feat: improve list view

src/backup/delta.rs

@@ -1,5 +1,6 @@
 use serde::{Deserialize, Serialize};
 use std::collections::{HashMap, HashSet};
+use std::fmt;
 use std::path::PathBuf;
 
 /// Represents the changes relative to the previous backup
@@ -74,3 +75,12 @@ impl Delta {
         }
     }
 }
+
+impl fmt::Display for Delta {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let added_count: usize = self.added.values().map(|s| s.len()).sum();
+        let removed_count: usize = self.removed.values().map(|s| s.len()).sum();
+
+        write!(f, "+{}-{}", added_count, removed_count)
+    }
+}

src/backup/mod.rs

@@ -14,6 +14,7 @@ use flate2::Compression;
 use path::PathExt;
 use serde::{Deserialize, Serialize};
 use std::collections::{HashMap, HashSet};
+use std::fmt;
 use std::fs::File;
 use std::io;
 use std::path::{Path, PathBuf};
@@ -205,3 +206,20 @@ impl<T: Clone> Backup<T> {
         Ok(())
     }
 }
+
+impl<T: Clone> fmt::Display for Backup<T> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let letter = match self.type_ {
+            BackupType::Full => 'F',
+            BackupType::Incremental => 'I',
+        };
+
+        write!(
+            f,
+            "{} ({}, {})",
+            self.start_time.format(Backup::FILENAME_FORMAT),
+            letter,
+            self.delta
+        )
+    }
+}

src/cli/backup.rs

@@ -136,11 +136,10 @@ impl BackupListArgs {
 
             for chain in manager.chains().iter().filter(|c| !c.is_empty()) {
                 let mut iter = chain.iter();
-                let first = iter.next().unwrap();
-                println!("  {}", first.start_time.format(Backup::FILENAME_FORMAT));
+                println!("  {}", iter.next().unwrap());
 
                 for backup in iter {
-                    println!("    {}", backup.start_time.format(Backup::FILENAME_FORMAT));
+                    println!("    {}", backup);
                 }
             }
         }