add defensive handling of vscode api proposal usage

[jankuca]

Summary by CodeRabbit

• Bug Fixes

  • Notebook creation now gracefully handles optional runtime features, avoiding errors when certain integration points are unavailable and improving stability during notebook setup.

• Tests

  • Added unit tests covering controller creation across scenarios: feature present, feature absent, and feature-attachment failures to ensure silent, safe degradation.

[coderabbitai]

📝 Walkthrough

Walkthrough

A guard is added around attaching the Jupyter variableProvider to the notebook controller: the code checks at runtime whether controller.variableProvider exists before assigning and performs the assignment inside a try/catch that logs a warning on failure; if absent the assignment is skipped. Comments document the API's proposed status and the opt-in flag requirement. Unit tests were added covering API-available, API-unavailable, and assignment-throws scenarios. An exported type IConnectionDisplayData was added to src/notebooks/controllers/types.

Sequence Diagram(s)

mermaid
sequenceDiagram
autonumber
participant Creator as ControllerFactory
participant VSCode as NotebookController (runtime)
participant Logger as Logger

Creator->>VSCode: create controller
Note right of VSCode #DDEBF7: Runtime presence check for variableProvider
VSCode-->>VSCode: if ('variableProvider' in controller)
alt variableProvider exists
VSCode->>VSCode: try assign variableProvider
VSCode-->>Logger: on error -> warn("assignment failed")
Note right of VSCode #E8F8E0: assignment inside try/catch
else not present
Note right of VSCode #F7F2F2: skip assignment (graceful degradation)
end
Creator->>VSCode: return controller

mermaid
sequenceDiagram
autonumber
participant Creator as ControllerFactory
participant VSCode as NotebookController (old)
participant Logger as Logger

Creator->>VSCode: create controller
Note right of VSCode #FFF7E6: Previous unconditional assignment
VSCode->>VSCode: try assign variableProvider (unconditionally)
VSCode-->>Logger: on error -> warn("assignment failed")
Creator->>VSCode: return controller

Pre-merge checks

✅ Passed checks (2 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	Title accurately describes the main change: adding defensive checks around VS Code API proposal usage in the variable provider attachment logic.

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📜 Recent review details

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📥 Commits

Reviewing files that changed from the base of the PR and between d7b31e8 and c3e9a64.

📒 Files selected for processing (1)

• src/notebooks/controllers/vscodeNotebookController.unit.test.ts (2 hunks)

🧰 Additional context used

📓 Path-based instructions (1)

**/*.{test,spec}.ts

📄 CodeRabbit inference engine (.github/instructions/typescript.instructions.md)

In unit tests, when a mock is returned from a promise, ensure the mocked instance has an undefined then property to avoid hanging tests

Files:

• src/notebooks/controllers/vscodeNotebookController.unit.test.ts

🧬 Code graph analysis (1)

src/notebooks/controllers/vscodeNotebookController.unit.test.ts (3)

src/notebooks/controllers/types.ts (3)

• IConnectionDisplayDataProvider (135-135)
• IConnectionDisplayDataProvider (136-138)
• IConnectionDisplayData (126-133)

src/kernels/variables/types.ts (2)

• IJupyterVariablesProvider (149-149)
• IJupyterVariablesProvider (150-150)

src/notebooks/controllers/vscodeNotebookController.ts (1)

• VSCodeNotebookController (96-820)

🔇 Additional comments (3)

src/notebooks/controllers/vscodeNotebookController.unit.test.ts (3)

40-40: LGTM - Imports are correct.

The new imports support the variable provider tests.

Also applies to: 45-45

---

549-609: LGTM - Test suite setup is comprehensive.

All dependencies properly mocked and disposed.

---

611-758: LGTM - Test cases cover all scenarios.

The three tests validate:

• Variable provider attached when API available
• Graceful degradation when API missing
• Error handling when assignment throws

Each test uses an appropriate mocking strategy for its scenario.

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[codecov]

Codecov Report

❌ Patch coverage is 92.45283% with 4 lines in your changes missing coverage. Please review.
✅ Project coverage is 73%. Comparing base (b47df83) to head (c3e9a64).
⚠️ Report is 1 commits behind head on main.
✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
.../controllers/vscodeNotebookController.unit.test.ts	91%	4 Missing ⚠️

Additional details and impacted files

@@          Coverage Diff          @@
##            main    #174   +/-   ##
=====================================
  Coverage     73%     73%           
=====================================
  Files        574     574           
  Lines      46813   46863   +50     
  Branches    5519    5520    +1     
=====================================
+ Hits       34358   34410   +52     
+ Misses     10637   10635    -2     
  Partials    1818    1818           

Files with missing lines	Coverage Δ
.../notebooks/controllers/vscodeNotebookController.ts	36% <100%> (+1%)	⬆️
.../controllers/vscodeNotebookController.unit.test.ts	95% <91%> (-1%)	⬇️

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