Function output_file_to_buffer

atomic-core/src/output/repo/file.rs:756–818

Output a file to a buffer instead of the working copy. This is useful for testing, previewing, or cases where you want the content in memory rather than written to disk. # Arguments `txn` - Transaction providing graph access `changes` - Change store for retrieving span content `position` - Position in the graph `options` - Output options # Returns A tuple of (content bytes, conflicts). # Err

(
    txn: &T,
    changes: &C,
    position: Position<NodeId>,
    options: FileOutputOptions,
)

/// println!("File content:\n{}", text);
/// ```
pub fn output_file_to_buffer<T, C>(
    txn: &T,
    changes: &C,
    position: Position<NodeId>,
    options: FileOutputOptions,
) -> Result<(Vec<u8>, Vec<FileConflict>), OutputError>
where
    T: GraphTxnT,
    C: ChangeStore,
{
    // Retrieve the alive graph
    let retrieve_opts = options.to_retrieve_options();
    let retrieve_result = retrieve_graph(txn, position, retrieve_opts)
        .map_err(|e| OutputError::Pristine(Box::new(e)))?;

    // Handle empty graph
    if retrieve_result.graph.is_empty() {
        return Ok((Vec::new(), Vec::new()));
    }

    // Compute SCC ordering
    let mut graph = retrieve_result.graph;
    let order = compute_order(&mut graph);

    // Create buffer writer
    let buffer = Vec::new();
    let mut writer = Writer::new(buffer);

    // Hash function to convert NodeId to Hash using the transaction.
    // This is required for the ChangeStore to load the correct change file
    // and retrieve the content bytes for each span.
    let hash_fn = |node_id: NodeId| -> Option<Hash> {
        // Handle ROOT node - it has no hash
        if node_id.is_root() {
            return None;
        }
        // Use transaction's get_external to convert NodeId to Hash
        txn.get_external(node_id).ok().flatten()
    };

    // Attempt semantic merge for any conflicting SCCs
    let resolved = resolve_conflicts_semantically(txn, changes, &graph, &order);

    // Output the graph content (with semantic merge resolution)
    output_graph_content_resolved(changes, hash_fn, &graph, &order, &mut writer, &resolved)?;

    // Extract buffer
    let content = writer.into_inner();

    // Extract conflicts from cyclic SCCs (only those NOT resolved by semantic merge)
    let mut conflicts = Vec::new();
    let mut conflict_id: u32 = 0;
    for scc in &order.sccs {
        if scc.len() > 1 && resolved.get_merged(scc[0]).is_none() {
            conflict_id += 1;
            conflicts.push(
                FileConflict::new(String::new(), FileConflictType::Cyclic).with_id(conflict_id),
            );