Function resolve_introduced_by

atomic-core/src/apply/position.rs:200–218

Resolve the `introduced_by` field of an edge. Returns the NodeId of the change that introduced the original edge. This is used when modifying edges to track provenance. # Arguments `txn` - Transaction for lookups `introduced_by` - Optional hash of the introducing change `current_change` - NodeId of the change being applied # Returns The NodeId of the introducing change.

(
    txn: &T,
    introduced_by: &Option<Hash>,
    current_change: NodeId,
)

///
/// The NodeId of the introducing change.
pub fn resolve_introduced_by<T: GraphTxnT>(
    txn: &T,
    introduced_by: &Option<Hash>,
    current_change: NodeId,
) -> Result<NodeId, LocalApplyError> {
    match introduced_by {
        Some(hash) if hash.is_none() => {
            // Hash::NONE represents the ROOT node
            Ok(NodeId::ROOT)
        }
        Some(hash) => txn
            .get_internal(hash)
            .map_err(|e| LocalApplyError::Internal {
                message: format!("Failed to resolve introduced_by: {}", e),
            })?
            .ok_or(LocalApplyError::DependencyMissing { hash: *hash }),
        None => Ok(current_change),
    }
}

/// Resolve a context position to a span.
///