pub fn gitignore_with_log_rule(existing: Option<&str>) -> Option<String>Expand description
Given a .ct/.gitignore’s current contents (or None when it is absent),
return the contents to write so it carries LOG_IGNORE_RULE, or None
when the rule is already present (no write needed). Existing lines are
preserved; the rule is appended.
§Examples
use coding_tools::steer::gitignore_with_log_rule;
assert_eq!(gitignore_with_log_rule(None).as_deref(), Some("*log\n"));
assert_eq!(gitignore_with_log_rule(Some("*log\n")), None); // already there
assert_eq!(gitignore_with_log_rule(Some("target\n")).as_deref(), Some("target\n*log\n"));