add unit tests and render test for tab handling

src/style.rs

@@ -770,4 +770,66 @@ mod tests {
         style.format_state(&state, &mut buf, WIDTH);
         assert_eq!(&buf[0], "fghijklmno");
     }
+
+    #[test]
+    fn tab_expansion_basics() {
+        const WIDTH: u16 = 20;
+        let pos = Arc::new(AtomicPosition::new());
+        let state = ProgressState::new(Some(10), pos);
+        let mut buf = Vec::new();
+
+        let mut style = ProgressStyle::default_spinner();
+        style.message = "a\ttest".into();
+        style.format_state(&state, &mut buf, WIDTH);
+        assert_eq!(&buf[0], "⠁ a    test");
+
+        style.tab_width = 8;
+        buf.clear();
+        style.format_state(&state, &mut buf, WIDTH);
+        assert_eq!(&buf[0], "⠁ a        test");
+    }
+
+    #[test]
+    fn tab_expansion_wide_msg() {
+        const WIDTH: u16 = 20;
+        let pos = Arc::new(AtomicPosition::new());
+        let state = ProgressState::new(Some(10), pos);
+        let mut buf = Vec::new();
+
+        let mut style = ProgressStyle::with_template("{wide_msg}").unwrap();
+        style.message = "abc\tdefghijklmnopqrst".into();
+        style.format_state(&state, &mut buf, WIDTH);
+        assert_eq!(&buf[0], "abc    defghijklmnop");
+
+        buf.clear();
+        let mut style = ProgressStyle::with_template("{wide_msg:>}").unwrap();
+        style.message = "abc\tdefghijklmnopqrst".into();
+        style.format_state(&state, &mut buf, WIDTH);
+        assert_eq!(&buf[0], "   defghijklmnopqrst");
+
+        buf.clear();
+        let mut style = ProgressStyle::with_template("{wide_msg:^}").unwrap();
+        style.message = "abc\tdefghijklmnopqrst".into();
+        style.format_state(&state, &mut buf, WIDTH);
+        assert_eq!(&buf[0], "c    defghijklmnopqr");
+    }
+
+    #[test]
+    fn tab_expansion_multiple() {
+        const WIDTH: u16 = 20;
+        let pos = Arc::new(AtomicPosition::new());
+        let state = ProgressState::new(Some(10), pos);
+        let mut buf = Vec::new();
+
+        let mut style = ProgressStyle::with_template("\top: {wide_msg}").unwrap();
+        style.message = "abc\tdefghijklmnopqrst".into();
+        style.format_state(&state, &mut buf, WIDTH);
+        assert_eq!(&buf[0], "    op: abc    defgh");
+
+        buf.clear();
+        let mut style = ProgressStyle::with_template("{msg}:\t{wide_bar}").unwrap();
+        style.message = "\tOP".into();
+        style.format_state(&state, &mut buf, WIDTH);
+        assert_eq!(&buf[0], "    OP:    ░░░░░░░░░");
+    }
 }

tests/render.rs

@@ -270,3 +270,38 @@ fn ticker_drop() {
         "  doing stuff 0\n  doing stuff 1\n  doing stuff 2\n  doing stuff 3\n  doing stuff 4"
     );
 }
+
+#[test]
+fn multi_with_tabs() {
+    let in_mem = InMemoryTerm::new(10, 80);
+    let mp =
+        MultiProgress::with_draw_target(ProgressDrawTarget::term_like(Box::new(in_mem.clone())));
+
+    let overall_progress = mp.add(ProgressBar::new(10).with_message("overall"));
+
+    let spinner = mp.insert_before(
+        &overall_progress,
+        ProgressBar::new_spinner()
+            .with_finish(ProgressFinish::AndLeave)
+            .with_message("spinning"),
+    );
+    spinner.tick();
+
+    assert_eq!(in_mem.contents(), "⠁ spinning");
+    assert_eq!(in_mem.cursor_pos(), (0, 80));
+
+    let msg1 = mp.insert_after(
+        &spinner,
+        ProgressBar::new_spinner()
+            .with_finish(ProgressFinish::AndLeave)
+            .with_message("\tmessage!"),
+    );
+
+    msg1.tick();
+    assert_eq!(in_mem.contents(), "⠁ spinning\n⠁     message!");
+    // If tabs are being handled correctly, the cursor should be at the end of the last line.
+    assert_eq!(in_mem.cursor_pos(), (1, 80));
+
+    overall_progress.inc(1);
+    assert_eq!(in_mem.contents(), "⠁ spinning\n⠁     message!\n███████░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░ 1/10");
+}