1 files changed, 29 insertions, 0 deletions
diff --git a/tests/snapshot_scroll_arena_test.c b/tests/snapshot_scroll_arena_test.c
new file mode 100644
index 0000000..7da6507
--- /dev/null
+++ b/tests/snapshot_scroll_arena_test.c
@@ -0,0 +1,29 @@
+/* Include snapshot.c to inspect its private arena accounting. The static
+ * library supplies the terminal implementation; this translation unit's
+ * snapshot symbols satisfy the test's references before the archive is read.
+ */
+#include <assert.h>
+#include "../src/snapshot.c"
+
+int main(void)
+{
+    struct term_options options = { .size = { 8, 24 }, .scrollback = 5 };
+    struct term *t = term_new(&options);
+    struct term_snapshot *s = term_snapshot_new();
+    assert(t && s && term_snapshot_update(s, t));
+
+    const char line[] = "e\xcc\x81\r\n";
+    for (int i = 0; i < 10000; i++) {
+        term_feed(t, line, sizeof(line) - 1, 0);
+        assert(term_snapshot_update(s, t));
+    }
+
+    /* A fixed viewport holds fewer than 24 * 8 cluster records at once.
+     * Dead records are compacted before they can dominate this arena. */
+    assert(term_history_rows(t) == 5);
+    assert(s->arena_len < 8192);
+
+    term_snapshot_free(s);
+    term_free(t);
+    return 0;
+}