Function locate_template 

pub fn locate_template(
    source: &dyn TemplateSource,
    cli_path: Option<&Path>,
    max: usize,
) -> Result<Template, TemplateError>

Finds the template: the command-line path, then the first existing candidate, then the built-in template.

Errors

TemplateError::Unreadable when the command-line path cannot be read or holds more than max bytes, with no fallback, and TemplateError::Missing when no step supplies a template. A candidate over max bytes is passed over.