default settings should provide dart.lineLength inherited from Zed settings

[notpeter]

The default settings passed to the language server should include line length from Zed settings.

dart.lineLength (int?): Sets a default value for the formatter to wrap code at if no value is specified in formatter.page_width in analysis_options.yaml. If unspecified by both, code will be wrapped at 80 characters.

https://github.com/dart-lang/sdk/blob/main/pkg/analysis_server/tool/lsp_spec/README.md

[nicpaimnt]

This is annoying indeed and prevents me to work in Zed.

I'd take any hardcoded option in the meanwhile... I tried editorconfig etc. no use.

[notpeter]

Can you try adding this to your settings (worked for me):

  "lsp": {
    "dart": {
      "settings": {
        "lineLength": 140
      }
    }
  }

[notpeter]

I'm not sure whether it's possible to this with current Extensions API.
Native Languages can access AllLanguageSettings:

https://github.com/zed-industries/zed/blob/892a0e4c9a26e1fae0a86b7e1bd36608fa681994/crates/languages/src/yaml.rs#L103-L116

But the Extensions API LanguageSettings only includes tab_size

#[derive(Debug, Serialize, Deserialize)]
pub struct LanguageSettings {
    /// How many columns a tab should occupy.
    pub tab_size: NonZeroU32,
}