Python formatting very slow in Dev Container

[adiun]

Issue Type: Bug

Behaviour

Expected vs. Actual

Expected:

• Fast to save a file with 'formatOnSave' set to true inside a dev container

Actual:

• takes ~6 seconds to sort imports and then format code
• Note: that it seems to be fast outside of a dev container
• Note: This seems to have regressed with build 2022.01786462952. The build before it, 2021.12.1559732655 does not have this issue. The latest build, 2022.0.1814523869, still has this issue.

Steps to reproduce:

1. Create a Dockerfile that:
   • Installs an editable poetry package
   • Here is the list of dev dependencies in pyproject.toml:

[tool.poetry.dev-dependencies]
bandit = "^1.7.1"
black = "^21.11b0"
flake8 = "^4.0.1"
isort = "^5.10.1"
markdown = "3.3.4"
pytest = "^5.2"
pytest-mock = "^3.6.1"
mkdocs = "^1.2.3"
mkdocstrings = "^0.16.2"
ipykernel = "^6.6.0"
pytest-recording = "^0.12.0"

2. Create a devcontainer.json like this:

  "settings": {
    // Resolve import errors in Jupyter / ipython
    "[json]": {
      "editor.defaultFormatter": "esbenp.prettier-vscode"
    },
    "[jsonc]": {
      "editor.defaultFormatter": "esbenp.prettier-vscode"
    },
    "[python]": {
      "editor.tabSize": 4
    },
    "editor.codeActionsOnSave": {
      "source.organizeImports": true
    },
    "editor.formatOnSave": true,
    "editor.tabSize": 2,
    "python.analysis.extraPaths": ["sdk"],
    "python.defaultInterpreterPath": "/opt/conda/bin/python",
    "python.formatting.provider": "black",
    "python.linting.banditEnabled": true,
    "python.linting.flake8Enabled": true,
    "python.testing.pytestEnabled": true,
    "python.testing.unittestEnabled": false,
    "terminal.integrated.inheritEnv": false
  },

  // Add the IDs of extensions you want installed when the container is created.
  "extensions": [
    "amodio.toggle-excluded-files",
    "bierner.markdown-emoji",
    "esbenp.prettier-vscode",

    "ms-python.python",
    "ms-python.vscode-pylance",
    "ms-toolsai.jupyter",
    "tamasfe.even-better-toml",
    "timonwong.shellcheck",
    "yzhang.markdown-all-in-one"
  ]

Diagnostic data

• Python version (& distribution if applicable, e.g. Anaconda): 3.9.7
• Type of virtual environment used (e.g. conda, venv, virtualenv, etc.): Conda
• Value of the python.languageServer setting: Default

User Settings

defaultLS: {"defaultLSType":"Pylance"}

downloadLanguageServer: true

envFile: "<placeholder>"

venvPath: "<placeholder>"

venvFolders: "<placeholder>"

condaPath: "<placeholder>"

pipenvPath: "<placeholder>"

poetryPath: "<placeholder>"

languageServer: "Pylance"

linting
• enabled: true
• cwd: "<placeholder>"
• Flake8Args: "<placeholder>"
• flake8Enabled: true
• flake8Path: "<placeholder>"
• lintOnSave: true
• banditArgs: "<placeholder>"
• banditEnabled: true
• banditPath: "<placeholder>"
• mypyArgs: "<placeholder>"
• mypyEnabled: false
• mypyPath: "<placeholder>"
• pycodestyleArgs: "<placeholder>"
• pycodestyleEnabled: false
• pycodestylePath: "<placeholder>"
• prospectorArgs: "<placeholder>"
• prospectorEnabled: false
• prospectorPath: "<placeholder>"
• pydocstyleArgs: "<placeholder>"
• pydocstyleEnabled: false
• pydocstylePath: "<placeholder>"
• pylamaArgs: "<placeholder>"
• pylamaEnabled: false
• pylamaPath: "<placeholder>"
• pylintArgs: "<placeholder>"
• pylintPath: "<placeholder>"

