Function migrate

src/config.rs:166–215

Fold a [`RawConfig`] into the canonical [`PersistedConfig`], returning the upgraded persisted state and a flag indicating whether the on-disk shape needed changes (in which case the caller should re-persist). Bails if the file was written by a newer schema version than this CLI knows about, to avoid silently downgrading it (which would drop any fields the newer schema added).

(raw: RawConfig)

/// CLI knows about, to avoid silently downgrading it (which would
/// drop any fields the newer schema added).
fn migrate(raw: RawConfig) -> Result<(PersistedConfig, bool)> {
    // Fast path: already at the current schema version. Legacy fields
    // cannot exist in a v1 file we wrote, so anything stray is a hand
    // edit and we deliberately ignore it.
    if raw.version == Some(CURRENT_CONFIG_VERSION) {
        let mut profiles = raw.profiles;
        profiles.entry(DEFAULT_PROFILE_NAME.to_owned()).or_default();
        return Ok((
            PersistedConfig {
                version: CURRENT_CONFIG_VERSION,
                profiles,
            },
            false,
        ));
    }

    let raw_version = raw.version.unwrap_or(0);
    if raw_version > CURRENT_CONFIG_VERSION {
        bail!(
            "Config file was written by a newer version of CodSpeed (schema v{raw_version}, this CLI supports v{CURRENT_CONFIG_VERSION}). Upgrade the CLI to read it."
        );
    }
    let mut dirty = raw_version != CURRENT_CONFIG_VERSION;

    let mut profiles = raw.profiles;

    // v0 → v1: move legacy top-level auth.token into profiles.default
    // (only if the profile slot is empty, so we don't clobber a value
    // the user explicitly set per-profile).
    if let Some(legacy_auth) = raw.auth
        && let Some(token) = legacy_auth.token
    {
        dirty = true;
        let default_profile = profiles.entry(DEFAULT_PROFILE_NAME.to_owned()).or_default();
        if default_profile.auth.token.is_none() {
            default_profile.auth.token = Some(token);
        }
    }

    // Ensure the default profile exists so consumers can rely on it.
    profiles.entry(DEFAULT_PROFILE_NAME.to_owned()).or_default();

    Ok((
        PersistedConfig {
            version: CURRENT_CONFIG_VERSION,
            profiles,
        },
        dirty,
    ))
}

/// Write the canonical [`PersistedConfig`] to disk.
fn write_persisted(persisted: &PersistedConfig, config_name: Option<&str>) -> Result<()> {