What causes "Native file picker is not supported on this platform" in gitbutlerapp/gitbutler?

Run on a supported platform (macOS, Linux, or Windows) where a native picker is compiled in.

Native file picker is not supported on this platform

Error message

Native file picker is not supported on this platform

What it means

`native_pick_directory` only implements native folder choosers for macOS (osascript), Linux (zenity/kdialog), and Windows (PowerShell WinForms), gated by `#[cfg(...)]` attributes. On any other target the `#[cfg(not(any(...)))]` branch unconditionally bails with this message — the feature simply does not exist on that platform.

Solutions

Run on a supported platform (macOS, Linux, or Windows) where a native picker is compiled in.
Provide the directory path directly via the API/CLI instead of invoking the native picker.
If you must support the platform, extend `native_pick_directory` with a new cfg branch implementing a picker (or a plain path prompt fallback).

Defensive patterns

Strategy: type-guard

Validate before calling

// Only call the picker on platforms with a compiled-in implementation
if cfg!(any(target_os = "macos", target_os = "linux", target_os = "windows")) {
    pick_directory().await?;
} else {
    let dir = prompt_for_path_manually();
}

Type guard

fn native_picker_available() -> bool {
    cfg!(any(target_os = "macos", target_os = "linux", target_os = "windows"))
}

Try / catch

match pick_directory().await {
    Err(e) if e.to_string().contains("not supported on this platform") => {
        let dir = prompt_for_path_manually(); // non-native fallback
    }
    other => other?,
}

Prevention

Gate picker calls behind a platform check (cfg! or a capability flag).
Always ship a non-native path-entry fallback for unsupported targets.
Document platform support for the picker endpoint in client code.

When it happens

Trigger: Calling the native directory-picker endpoint in a but-server build for an OS other than macOS, Linux, or Windows (e.g. FreeBSD, or a wasm/non-std target), or running a cross-compiled binary whose cfg gates excluded the picker implementations (crates/but-server/src/lib.rs:224).

Common situations: Running but-server on an unsupported/unusual Unix flavor; embedding the server in a non-desktop target; testing a cross-compiled build where no native picker was compiled in.

Understand the failure class

Background: "unsupported platform" / "not supported on this platform" errors: what they mean and how to fix them — this error's family across 47 libraries.

Related errors

AI-assisted analysis of gitbutlerapp/gitbutler@58e5313667 (2026-09-18). Data as JSON: /api/errors/f3573b8abe0d625f. Report an issue: GitHub.

Appendix: source

Thrown at crates/but-server/src/lib.rs:225

                "PowerShell directory picker failed (exit {:?}): {}",
                output.status.code(),
                if stderr.is_empty() {
                    "unknown error"
                } else {
                    &stderr
                }
            );
        }
        let path = String::from_utf8_lossy(&output.stdout).trim().to_string();
        if path.is_empty() {
            return Ok(None);
        }
        Ok(Some(path))
    }

    #[cfg(not(any(target_os = "macos", target_os = "linux", target_os = "windows")))]
    {
        anyhow::bail!("Native file picker is not supported on this platform")
    }
}

fn cmd_result_to_json(res: anyhow::Result<serde_json::Value>) -> Json<serde_json::Value> {
    match res {
        Ok(value) => Json(json!(Response::Success(value))),
        Err(e) => {
            let e = json::Error::from(e);
            Json(json!(Response::Error(json!(e))))
        }
    }
}

/// Check if an origin byte string is from localhost.
///
/// Matches `http(s)://localhost`, `http(s)://127.0.0.1`, and
/// `http(s)://[::1]`, each optionally followed by `:<port>`.
pub(crate) fn is_localhost_origin(origin: &[u8]) -> bool {

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