sortImports
• args: "<placeholder>"
• path: "<placeholder>"

formatting
• autopep8Args: "<placeholder>"
• autopep8Path: "<placeholder>"
• provider: "black"
• blackArgs: "<placeholder>"
• blackPath: "<placeholder>"
• yapfArgs: "<placeholder>"
• yapfPath: "<placeholder>"

testing
• cwd: "<placeholder>"
• debugPort: 3000
• nosetestArgs: "<placeholder>"
• nosetestsEnabled: undefined
• nosetestPath: "<placeholder>"
• promptToConfigure: true
• pytestArgs: "<placeholder>"
• pytestEnabled: true
• pytestPath: "<placeholder>"
• unittestArgs: "<placeholder>"
• unittestEnabled: false
• autoTestDiscoverOnSaveEnabled: true

terminal
• activateEnvironment: true
• executeInFileDir: "<placeholder>"
• launchArgs: "<placeholder>"

experiments
• enabled: true
• optInto: []
• optOutFrom: []

insidersChannel: "off"

tensorBoard
• logDirectory: "<placeholder>"

Extension version: 2022.0.1814523869
VS Code version: Code 1.64.1 (d6ee99e4c045a6716e5c653d7da8e9ae6f5a8b03, 2022-02-07T17:26:08.977Z)
OS version: Darwin x64 20.6.0
Restricted Mode: No
Remote OS version: Linux x64 5.10.76-linuxkit

System Info

Item	Value
CPUs	Intel(R) Core(TM) i9-9980HK CPU @ 2.40GHz (16 x 2400)
GPU Status	2d_canvas: enabled gpu_compositing: enabled metal: disabled_off multiple_raster_threads: enabled_on oop_rasterization: enabled opengl: enabled_on rasterization: enabled skia_renderer: disabled_off_ok video_decode: enabled webgl: enabled webgl2: enabled
Load (avg)	6, 4, 3
Memory (System)	32.00GB (0.20GB free)
Process Argv	--crash-reporter-id 4758608f-d190-4905-8b7b-9580cf264aef
Screen Reader	no
VM	0%

Item	Value
Remote	Dev Container: Sandbox
OS	Linux x64 5.10.76-linuxkit
CPUs	Intel(R) Core(TM) i9-9980HK CPU @ 2.40GHz (8 x 2400)
Memory (System)	1.94GB (0.52GB free)
VM	0%

A/B Experiments

vsliv368:30146709
vsreu685:30147344
python383cf:30185419
vspor879:30202332
vspor708:30202333
vspor363:30204092
pythonvspyl392:30425749
pythontb:30283811
pythonvspyt551:30345470
pythonptprofiler:30281270
vshan820:30294714
vstes263:30335439
pythondataviewer:30285071
vscod805cf:30301675
pythonvspyt200:30340761
binariesv615:30325510
bridge0708:30335490
bridge0723:30353136
vsaa593cf:30376535
vsc1dst:30433059
pythonvs932:30410667
wslgetstarted:30433507
vsrem710:30416614
vsbas813:30436447
vscscmwlcmt:30433761

[karthiknadig]

@adiun does it help if you set the formatter path and isort path?

[adiun]

@karthiknadig that fixes it, Thanks! I added this to devcontainer.json (depends on which black and which sort)

    "python.formatting.blackPath": "/opt/conda/bin/black",
    "python.sortImports.path": "/opt/conda/bin/isort",

[karthiknadig]

This started happening after transition to conda run, this should be addressed generically when we do #18469

[alkatar21]

This started happening after transition to conda run, this should be addressed generically when we do #18469

Will this be solved in the next release? This is currently very annoying.

[karthiknadig]

@alkatar21 This is not an issue with the extension. The perf issues are due conda run itself being slow. That said if you want to tryout the prototype, we have you can find it here psf/black#2883, hhatto/autopep8#624