Fix Windows CI failure: disable symlinks during dependency installation

[Copilot]

Windows CI jobs fail when installing jupyterlab-widgets==3.0.16 due to restricted symlink creation. The project configures uv with link-mode = "symlink" in pyproject.toml, which triggers this Windows limitation.

Changes

• Added UV_NO_SYMLINKS: "true" environment variable at the job level in .github/workflows/ci.yml

This configuration:

• Sets the environment variable at the job level (not step level) to ensure it applies consistently to all uv invocations
• Uses the string value "true" instead of numeric 1 for proper uv interpretation
• Overrides the symlink behavior for all CI platforms while preserving local development configuration

Original prompt

---

This section details on the original issue you should resolve

<issue_title>The failing job encountered an error during installation of jupyterlab-widget</issue_title>
<issue_description>The failing job encountered an error during installation of jupyterlab-widgets==3.0.16 due to a failed symlink creation on Windows:

error: Failed to install: jupyterlab_widgets-3.0.16-py3-none-any.whl Caused by: failed to symlink ...\jupyterlab-manager\static\packages_base_lib_index_js-webpack_sharing_consume_default_jquer

This is a known issue with some Python wheel packages on Windows when using tools that attempt to create symlinks, since the Windows environment often restricts symlinks by default.

Solution:

Add the --no-symlink option to the command that installs dependencies in your workflow (if supported).
For uv, try setting the environment variable UV_NO_SYMLINKS to 1 before installation. Update your Setup dependencies step in .github/workflows/ci.yml:
YAML

• name: Setup dependencies
  run: |
  uv python pin ${{ matrix.python-version }}
  uv export --no-managed-python --no-group doc --resolution ${{ matrix.resolution }} > ci-requirements.txt
  uv pip install --system -r ci-requirements.txt
  env:
  UV_NO_SYMLINKS: 1
  Alternatively, upgrade uv and jupyterlab-widgets to their latest versions if possible, as recent releases may have fixed this issue.

These changes should resolve the symlink error and allow the workflow to complete successfully on Windows runners.</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes The failing job encountered an error during installation of jupyterlab-widget #47

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[harell]

@copilot The job is failing during dependency installation on Windows because the installer is trying to create a symlink while installing jupyterlab-widgets==3.0.16, and that symlink operation fails on the GitHub-hosted Windows runner:

• Error in logs: failed to symlink file ... jupyterlab_widgets-3.0.16 ...
• This is a common Windows limitation (symlink permissions / long paths / file system semantics), and it can happen even when you intend to disable symlinks.

Fix: ensure uv truly does not use symlinks on Windows

In your workflow, you already set UV_NO_SYMLINKS: 1, but the failure indicates uv still attempted a symlink. The most reliable fix is to set the env var to the value uv expects and scope it explicitly for Windows (and/or set it globally for the job).

Update .github/workflows/ci.yml (ref: 7b792d9888767009219eb2b323c2632682a9bde7) around the “Setup dependencies” step.

Option A (recommended): set a job-level env for Windows

Add this under jobs.tests.env: so it applies consistently:

jobs:
  tests:
    runs-on: ${{ matrix.os }}
    env:
      PYTHONIOENCODING: utf-8
      UV_NO_SYMLINKS: "true"

Then remove the step-level UV_NO_SYMLINKS block (optional, but keeps things clean).

Option B: set it only for Windows in the dependencies step

Replace the env: block in “Setup dependencies” with:

      - name: Setup dependencies
        run: |
          uv python pin ${{ matrix.python-version }}
          uv export --no-managed-python --no-group doc --resolution ${{ matrix.resolution }} > ci-requirements.txt 
          uv pip install --system -r ci-requirements.txt
        env:
          UV_NO_SYMLINKS: ${{ matrix.os == 'windows-latest' && 'true' || '' }}

(If you prefer clarity, you can instead split into two dependency steps: one with the env var for Windows and one without for other OSes.)

Why this solves it

The failure is specifically: Caused by: failed to symlink file ... while installing a wheel containing JupyterLab extension assets. Forcing uv into “copy mode” (no symlinks) avoids the Windows symlink operation entirely, which is the point of failure.

If you apply the job-level env (Option A), it also ensures the setting can’t be missed by any other uv invocation in the job.

[Copilot]

@copilot The job is failing during dependency installation on Windows because the installer is trying to create a symlink while installing jupyterlab-widgets==3.0.16, and that symlink operat...

Fixed in ee1d25b. Moved UV_NO_SYMLINKS to job-level environment variables with string value "true" and removed the step-level env block for consistency.

[t-t-sonarqube]

Quality Gate passed

Issues

• 0 New Issues
• 0 Fixed Issues
• 0 Accepted Issues

Measures

• 0 Security Hotspots
• 0.00% Coverage (92.50% Estimated after merge)
• 0.00% Duplicated Code (0.00% Estimated after merge)

Project ID: tonkintaylor_ruru_9df383a8-3ce9-4983-bccc-45fb680571e3

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