feat(cli): Add utility function for getting a LevelFilter from verbosity

src/cli.rs

@@ -76,3 +76,29 @@ fn try_init_pretty_logger(
 
     builder.try_init()
 }
+
+/// Converts a integer verbosity value into a `LevelFilter`.
+///
+/// Examples:
+///
+/// ```
+/// use collective::cli::get_log_level_filter_from_verbosity;
+///
+/// assert_eq!(
+///     get_log_level_filter_from_verbosity(1),
+///     Some(log::LevelFilter::Info)
+/// );
+///
+/// assert_eq!(
+///     get_log_level_filter_from_verbosity(15),
+///     None
+/// );
+/// ```
+pub fn get_log_level_filter_from_verbosity(verbosity: u8) -> Option<log::LevelFilter> {
+    match verbosity {
+        3 => Some(log::LevelFilter::Trace),
+        2 => Some(log::LevelFilter::Debug),
+        1 => Some(log::LevelFilter::Info),
+        _ => None,
+    }
+}