Why format differently, using vscode extension: Same version, Different os platform

[CYx-HHH]

my local os+entension version is(mac os):
~/.vscode/extensions/charliermarsh.ruff-2025.28.0-darwin-arm64/bundled/libs/bin/ruff

my remote os+exrension version is(ubuntu):
~/.vscode-server/extensions/charliermarsh.ruff-2025.28.0/bundled/libs/bin/ruff

same code:

fieldA = models.CharField(verbose_name='fieldAAA', max_length=1024, null=True, default=None, blank=True, db_index=False)
fieldB = models.IntegerField(verbose_name='fieldBBB', max_length=32, null=True, default=0, db_index=False)

def my_func(arg_one, arg_two, arg_three):
    pass
...

local format as:

fieldB = models.IntegerField(
    verbose_name='fieldB',
    default=0
)

but on remote left unchanged.

Why ruff act differently with same version & config?

local and remote using same vscode settings:
formatOnSave,defaultFormatter,...etc

same ruff settings:
line-length=240

[MichaReiser]

Hi @CYx-HHH

I'll need a few more information to help you:

• Do you have any ruff.toml or pyproject.toml (locally or remote) and, if so, what are their contents
• How did you configure the line-length?
• Can you follow our troubleshooting guide and share the logs from the output panel with us? Ideally from local and remote but remote is probably enough because I suspect that its the remote server that's not finding the settings (or using different settings)

[CYx-HHH]

The config toml:

[tool.ruff]
# Allow lines to be as long as 240
line-length = 240

[tool.ruff.format]
quote-style = "single"

And I ask Gemini, it tells me to run vscode-extension-ruff format on terminal, like this:

export REMOTE_RUFF_BIN=~/.vscode/extensions/charliermarsh.ruff-2025.28.0-darwin-arm64/bundled/libs/bin/ruff
$REMOTE_RUFF_BIN
$REMOTE_RUFF_BIN format ./models.py --line-length=240

I run this on both sides with same file content, and format result is same as before.
It also helps me to check other possible formatter extension conflicts setting on vscode, the settings json is:

 "markdown-preview-enhanced.breakOnSingleNewLine": false,
  "markdown-preview-enhanced.automaticallyShowPreviewOfMarkdownBeingEdited": true,
  "markdown-preview-enhanced.codeBlockTheme": "atom-light.css",
  "markdown-preview-enhanced.imageFolderPath": "./pics",
  "markdown-preview-enhanced.markdownFileExtensions": [
    ".md",
    ".markdown",
    ".mdown",
    ".mkdn",
    ".mkd",
    ".rmd",
    ".qmd",
    ".mdx"
  ],
  "workbench.editor.enablePreviewFromCodeNavigation": true,
  "[python]": {
    "files.autoSave": "afterDelay",
    "editor.defaultFormatter": "charliermarsh.ruff",
    "editor.formatOnSave": true,
    "diffEditor.ignoreTrimWhitespace": true
  },
  "git.openRepositoryInParentFolders": "never",
  "editor.minimap.enabled": false,
  "[markdown]": {
    "editor.defaultFormatter": "yzhang.markdown-all-in-one"
  },
  "markdown-preview-enhanced.previewTheme": "none.css",
  "markdown-preview-enhanced.revealjsTheme": "white.css",
  "terminal.integrated.defaultProfile.osx": "zsh",
  "terminal.integrated.defaultProfile.linux": "bash",
  "terminal.integrated.env.osx": {},
  "terminal.integrated.profiles.windows": {
    "PowerShell": {
      "source": "PowerShell",
      "icon": "terminal-powershell"
    },
    "Command Prompt": {
      "path": [
        "${env:windir}\\Sysnative\\cmd.exe",
        "${env:windir}\\System32\\cmd.exe"
      ],
      "args": [],
      "icon": "terminal-cmd"
    },
    "Git Bash": {
      "source": "Git Bash"
    }
  },
  "prettier.requireConfig": true,
  "eslint.validate": [
    "javascript",
    "javascriptreact",
    "typescript",
    "typescriptreact",
    "vue"
  ],
  "typescript.validate.enable": false,
  "javascript.validate.enable": false,
  "[javascript]": {
    "editor.defaultFormatter": "esbenp.prettier-vscode"
  },
  "[vue]": {
    "editor.defaultFormatter": "esbenp.prettier-vscode"
  },
  "vue.server.includeLanguages": [
    "vue"
  ],
  "[typescript]": {
    "editor.defaultFormatter": "esbenp.prettier-vscode"
  },
  "typescript.tsdk": "node_modules/typescript/lib",
  "vue-helper.framework": "element-plus",

same config on both local & remote.

[CYx-HHH]

Hi! I just got the answer. it all depends on the ',' comma on the last definition field.
The code on remote is different with the local:

if with ',', it formats as multi line; if not, it remains unchanged one line.

fieldA = models.CharField(verbose_name='fieldAAA', max_length=1024, null=True, default=None, blank=True, db_index=False)

and

fieldA = models.CharField(verbose_name='fieldAAA', max_length=1024, null=True, default=None, blank=True, db_index=False,)

[MichaReiser]

Oh nice find. Yes, a trailing comma forces the line to split. You can change this behavior using skip-magic-trailing-comma