Method get_file_content_via_crdt

atomic-repository/src/repository/content.rs:135–166

Get file content using the CRDT-driven walker (task #24). Walks the `Trunk → Branch` chain in file order and fetches each alive branch's bytes from its recorded `BRANCH_VERTEX` span. This bypasses the byte-graph linear walker entirely. # When to use Use this when you want the *materialized* file content — the state after all applied changes — without filtering by view. This is correct for sin

(
        &self,
        path: P,
    )

    /// for this file (legacy repos that predate CRDT population) or when
    /// any alive branch lacks a `BRANCH_VERTEX` mapping.
    pub fn get_file_content_via_crdt<P: AsRef<Path>>(
        &self,
        path: P,
    ) -> Result<Option<Vec<u8>>, RepositoryError> {
        use atomic_core::output::crdt::{output_file_via_crdt, CrdtOutputError};

        let path = path.as_ref();
        let normalized = normalize_path(path);

        let txn = self
            .pristine
            .read_txn()
            .map_err(|e| RepositoryError::Database(e.to_string()))?;

        match output_file_via_crdt(&txn, &self.change_store, &normalized) {
            Ok(content) if !content.is_empty() => Ok(Some(content)),
            Ok(_) => {
                // Empty result — file not in CRDT layer.  Fall back to the
                // view-scoped byte-graph walker.
                drop(txn);
                self.get_file_content(path)
            }
            Err(CrdtOutputError::OrphanBranch(_)) => {
                // Alive branch without BRANCH_VERTEX — pre-walker data.
                // Fall back to byte-graph walker.
                drop(txn);
                self.get_file_content(path)
            }
            Err(CrdtOutputError::Pristine(e)) => Err(RepositoryError::Database(e.to_string())),
            Err(CrdtOutputError::Store(e)) => Err(RepositoryError::Database(e.to_string())),
        }
    }

    /// Get file content, excluding a specific change.
    ///