Add tail option for expandedDisplay

Signed-off-by: Maxim Zhiburt <zhiburt@gmail.com>

src/display/expanded_display.rs

@@ -46,13 +46,21 @@ impl ExpandedDisplay {
 
     /// Sets max width of value.
     /// The rest will be trunceted.
-    pub fn truncate(&mut self, max: usize) -> &mut Self {
+    pub fn truncate(&mut self, max: usize, tail: impl AsRef<str>) -> &mut Self {
+        let tail = tail.as_ref().to_string();
         self.format_value = Some(Box::new(move |s| {
-            s.chars()
+            let mut s = s
+                .chars()
                 .take(max)
                 .collect::<String>()
                 .escape_debug()
-                .to_string()
+                .to_string();
+
+            if s.chars().count() >= max {
+                s.push_str(&tail);
+            }
+
+            s
         }));
         self
     }

tests/expanded_display_test.rs

@@ -323,7 +323,54 @@ fn display_with_truncate() {
         "link         | htt\n",
     );
 
-    let table = ExpandedDisplay::new(&data).truncate(3).to_string();
+    let table = ExpandedDisplay::new(&data).truncate(3, "").to_string();
+
+    assert_eq!(table, expected);
+}
+
+#[test]
+fn display_with_truncate_with_tail() {
+    #[derive(Tabled)]
+    struct Linux {
+        id: u8,
+        destribution: &'static str,
+        link: &'static str,
+    }
+
+    let data = vec![
+        Linux {
+            id: 0,
+            destribution: "Fedora",
+            link: "https://getfedora.org/",
+        },
+        Linux {
+            id: 2,
+            destribution: "OpenSUSE",
+            link: "https://www.opensuse.org/",
+        },
+        Linux {
+            id: 3,
+            destribution: "Endeavouros",
+            link: "https://endeavouros.com/",
+        },
+    ];
+
+    let expected = concat!(
+        "-[ RECORD 0 ]--------\n",
+        "id           | 0\n",
+        "destribution | Fed...\n",
+        "link         | htt...\n",
+        "-[ RECORD 1 ]--------\n",
+        "id           | 2\n",
+        "destribution | Ope...\n",
+        "link         | htt...\n",
+        "-[ RECORD 2 ]--------\n",
+        "id           | 3\n",
+        "destribution | End...\n",
+        "link         | htt...\n",
+    );
+
+    let table = ExpandedDisplay::new(&data).truncate(3, "...").to_string();
 
     assert_eq!(table, expected);
 }