fix: tabs would not be rendered, render them as 4 spaces for now

closes: #201

src/items.rs

@@ -100,7 +100,7 @@ fn format_diff_hunk_items(depth: usize, hunk: Rc<Hunk>) -> Vec<Item> {
         .iter()
         .enumerate()
         .map(|(i, line)| Item {
-            display: line.clone(),
+            display: replace_tabs_with_spaces(line.clone()),
             unselectable: line
                 .spans
                 .first()
@@ -112,6 +112,17 @@ fn format_diff_hunk_items(depth: usize, hunk: Rc<Hunk>) -> Vec<Item> {
         .collect()
 }
 
+fn replace_tabs_with_spaces(line: Line<'_>) -> Line<'_> {
+    let spans = line
+        .spans
+        .iter()
+        .cloned()
+        .map(|span| Span::styled(span.content.replace('\t', "    "), span.style))
+        .collect::<Vec<_>>();
+
+    Line { spans, ..line }
+}
+
 pub(crate) fn stash_list(config: &Config, repo: &Repository, limit: usize) -> Res<Vec<Item>> {
     let style = &config.style;
 

src/tests/mod.rs

@@ -351,3 +351,15 @@ fn crlf_diff() {
 
     insta::assert_snapshot!(ctx.redact_buffer());
 }
+
+#[test]
+fn tab_diff() {
+    let mut ctx = TestContext::setup_init();
+    let mut state = ctx.init_state();
+
+    commit(ctx.dir.path(), "tab.txt", "this has no tab prefixed\n");
+    fs::write(ctx.dir.child("tab.txt"), "\tthis has a tab prefixed\n").unwrap();
+    state.update(&mut ctx.term, &keys("g")).unwrap();
+
+    insta::assert_snapshot!(ctx.redact_buffer());
+}

src/tests/snapshots/gitu__tests__tab_diff.snap

@@ -0,0 +1,25 @@
+---
+source: src/tests/mod.rs
+expression: ctx.redact_buffer()
+---
+▌On branch main                                                                 |
+                                                                                |
+ Unstaged changes (1)                                                           |
+ modified   tab.txt                                                             |
+ @@ -1 +1 @@                                                                    |
+ -this has no tab prefixed                                                      |
+ +    this has a tab prefixed                                                   |
+                                                                                |
+ Recent commits                                                                 |
+ _______ main add tab.txt                                                       |
+                                                                                |
+                                                                                |
+                                                                                |
+                                                                                |
+                                                                                |
+                                                                                |
+                                                                                |
+                                                                                |
+                                                                                |
+                                                                                |
+styles_hash: 4c33c9d79050f1a0