Function export_step_with_log 

pub fn export_step_with_log(
    content: &[u8],
    opts: &StepOptions,
    log: &MutationLog,
) -> Result<(String, LogExportStats)>

Export content with the edits in log applied, as a string.

Byte-identical to the TypeScript StepExporter given the same source and the same log (importMutations into a view wired like the viewer’s), except the GlobalIds of records this export generates. Errs, writing nothing, when the log carries a mutation kind this writer does not apply yet, or when opts asks for something the log path does not combine with (included, or the per-edit vectors of the plain writer).