Less verbose cache age formatting (#849)

Previously the cache age was formatted with nanosecond resolution,
which is too fine-grained even for Rustaceans.
Now the format is limited to days, hours, minutes, and seconds.
With that, the cache age becomes more easily parseable by humans.

lychee-bin/src/formatters/duration.rs

@@ -0,0 +1,74 @@
+use std::fmt;
+
+/// Wrapper struct around `elapsed.as_secs()` for custom formatting.
+///
+/// # Examples
+///
+/// ```
+/// use lychee_bin::formatters::Duration;
+///
+/// let duration = Duration::from_secs(1);
+/// assert_eq!(duration.to_string(), "1s");
+///
+/// let duration = Duration::from_secs(60);
+/// assert_eq!(duration.to_string(), "1m");
+///
+/// let duration = Duration::from_secs(61);
+/// assert_eq!(duration.to_string(), "1m 1s");
+///
+/// let duration = Duration::from_secs(3661);
+/// assert_eq!(duration.to_string(), "1h 1m 1s");
+/// ```
+pub(crate) struct Duration {
+    elapsed: u64,
+}
+
+impl Duration {
+    /// Create a new `Duration` from the given number of seconds.
+    pub(crate) const fn from_secs(elapsed: u64) -> Self {
+        Self { elapsed }
+    }
+}
+
+impl fmt::Display for Duration {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let days = self.elapsed / 86400;
+        let hours = (self.elapsed % 86400) / 3600;
+        let minutes = (self.elapsed % 3600) / 60;
+        let seconds = self.elapsed % 60;
+
+        if days > 0 {
+            write!(f, "{}d {}h {}m {}s", days, hours, minutes, seconds)
+        } else if hours > 0 {
+            write!(f, "{}h {}m {}s", hours, minutes, seconds)
+        } else if minutes > 0 {
+            write!(f, "{}m {}s", minutes, seconds)
+        } else {
+            write!(f, "{}s", seconds)
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_formatting() {
+        let duration = Duration::from_secs(61);
+        assert_eq!(duration.to_string(), "1m 1s");
+
+        let duration = Duration::from_secs(3661);
+        assert_eq!(duration.to_string(), "1h 1m 1s");
+
+        let duration = Duration::from_secs(90061);
+        assert_eq!(duration.to_string(), "1d 1h 1m 1s");
+
+        let duration = Duration::from_secs(0);
+        assert_eq!(duration.to_string(), "0s");
+
+        // 100 years printed as days
+        let duration = Duration::from_secs(3_153_600_000);
+        assert_eq!(duration.to_string(), "36500d 0h 0m 0s");
+    }
+}

lychee-bin/src/formatters/mod.rs

@@ -1,3 +1,4 @@
+pub(crate) mod duration;
 pub(crate) mod response;
 pub(crate) mod stats;
 

lychee-bin/src/main.rs

@@ -85,6 +85,7 @@ mod stats;
 mod time;
 mod verbosity;
 
+use crate::formatters::duration::Duration;
 use crate::{
     cache::{Cache, StoreExt},
     color::color,
@@ -191,15 +192,15 @@ fn load_cache(cfg: &Config) -> Option<Cache> {
             if elapsed > cfg.max_cache_age {
                 warn!(
                     "Cache is too old (age: {}, max age: {}). Discarding and recreating.",
-                    humantime::format_duration(elapsed),
-                    humantime::format_duration(cfg.max_cache_age)
+                    Duration::from_secs(elapsed.as_secs()),
+                    Duration::from_secs(cfg.max_cache_age.as_secs())
                 );
                 return None;
             }
             info!(
                 "Cache is recent (age: {}, max age: {}). Using.",
-                humantime::format_duration(elapsed),
-                humantime::format_duration(cfg.max_cache_age)
+                Duration::from_secs(elapsed.as_secs()),
+                Duration::from_secs(cfg.max_cache_age.as_secs())
             );
         }
     }