Detect cross-line feedback migration

2 files changed, 51 insertions, 0 deletions

diff --git a/lua/clever_f/feedback_service.lua b/lua/clever_f/feedback_service.lua
index 6972d70..e553cd7 100644
--- a/lua/clever_f/feedback_service.lua
+++ b/lua/clever_f/feedback_service.lua
@@ -25,6 +25,10 @@ M.FinalizerAction = {
   PRESERVE = "preserve",
   FINALIZE = "finalize",
 }
+M.MigrationReason = {
+  LINE_CHANGE = "line_change",
+  TILL_DIRECTION_CHANGE = "till_direction_change",
+}
 
 local OVERLAY_PRIORITIES = {
   CleverFCursor = M.Priority.HIGH,
@@ -603,6 +607,28 @@ function FeedbackService:persistent_requests()
   return result
 end
 
+function M.command_migration_reason(request)
+  if type(request) ~= "table" then
+    fail("command feedback migration request must be a table", 2)
+  end
+  local origin = domain.Position.coerce(request.origin)
+  local destination = domain.Position.coerce(request.destination)
+  if request.outcome ~= nil and request.outcome.complete ~= true then
+    return nil
+  end
+  if origin.line ~= destination.line then
+    return M.MigrationReason.LINE_CHANGE
+  end
+  return nil
+end
+
+function FeedbackService:migrate_command(request)
+  return {
+    migrated = false,
+    reason = M.command_migration_reason(request),
+  }
+end
+
 function FeedbackService:evaluate_feature_links()
   local record = service_records[self]
   local rules = record.policy:evaluate_highlight_links()
diff --git a/tests/run.lua b/tests/run.lua
index b0f9cee..e73dda7 100644
--- a/tests/run.lua
+++ b/tests/run.lua
@@ -6374,6 +6374,31 @@ test("Full feedback finalization preserves reusable sequence data", function()
   same(dictionary, state:get_migemo("utf-8"))
 end)
 
+test("Command feedback migration compares origin and destination lines", function()
+  same(
+    nil,
+    feedback_service.command_migration_reason({
+      origin = domain.Position.new(2, 1),
+      destination = domain.Position.new(2, 7),
+    })
+  )
+  same(
+    feedback_service.MigrationReason.LINE_CHANGE,
+    feedback_service.command_migration_reason({
+      origin = domain.Position.new(2, 7),
+      destination = domain.Position.new(3, 1),
+    })
+  )
+  same(
+    nil,
+    feedback_service.command_migration_reason({
+      origin = domain.Position.new(2, 7),
+      destination = domain.Position.new(3, 1),
+      outcome = { complete = false },
+    })
+  )
+end)
+
 for _, item in ipairs(tests) do
   local ok, failure = xpcall(item.body, debug.traceback)
   if not ok then