1 files changed, 25 insertions, 0 deletions
diff --git a/tests/run.lua b/tests/run.lua
index 4984fb6..718488b 100644
--- a/tests/run.lua
+++ b/tests/run.lua
@@ -4710,6 +4710,31 @@ test("Smart-case previews add ASCII uppercase to lowercase counters", function()
   falsy(direct_preview_planner.is_upper_ascii("AA"))
 end)
 
+test("Smart-case previews mark the exact and lowercase union", function()
+  local planner = direct_preview_planner.new({ lowercase = string.lower })
+  local origin = domain.Position.new(1, 1)
+
+  local folded_position = planner:plan(
+    text_topology.new({ "xaA" }, "utf-8"),
+    origin,
+    "f",
+    2,
+    { ignore_case = false, smart_case = true }
+  )
+  same(1, #folded_position)
+  same(domain.Position.new(1, 3), folded_position[1])
+
+  local one_marker = planner:plan(
+    text_topology.new({ "xAA" }, "utf-8"),
+    origin,
+    "f",
+    2,
+    { ignore_case = false, smart_case = true }
+  )
+  same(1, #one_marker)
+  same(domain.Position.new(1, 3), one_marker[1])
+end)
+
 for _, item in ipairs(tests) do
   local ok, failure = xpcall(item.body, debug.traceback)
   if not ok then