Method count_commits

atomic-cli/src/commands/git/import.rs:403–456

Count the commits a real import would create, for dry-run mode. In incremental mode this applies the exact same skip rules as the real import — already-imported SHAs and self-pushed commits whose view state is already present — via [`incremental_import_skips`], so the forecast matches what the import would actually bring in.

(
        &self,
        git_repo: &GitRepository,
        head_oid: git2::Oid,
        imported_shas: &HashSet<String>,
        known_states: &HashSet<atomic_core::types::Merkle>,
        target_view

    /// is already present — via [`incremental_import_skips`], so the forecast
    /// matches what the import would actually bring in.
    fn count_commits(
        &self,
        git_repo: &GitRepository,
        head_oid: git2::Oid,
        imported_shas: &HashSet<String>,
        known_states: &HashSet<atomic_core::types::Merkle>,
        target_view: &str,
        mainline_only: bool,
    ) -> CliResult<usize> {
        let mut revwalk = git_repo.revwalk().map_err(|e| CliError::GitError {
            message: format!("Failed to create revwalk: {}", e),
        })?;

        revwalk.push(head_oid).map_err(|e| CliError::GitError {
            message: format!("Failed to push HEAD to revwalk: {}", e),
        })?;

        if mainline_only {
            revwalk
                .simplify_first_parent()
                .map_err(|e| CliError::GitError {
                    message: format!("Failed to simplify revwalk to first-parent history: {}", e),
                })?;
        }

        revwalk
            .set_sorting(Sort::TOPOLOGICAL | Sort::REVERSE)
            .map_err(|e| CliError::GitError {
                message: format!("Failed to set sorting: {}", e),
            })?;

        let mut count = 0;
        for oid_result in revwalk {
            let oid = oid_result.map_err(|e| CliError::GitError {
                message: format!("Revwalk error: {}", e),
            })?;

            if self.incremental {
                let sha = oid.to_string();
                let commit = git_repo.find_commit(oid).map_err(|e| CliError::GitError {
                    message: format!("Failed to load commit {}: {}", sha, e),
                })?;
                let message = commit.message().unwrap_or("");
                if incremental_import_skips(&sha, message, imported_shas, target_view, known_states)
                {
                    continue;
                }
            }

            count += 1;
        }

        Ok(count)
    }

    /// Classify the commits an incremental import would bring in and print a
    /// per-shape recommendation (SPEC §4.4). Purely advisory — writes nothing.