el-retired/_archive/rust-bootstrap/engrams/el-registry/src/resolve.rs

//! Dependency resolution — convert a manifest's dependency map into a flat
//! ordered list of resolved packages.

use std::collections::HashMap;

use el_manifest::Dependency;

use crate::client::{PackageMetadata, RegistryClient};
use crate::error::RegistryResult;

/// Resolve all registry dependencies in `deps` to concrete versions.
///
/// Path dependencies are skipped (they are local and do not need network
/// resolution).
pub async fn resolve_deps(
    client: &RegistryClient,
    deps: &HashMap<String, Dependency>,
) -> RegistryResult<Vec<PackageMetadata>> {
    let mut resolved = Vec::new();

    for (name, dep) in deps {
        match dep {
            Dependency::VersionReq(req) => {
                let meta = client.fetch_metadata(name, req).await?;
                resolved.push(meta);
            }
            Dependency::Registry { version, .. } => {
                let meta = client.fetch_metadata(name, version).await?;
                resolved.push(meta);
            }
            Dependency::Path(_) => {
                // Path deps resolve to the local directory — nothing to fetch.
            }
        }
    }

    // Sort by name for deterministic ordering.
    resolved.sort_by(|a, b| a.name.cmp(&b.name));
    Ok(resolved)
}