Region scrolling tests

term/src/test/mod.rs

@@ -1181,6 +1181,114 @@ fn test_1573() {
     assert_eq!(graphemes, vec![sequence]);
 }
 
+#[test]
+fn test_region_scroll() {
+    let mut term = TestTerm::new(5, 1, 10);
+    term.print("1\n2\n3\n4\n5");
+
+    // Test scroll region that doesn't start on first row, scrollback not used
+    term.set_scroll_region(1, 2);
+    term.cup(0, 2);
+    let seqno = term.current_seqno();
+    term.print("\na");
+    assert_all_contents(&term, file!(), line!(), &["1", "3", "a", "4", "5"]);
+    term.assert_dirty_lines(seqno, &[1, 2], None);
+    assert_eq!(term.screen().visible_row_to_stable_row(0), 0);
+    assert_eq!(term.screen().visible_row_to_stable_row(4), 4);
+
+    // Scroll region starting on first row, but is smaller than screen (see #6099)
+    //  Scrollback will be used, which means lines below the scroll region
+    //  have their stable index invalidated, and so need to be marked dirty
+    term.set_scroll_region(0, 1);
+    term.cup(0, 1);
+    let seqno = term.current_seqno();
+    term.print("\nb");
+    assert_all_contents(&term, file!(), line!(), &["1", "3", "b", "a", "4", "5"]);
+    term.assert_dirty_lines(seqno, &[2, 3, 4, 5], None);
+    assert_eq!(term.screen().visible_row_to_stable_row(0), 1);
+    assert_eq!(term.screen().visible_row_to_stable_row(4), 5);
+
+    // Test deletion of more lines than exist in scroll region
+    term.cup(0, 1);
+    let seqno = term.current_seqno();
+    term.delete_lines(3);
+    assert_all_contents(&term, file!(), line!(), &["1", "3", "", "a", "4", "5"]);
+    term.assert_dirty_lines(seqno, &[2], None);
+    assert_eq!(term.screen().visible_row_to_stable_row(0), 1);
+    assert_eq!(term.screen().visible_row_to_stable_row(4), 5);
+
+    // Return to normal, entire-screen scrolling, optimal number of lines marked dirty
+    term.set_scroll_region(0, 4);
+    term.cup(0, 4);
+    let seqno = term.current_seqno();
+    term.print("\nX");
+    assert_all_contents(&term, file!(), line!(), &["1", "3", "", "a", "4", "5", "X"]);
+    term.assert_dirty_lines(seqno, &[6], None);
+    assert_eq!(term.screen().visible_row_to_stable_row(4), 6);
+}
+
+#[test]
+fn test_alt_screen_region_scroll() {
+    // Test that scrollback is never used, and lines below the scroll region
+    //  aren't made dirty or invalid. Only the scroll region is marked dirty.
+    let mut term = TestTerm::new(5, 1, 10);
+    term.print("M\no\nn\nk\ne\ny");
+
+    // Enter alternate-screen mode, saving current state
+    term.set_mode("?1049", true);
+    term.print("1\n2\n3\n4\n5");
+
+    // Test scroll region that doesn't start on first row
+    term.set_scroll_region(1, 2);
+    term.cup(0, 2);
+    let seqno = term.current_seqno();
+    term.print("\na");
+    assert_all_contents(&term, file!(), line!(), &["1", "3", "a", "4", "5"]);
+    term.assert_dirty_lines(seqno, &[1, 2], None);
+    assert_eq!(term.screen().visible_row_to_stable_row(4), 4);
+
+    // Test scroll region that starts on first row, still no scrollback
+    term.set_scroll_region(0, 1);
+    term.cup(0, 1);
+    let seqno = term.current_seqno();
+    term.print("\nb");
+    assert_all_contents(&term, file!(), line!(), &["3", "b", "a", "4", "5"]);
+    term.assert_dirty_lines(seqno, &[0, 1], None);
+    assert_eq!(term.screen().visible_row_to_stable_row(4), 4);
+
+    // Return to normal, entire-screen scrolling
+    //  Not optimal, the entire screen is marked dirty for every line scrolled
+    term.set_scroll_region(0, 4);
+    term.cup(0, 4);
+    let seqno = term.current_seqno();
+    term.print("\nX");
+    assert_all_contents(&term, file!(), line!(), &["b", "a", "4", "5", "X"]);
+    term.assert_dirty_lines(seqno, &[0, 1, 2, 3, 4], None);
+    assert_eq!(term.screen().visible_row_to_stable_row(4), 4);
+
+    // Leave alternate-mode and ensure screen is restored, with all lines marked dirty
+    let seqno = term.current_seqno();
+    term.set_mode("?1049", false);
+    assert_all_contents(&term, file!(), line!(), &["M", "o", "n", "k", "e", "y"]);
+    term.assert_dirty_lines(seqno, &[0, 1, 2, 3, 4], None);
+    assert_eq!(term.screen().visible_row_to_stable_row(0), 1);
+}
+
+#[test]
+fn test_region_scrollback_limit() {
+    // Ensure scrollback is truncated properly, when it reaches the line limit
+    let mut term = TestTerm::new(4, 1, 2);
+    term.print("1\n2\n3\n4");
+    term.set_scroll_region(0, 1);
+    term.cup(0, 1);
+
+    let seqno = term.current_seqno();
+    term.print("A\nB\nC\nD");
+    assert_all_contents(&term, file!(), line!(), &["A", "B", "C", "D", "3", "4"]);
+    term.assert_dirty_lines(seqno, &[0, 1, 2, 3, 4, 5], None);
+    assert_eq!(term.screen().visible_row_to_stable_row(4), 7);
+}
+
 #[test]
 fn test_hyperlinks() {
     let mut term = TestTerm::new(3, 5, 0);