commit fe354d70d4ad218c599cac447058537d734836e5
from: Mark Jamsek <mark@jamsek.dev>
via: Thomas Adam <thomas@xteddy.org>
date: Fri Jan  3 10:46:48 2025 UTC

tog: clamp selected idx to avoid showing negative indexes

In the rare case views are smaller in height than the first line number
after the view's header lines (i.e., [2,5] depending on the view), we can
decrement the selected entry index into negative values; clamp it to 0.
Add a log view test case covering this path by opening a child tree view
and toggling fullscreen.

ok stsp@

commit - 9976affb503011ab063f1de78688b26414d8ec9a
commit + fe354d70d4ad218c599cac447058537d734836e5
blob - 01a33201435af4ba4c618c10db784372be30bea2
blob + 77e67c8632bd152393715a611f8d74a820e0e3c5
--- regress/tog/log.sh
+++ regress/tog/log.sh
@@ -1101,7 +1101,39 @@ test_log_worktree_entries()
 
 	test_done "$testroot" 0
 }
+
+test_log_tiny_child_tree_view()
+{
+	test_init log_tiny_child_tree_view 120 3
+
+	local id=$(git_show_head $testroot/repo)
+
+	# This test covers the offset_selection_down() path ensuring
+	# indexes are properly clamped to prevent negative values.
+	cat <<-EOF >$TOG_TEST_SCRIPT
+	T		open tree view in vsplit
+	F		toggle fullscreen to hit offset_selection_down()
+	SCREENDUMP
+	EOF
 
+	cat <<-EOF >$testroot/view.expected
+	commit $id
+	[1/4] /
+
+	EOF
+
+	cd $testroot/repo && tog log
+	cmp -s $testroot/view.expected $testroot/view
+	ret=$?
+	if [ $ret -ne 0 ]; then
+		diff -u $testroot/view.expected $testroot/view
+		test_done "$testroot" "$ret"
+		return 1
+	fi
+
+	test_done "$testroot" "$ret"
+}
+
 test_parseargs "$@"
 run_test test_log_hsplit_diff
 run_test test_log_vsplit_diff
@@ -1116,3 +1148,4 @@ run_test test_log_limit_view
 run_test test_log_search
 run_test test_log_mark_keymap
 run_test test_log_worktree_entries
+run_test test_log_tiny_child_tree_view
blob - 879259f6229b008b4113a82b1138cd2193670ee0
blob + 2f26d13b606488dfcb50b4273bb71e143d93b757
--- tog/tog.c
+++ tog/tog.c
@@ -11469,7 +11469,7 @@ offset_selection_down(struct tog_view *view)
 		view->offset = offset;
 		if (scrolld && offset) {
 			err = scrolld(view, offset);
-			*selected -= offset;
+			*selected -= MIN(*selected, offset);
 		}
 	}