Run selection/line in python terminal seems to fail if selected too many characters#25741
Description
Type: Bug
Behaviour
On my MacBook when I select more than around 1100 characters the parsing of the selection is failing and causing then an syntax error when executed in the terminal.
Steps to reproduce:
Select more than 1100 characters with some indentations like functions, classes, loops,...
Then press shift + enter (Python: Run selection/Line in Python Terminal)
Now the data gets parsed wrong and is causing an Error.
screenrecording.mov
Diagnostic data
Output for Python in the Output panel (View→Output, change the drop-down the upper-right of the Output panel to Python)
XXX Extension version: 2026.0.0
VS Code version: Code 1.108.1 (Universal) (585eba7c0c34fd6b30faac7c62a42050bfbc0086, 2026-01-14T14:55:44.241Z)
OS version: Darwin arm64 25.2.0
Modes:
- Python version (& distribution if applicable, e.g. Anaconda): 3.12.12
- Type of virtual environment used (e.g. conda, venv, virtualenv, etc.): Venv
- Value of the
python.languageServersetting: Pylance
User Settings
languageServer: "Pylance" Installed Extensions
| Extension Name | Extension Id | Version |
|---|---|---|
| autodocstring | njp | 0.6.1 |
| copilot-chat | Git | 0.36.1 |
| debugpy | ms- | 2025.18.0 |
| echoapi-for-vscode | Ech | 1.7.13 |
| gitlens | eam | 17.9.0 |
| isort | ms- | 2025.0.0 |
| js-debug | ms- | 1.105.0 |
| js-debug-companion | ms- | 1.1.3 |
| jupyter | ms- | 2025.9.1 |
| jupyter-keymap | ms- | 1.1.2 |
| jupyter-renderers | ms- | 1.3.0 |
| LiveServer | rit | 5.7.9 |
| material-icon-theme | PKi | 5.30.0 |
| python | ms- | 2026.0.0 |
| rainbow-csv | mec | 3.24.1 |
| ruff | cha | 2026.34.0 |
| vscode-js-profile-table | ms- | 1.0.10 |
| vscode-jupyter-cell-tags | ms- | 0.1.9 |
| vscode-jupyter-slideshow | ms- | 0.1.6 |
| vscode-pylance | ms- | 2025.10.4 |
| vscode-python-envs | ms- | 1.16.0 |
| vsliveshare | ms- | 1.0.5959 |
| vsliveshare-pack | ms- | 0.4.0 |
System Info
| Item | Value |
|---|---|
| CPUs | Apple M1 Pro (8 x 2400) |
| 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: enabled_on trees_in_viz: disabled_off video_decode: enabled video_encode: enabled webgl: enabled webgl2: enabled webgpu: enabled webnn: disabled_off |
| Load (avg) | 2, 3, 4 |
| Memory (System) | 16.00GB (0.36GB free) |
| Process Argv | --crash-reporter-id 6c7f7e46-e60f-4b2b-9859-c46c2fc707c1 |
| Screen Reader | no |
| VM | 0% |
A/B Experiments
vsliv368cf:30146710 pythonvspyt551cf:31249601 binariesv615:30325510 nativeloc1:31344060 dwcopilot:31170013 dwoutputs:31242946 copilot_t_ci:31333650 e5gg6876:31282496 pythonrdcb7:31342333 6518g693:31436602 aj953862:31281341 63221493:31336333 cloudbuttont:31379625 42190218_ostrepl:31403339 use-responses-api:31390855 ec5jj548:31422691 cmp-ext-treat:31426748 cp_cls_c_966_ss:31446431 c0683394:31419495 nes-autoexp-off:31446584 a5gib710:31434435 rename_enabled:31436409 7a04d226_do_not_restore_last_panel_session:31438103 anthropic_thinking_t:31432745 cp_cls_c_1081:31443829 copilot-nes-oct-trt:31432596 nes-jump-on-with-edit:31447383 nes-slash-models-on:31441832 nes-set-to-on:31441941 a43f0576c:31442824 ts_provider_disabled:31446105 nes-conv-1-2:31447851