Unexpected Execution of KeyboardInterrupt when First Run A Code that Can Block Task #25720
Description
Type: Bug
Description
When running Python code that requires blocking input (e.g., input()) for the first time in a new shell, VS Code triggers an unexpected KeyboardInterrupt.
This issue only occurs inside a Python virtual environment (venv).
Running the same code a second time (and any subsequent times) works normally.
This behavior does not occur when using the system Python interpreter.
I am using the default "python" debug configuration provided by VS Code.
Steps to Reproduce
-
Open VS Code.
-
Create or activate a Python venv.
-
Run a simple blocking script, for example:
input("Enter something: ")
-
Observe that VS Code immediately raises a KeyboardInterrupt on the first run.
-
Run the same script again in the same shell.
-
The script works normally without interruption.
Expected Behavior
The script should wait for user input normally on the first run, just like it does on subsequent runs.
Actual Behavior
On the first execution in a new shell:
The program is interrupted automatically.
A KeyboardInterrupt is raised without any user action.
On second and later executions:
The script behaves normally and waits for input.
Additional Notes
The issue only appears when using a virtual environment.
The issue does not occur with the system Python interpreter.
I am using the default "python" launch configuration generated by VS Code.
ScreenShot_2026-01-09_04-46-44.mp4
Environment：
VS Code version: 1.108.0
Python extension version: 2025.21.2026010601
Operating System: Windows 11 25H2 26200.7462
Python version: python 3.14.2
Virtual environment type: venv
Shell used: PowerShell
Extension version: 2025.21.2026010601
VS Code version: Code 1.108.0 (94e8ae2b28cb5cc932b86e1070569c4463565c37, 2026-01-08T13:53:10.781Z)
OS version: Windows_NT x64 10.0.26200
Modes:
- Python version (& distribution if applicable, e.g. Anaconda): 3.14.2
- Type of virtual environment used (e.g. conda, venv, virtualenv, etc.): System
- Value of the
python.languageServersetting: Default
User Settings
languageServer: "Pylance"
Installed Extensions
| Extension Name | Extension Id | Version |
|---|---|---|
| autodocstring | njp | 0.6.1 |
| copilot-chat | Git | 0.35.3 |
| debugpy | ms- | 2025.19.2025121701 |
| even-better-toml | tam | 0.21.2 |
| js-debug | ms- | 1.105.0 |
| js-debug-companion | ms- | 1.1.3 |
| jupyter | ms- | 2025.10.2026010601 |
| jupyter-keymap | ms- | 1.1.2 |
| jupyter-renderers | ms- | 1.3.2025062701 |
| python | ms- | 2025.21.2026010601 |
| remote-containers | ms- | 0.438.0 |
| remote-explorer | ms- | 0.5.0 |
| remote-server | ms- | 1.5.3 |
| remote-ssh | ms- | 0.122.0 |
| remote-ssh-edit | ms- | 0.87.0 |
| remote-wsl | ms- | 0.104.3 |
| ruff | cha | 2026.34.0 |
| vscode-docker | ms- | 2.0.0 |
| vscode-js-profile-table | ms- | 1.0.10 |
| vscode-jupyter-cell-tags | ms- | 0.1.9 |
| vscode-jupyter-slideshow | ms- | 0.1.6 |
| vscode-language-pack-zh-hans | MS- | 1.108.2026010709 |
| vscode-pylance | ms- | 2025.10.100 |
| vscode-python-envs | ms- | 1.15.13521015 |
| vscode-remote-extensionpack | ms- | 0.26.0 |
System Info
| Item | Value |
|---|---|
| CPUs | 13th Gen Intel(R) Core(TM) i7-13650HX (20 x 2803) |
| GPU Status | 2d_canvas: enabled direct_rendering_display_compositor: disabled_off_ok gpu_compositing: enabled multiple_raster_threads: enabled_on opengl: enabled_on rasterization: enabled raw_draw: disabled_off_ok skia_graphite: disabled_off trees_in_viz: disabled_off video_decode: enabled video_encode: enabled webgl: enabled webgl2: enabled webgpu: enabled webnn: disabled_off |
| Load (avg) | undefined |
| Memory (System) | 31.63GB (18.07GB free) |
| Process Argv | --crash-reporter-id 57e8a3cf-b24b-44a7-a2da-975ff851ba3d |
| Screen Reader | no |
| VM | 0% |
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