        d = pad_sequence([d1])
+        assert (d["a"] == torch.tensor([[1, 1]])).all()
+        assert d["b"] == ["asd"]
+        assert isinstance(d.get("b"), NonTensorStack)
+
     def test_pad_sequence_tensorclass_nontensor(self):
         @tensorclass
         class Sample:

From a63e7f35a4c6118f104378bd75b9dcc888d90e61 Mon Sep 17 00:00:00 2001
From: Vincent Moens <vmoens@meta.com>
Date: Thu, 9 Jan 2025 18:17:05 +0000
Subject: [PATCH 2/2] [CI] Update the download-artifacts version (#1177)

---
 .github/workflows/wheels-windows.yml | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/.github/workflows/wheels-windows.yml b/.github/workflows/wheels-windows.yml
index 63357de8e..75044091f 100644
--- a/.github/workflows/wheels-windows.yml
+++ b/.github/workflows/wheels-windows.yml
@@ -36,12 +36,12 @@ jobs:
             python3 -mpip install wheel
             TENSORDICT_BUILD_VERSION=0.6.2 python3 setup.py bdist_wheel
       - name: Upload wheel for the test-wheel job
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: tensordict-win-${{ matrix.python_version[0] }}.whl
           path: dist/tensordict-*.whl
       - name: Upload wheel for download
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: tensordict-batch.whl
           path: dist/*.whl
@@ -72,7 +72,7 @@ jobs:
         run: |
           python3 -mpip install numpy pytest pytest-cov codecov unittest-xml-reporting pillow>=4.1.1 scipy av networkx expecttest pyyaml
       - name: Download built wheels
-        uses: actions/download-artifact@v3
+        uses: actions/download-artifact@v4
         with:
           name: tensordict-win-${{ matrix.python_version }}.whl
           path: wheels