ci: allow long file paths before checking out on Windows

Windows defaults to a 260 character path limit, and a checkout that cannot
write a file fails the job before any step of it runs. Tooling that names files
after the tests they belong to reaches that limit without the names being
unreasonable, so a generated project with Windows runners can find its backend
unit tests never running at all.

The config has to be set before the checkout writes the files, so it leads
every job that can run on Windows rather than living in a shared action. Jobs
whose runners are chosen by matrix only get the step when use_windows_in_ci is
set, so a project without Windows runners carries nothing dead.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

Author: ejfine

template/.github/workflows/ci.yaml.jinja

@@ -77,7 +77,13 @@ jobs:
     timeout-minutes: {% endraw %}{{ gha_medium_timeout_minutes }}{% raw %}
     env:
       UV_PYTHON: ${{ matrix.python-version }}
-    steps:
+    steps:{% endraw %}{% if use_windows_in_ci %}
+      - name: Allow long file paths
+        if: runner.os == 'Windows'
+        # Some tooling (e.g. vcrpy, syrupy) generates file names past the 260 character limit Windows
+        # defaults to. This has to happen before the checkout that writes those files.
+        run: git config --global core.longpaths true
+{% endif %}{% raw %}
       - name: Checkout code
         uses: actions/checkout@{% endraw %}{{ gha_checkout }}{% raw %}
 
@@ -170,7 +176,13 @@ jobs:
     env:
       UV_PYTHON: ${{ matrix.python-version }}
 
-    steps:
+    steps:{% endraw %}{% if use_windows_in_exe_ci %}
+      - name: Allow long file paths
+        if: runner.os == 'Windows'
+        # Some tooling (e.g. vcrpy, syrupy) generates file names past the 260 character limit Windows
+        # defaults to. This has to happen before the checkout that writes those files.
+        run: git config --global core.longpaths true
+{% endif %}{% raw %}
       - name: Checkout code
         uses: actions/checkout@{% endraw %}{{ gha_checkout }}{% raw %}
       - name: Install python tooling

template/.github/workflows/release.yaml.jinja

@@ -157,7 +157,13 @@ jobs:
     env:
       UV_PYTHON: ${{ matrix.python-version }}
 
-    steps:
+    steps:{% endraw %}{% if use_windows_in_ci %}
+      - name: Allow long file paths
+        if: runner.os == 'Windows'
+        # Some tooling (e.g. vcrpy, syrupy) generates file names past the 260 character limit Windows
+        # defaults to. This has to happen before the checkout that writes those files.
+        run: git config --global core.longpaths true
+{% endif %}{% raw %}
       - name: Checkout code
         uses: actions/checkout@{% endraw %}{{ gha_checkout }}{% raw %}
       - name: Setup python
@@ -313,7 +319,13 @@ jobs:
     env:
       UV_PYTHON: ${{ matrix.python-version }}
 
-    steps:
+    steps:{% endraw %}{% if use_windows_in_ci %}
+      - name: Allow long file paths
+        if: runner.os == 'Windows'
+        # Some tooling (e.g. vcrpy, syrupy) generates file names past the 260 character limit Windows
+        # defaults to. This has to happen before the checkout that writes those files.
+        run: git config --global core.longpaths true
+{% endif %}{% raw %}
       - name: Checkout code
         uses: actions/checkout@{% endraw %}{{ gha_checkout }}{% raw %}
       - name: Setup python

template/.github/workflows/{% if not deploy_as_executable %}publish.yaml{% endif %}.jinja

@@ -67,7 +67,13 @@ jobs:
     env:
       UV_PYTHON: ${{ matrix.python-version }}
 
-    steps:
+    steps:{% endraw %}{% if use_windows_in_ci %}
+      - name: Allow long file paths
+        if: runner.os == 'Windows'
+        # Some tooling (e.g. vcrpy, syrupy) generates file names past the 260 character limit Windows
+        # defaults to. This has to happen before the checkout that writes those files.
+        run: git config --global core.longpaths true
+{% endif %}{% raw %}
       - name: Checkout code
         uses: actions/checkout@{% endraw %}{{ gha_checkout }}{% raw %}
 
@@ -180,7 +186,13 @@ jobs:
     env:
       UV_PYTHON: ${{ matrix.python-version }}
 
-    steps:
+    steps:{% endraw %}{% if use_windows_in_ci %}
+      - name: Allow long file paths
+        if: runner.os == 'Windows'
+        # Some tooling (e.g. vcrpy, syrupy) generates file names past the 260 character limit Windows
+        # defaults to. This has to happen before the checkout that writes those files.
+        run: git config --global core.longpaths true
+{% endif %}{% raw %}
       - name: Checkout code
         uses: actions/checkout@{% endraw %}{{ gha_checkout }}{% raw %}
       - name: Setup python
@@ -326,7 +338,13 @@ jobs:
     env:
       UV_PYTHON: ${{ matrix.python-version }}
 
-    steps:
+    steps:{% endraw %}{% if use_windows_in_ci %}
+      - name: Allow long file paths
+        if: runner.os == 'Windows'
+        # Some tooling (e.g. vcrpy, syrupy) generates file names past the 260 character limit Windows
+        # defaults to. This has to happen before the checkout that writes those files.
+        run: git config --global core.longpaths true
+{% endif %}{% raw %}
       - name: Checkout code
         uses: actions/checkout@{% endraw %}{{ gha_checkout }}{% raw %}
       - name: Setup python

template/.github/workflows/{% if not deploy_as_executable %}publish_to_staging.yaml{% endif %}.jinja

@@ -41,7 +41,13 @@ jobs:
     env:
       UV_PYTHON: ${{ matrix.python-version }}
 
-    steps:
+    steps:{% endraw %}{% if use_windows_in_ci %}
+      - name: Allow long file paths
+        if: runner.os == 'Windows'
+        # Some tooling (e.g. vcrpy, syrupy) generates file names past the 260 character limit Windows
+        # defaults to. This has to happen before the checkout that writes those files.
+        run: git config --global core.longpaths true
+{% endif %}{% raw %}
       - name: Checkout code
         uses: actions/checkout@{% endraw %}{{ gha_checkout }}{% raw %}