Revert "Revert "depr: deprecate strict in from_native / to_native …

…in favour of `pass_through` (#1312)

.github/workflows/downstream_tests.yml

@@ -1,8 +1,9 @@
 name: Test Downstream Libraries
 
 on: 
-  workflow_call:
-  workflow_dispatch:
+  pull_request:
+  push:
+    branches: [main]
 
 jobs:
   altair:
@@ -230,59 +231,59 @@ jobs:
             cd tubular
             pytest tests --config-file=pyproject.toml
   
-  vegafusion:
-     env:
-       UV_SYSTEM_PYTHON: true
+  # vegafusion:
+  #    env:
+  #      UV_SYSTEM_PYTHON: true
 
-     strategy:
-       matrix:
-         python-version: ["3.11"]
-         os: [ubuntu-latest]
+  #    strategy:
+  #      matrix:
+  #        python-version: ["3.11"]
+  #        os: [ubuntu-latest]
 
-     runs-on: ${{ matrix.os }}
-     steps:
-        - uses: actions/checkout@v4
-        - uses: actions/setup-python@v5
-          with:
-            python-version: ${{ matrix.python-version }}
-        - name: Install uv
-          uses: astral-sh/setup-uv@v3
-          with:
-            enable-cache: "true"
-            cache-suffix: ${{ matrix.python-version }}
-            cache-dependency-glob: "**requirements*.txt"
-        - name: clone-vegafusion
-          run: |
-              git clone --single-branch -b v2 https://github.com/vega/vegafusion.git
-              cd vegafusion
-              git log
-        - name: Cache rust dependencies
-          uses: Swatinem/rust-cache@v2
-          with:
-            workspaces: vegafusion
-        - name: Build wheels
-          uses: PyO3/maturin-action@v1
-          with:
-            command: build
-            manylinux: 2014
-            rust-toolchain: stable
-            args: --release -m vegafusion/vegafusion-python/Cargo.toml --features=protobuf-src --strip
-        - name: Install wheels
-          working-directory: vegafusion/target/wheels/
-          run: |
-            ls -la
-            python -m pip install vegafusion-*manylinux*.whl
+  #    runs-on: ${{ matrix.os }}
+  #    steps:
+  #       - uses: actions/checkout@v4
+  #       - uses: actions/setup-python@v5
+  #         with:
+  #           python-version: ${{ matrix.python-version }}
+  #       - name: Install uv
+  #         uses: astral-sh/setup-uv@v3
+  #         with:
+  #           enable-cache: "true"
+  #           cache-suffix: ${{ matrix.python-version }}
+  #           cache-dependency-glob: "**requirements*.txt"
+  #       - name: clone-vegafusion
+  #         run: |
+  #             git clone --single-branch -b v2 https://github.com/vega/vegafusion.git
+  #             cd vegafusion
+  #             git log
+  #       - name: Cache rust dependencies
+  #         uses: Swatinem/rust-cache@v2
+  #         with:
+  #           workspaces: vegafusion
+  #       - name: Build wheels
+  #         uses: PyO3/maturin-action@v1
+  #         with:
+  #           command: build
+  #           manylinux: 2014
+  #           rust-toolchain: stable
+  #           args: --release -m vegafusion/vegafusion-python/Cargo.toml --features=protobuf-src --strip
+  #       - name: Install wheels
+  #         working-directory: vegafusion/target/wheels/
+  #         run: |
+  #           ls -la
+  #           python -m pip install vegafusion-*manylinux*.whl
 
-            # Optional dependencies
-            python -m pip install pyarrow pandas polars-lts-cpu "duckdb>=1.0" "vl-convert-python>=1.0.1rc1" scikit-image "pandas>=2.2" jupytext voila anywidget ipywidgets chromedriver-binary-auto
+  #           # Optional dependencies
+  #           python -m pip install pyarrow pandas polars-lts-cpu "duckdb>=1.0" "vl-convert-python>=1.0.1rc1" scikit-image "pandas>=2.2" jupytext voila anywidget ipywidgets chromedriver-binary-auto
 
-            # Test dependencies
-            python -m pip install pytest altair vega-datasets scikit-image jupytext voila ipykernel anywidget ipywidgets selenium flaky tenacity chromedriver-binary-auto 
-        - name: Test lazy imports
-          working-directory: vegafusion/vegafusion-python/
-          run: python checks/check_lazy_imports.py
-        - name: Test vegafusion
-          working-directory: vegafusion/vegafusion-python/
-          env:
-            VEGAFUSION_TEST_HEADLESS: 1
-          run: pytest
+  #           # Test dependencies
+  #           python -m pip install pytest altair vega-datasets scikit-image jupytext voila ipykernel anywidget ipywidgets selenium flaky tenacity chromedriver-binary-auto 
+  #       - name: Test lazy imports
+  #         working-directory: vegafusion/vegafusion-python/
+  #         run: python checks/check_lazy_imports.py
+  #       - name: Test vegafusion
+  #         working-directory: vegafusion/vegafusion-python/
+  #         env:
+  #           VEGAFUSION_TEST_HEADLESS: 1
+  #         run: pytest

docs/backcompat.md

@@ -99,8 +99,27 @@ before making any change.
 
 ### After `stable.v1`
 
-- `Datetime` and `Duration` dtypes hash using both `time_unit` and `time_zone`.
-    The effect of this can be seen when doing `dtype in {...}` checks:
+- Since Narwhals 1.13.0, the `strict` parameter in `from_native`, `to_native`, and `narwhalify`
+    has been deprecated in favour of `pass_through`. This is because several users expressed
+    confusion/surprise over what `strict=False` did.
+    ```python
+    # v1 syntax:
+    nw.from_native(df, strict=False)
+
+    # main namespace (and, when we get there, v2) syntax:
+    nw.from_native(df, pass_through=True)
+    ```
+    If you are using Narwhals>=1.13.0, then we recommend using `pass_through`, as that
+    works consistently across namespaces.
+
+    In the future:
+
+    - in the main Narwhals namespace, `strict` will be removed in favour of `pass_through`
+    - in `stable.v1`, we will keep both `strict` and `pass_through`
+
+- Since Narwhals 1.9.0, `Datetime` and `Duration` dtypes hash using both `time_unit` and
+    `time_zone`.
+    The effect of this can be seen when placing these dtypes in sets:
 
     ```python exec="1" source="above" session="backcompat"
     import narwhals.stable.v1 as nw_v1

narwhals/dataframe.py

@@ -2874,7 +2874,7 @@ def to_native(self) -> FrameT:
             └─────┴─────┴─────┘
         """
 
-        return to_native(narwhals_object=self, strict=True)
+        return to_native(narwhals_object=self, pass_through=False)
 
     # inherited
     def pipe(self, function: Callable[[Any], Self], *args: Any, **kwargs: Any) -> Self:

narwhals/functions.py

@@ -361,7 +361,7 @@ def _from_dict_impl(
         else:
             msg = "Calling `from_dict` without `native_namespace` is only supported if all input values are already Narwhals Series"
             raise TypeError(msg)
-        data = {key: to_native(value, strict=False) for key, value in data.items()}
+        data = {key: to_native(value, pass_through=True) for key, value in data.items()}
     implementation = Implementation.from_native_namespace(native_namespace)
 
     if implementation is Implementation.POLARS: