1 files changed, 177 insertions, 0 deletions
diff --git a/t/21shift-bottom.t b/t/21shift-bottom.t
new file mode 100644
index 0000000..22ef5a7
--- /dev/null
+++ b/t/21shift-bottom.t
@@ -0,0 +1,177 @@
+#!/usr/bin/perl
+
+use strict;
+use warnings;
+
+use Test::More;
+
+use Tickit::Test 0.12;
+
+use Tickit::Widget::Scroller;
+use Tickit::Widget::Scroller::Item::Text;
+
+# TODO: mk_window once Tickit::Test can take a size there too
+my ( $term, $rootwin ) = mk_term_and_window cols => 20, lines => 8;
+my $win = $rootwin->make_sub( 0, 0, 6, 20 );
+
+$rootwin->focus( 7, 0 );
+
+my $scroller = Tickit::Widget::Scroller->new(
+   gravity => "bottom",
+);
+
+$scroller->push(
+   Tickit::Widget::Scroller::Item::Text->new( "Existing line $_" ),
+) for 1 .. 20;
+
+$scroller->set_window( $win );
+
+flush_tickit;
+
+is_termlog( [ ( map { GOTO($_-1,0),
+                      SETPEN,
+                      PRINT("Existing line $_"),
+                      SETBG(undef),
+                      ERASECH(5) } 1 .. 6 ),
+              GOTO(7,0) ],
+            'Termlog initially' );
+
+is_display( [ [TEXT("Existing line 1")],
+              [TEXT("Existing line 2")],
+              [TEXT("Existing line 3")],
+              [TEXT("Existing line 4")],
+              [TEXT("Existing line 5")],
+              [TEXT("Existing line 6")] ],
+            'Display initially' );
+
+is_cursorpos( 7, 0, 'Cursor position intially' );
+
+$scroller->shift;
+
+flush_tickit;
+
+is_termlog( [ SETBG(undef),
+              SCROLLRECT(0,0,6,20, 1,0),
+              GOTO(5,0),
+              SETPEN,
+              PRINT("Existing line 7"),
+              SETBG(undef),
+              ERASECH(5),
+              GOTO(7,0) ],
+            'Termlog after shift' );
+
+is_display( [ [TEXT("Existing line 2")],
+              [TEXT("Existing line 3")],
+              [TEXT("Existing line 4")],
+              [TEXT("Existing line 5")],
+              [TEXT("Existing line 6")],
+              [TEXT("Existing line 7")] ],
+            'Display after shift' );
+
+is_cursorpos( 7, 0, 'Cursor position after shift' );
+
+$scroller->shift( 3 );
+
+flush_tickit;
+
+is_termlog( [ SETBG(undef),
+              SCROLLRECT(0,0,6,20, 3,0),
+              GOTO(3,0),
+              SETPEN,
+              PRINT("Existing line 8"),
+              SETBG(undef),
+              ERASECH(5),
+              GOTO(4,0),
+              SETPEN,
+              PRINT("Existing line 9"),
+              SETBG(undef),
+              ERASECH(5),
+              GOTO(5,0),
+              SETPEN,
+              PRINT("Existing line 10"),
+              SETBG(undef),
+              ERASECH(4),
+              GOTO(7,0) ],
+            'Termlog after shift 3' );
+
+is_display( [ [TEXT("Existing line 5")],
+              [TEXT("Existing line 6")],
+              [TEXT("Existing line 7")],
+              [TEXT("Existing line 8")],
+              [TEXT("Existing line 9")],
+              [TEXT("Existing line 10")] ],
+            'Display after shift 3' );
+
+is_cursorpos( 7, 0, 'Cursor position after shift 3' );
+
+$scroller->scroll_to_bottom;
+flush_tickit;
+drain_termlog;
+
+is_display( [ [TEXT("Existing line 15")],
+              [TEXT("Existing line 16")],
+              [TEXT("Existing line 17")],
+              [TEXT("Existing line 18")],
+              [TEXT("Existing line 19")],
+              [TEXT("Existing line 20")] ],
+            'Display after scroll_to_bottom' );
+
+$scroller->shift;
+
+flush_tickit;
+
+is_termlog( [],
+            'Termlog empty after shift at bottom' );
+
+is_display( [ [TEXT("Existing line 15")],
+              [TEXT("Existing line 16")],
+              [TEXT("Existing line 17")],
+              [TEXT("Existing line 18")],
+              [TEXT("Existing line 19")],
+              [TEXT("Existing line 20")] ],
+            'Display unchanged after shift at bottom' );
+
+$scroller->scroll_to_top;
+flush_tickit;
+drain_termlog;
+
+is_display( [ [TEXT("Existing line 6")],
+              [TEXT("Existing line 7")],
+              [TEXT("Existing line 8")],
+              [TEXT("Existing line 9")],
+              [TEXT("Existing line 10")],
+              [TEXT("Existing line 11")] ],
+            'Display after scroll_to_top' );
+
+$scroller->shift( 6 );
+
+flush_tickit;
+
+is_termlog( [ ( map { GOTO($_-12,0),
+                      SETPEN,
+                      PRINT("Existing line $_"),
+                      SETBG(undef),
+                      ERASECH(4) } 12 .. 17 ),
+              GOTO(7,0) ],
+            'Termlog after shift 6 at top' );
+
+is_display( [ [TEXT("Existing line 12")],
+              [TEXT("Existing line 13")],
+              [TEXT("Existing line 14")],
+              [TEXT("Existing line 15")],
+              [TEXT("Existing line 16")],
+              [TEXT("Existing line 17")] ],
+            'Display after shift 6 at top' );
+
+$scroller->shift( 4 );
+
+flush_tickit;
+
+is_display( [ [TEXT("Existing line 16")],
+              [TEXT("Existing line 17")],
+              [TEXT("Existing line 18")],
+              [TEXT("Existing line 19")],
+              [TEXT("Existing line 20")] ],
+            'Display after shift to expose bottom' );
+
+done_testing;