1 files changed, 17 insertions, 0 deletions
diff --git a/test/functional/helpers.lua b/test/functional/helpers.lua
index 2472062d1e..272d2045c9 100644
--- a/test/functional/helpers.lua
+++ b/test/functional/helpers.lua
@@ -100,6 +100,22 @@ local function next_message()
   return session:next_message()
 end
 
+local function expect_twostreams(msgs1, msgs2)
+  local pos1, pos2 = 1, 1
+  while pos1 <= #msgs1 or pos2 <= #msgs2 do
+    local msg = next_message()
+    if pos1 <= #msgs1 and pcall(eq, msgs1[pos1], msg) then
+      pos1 = pos1 + 1
+    elseif pos2 <= #msgs2 then
+      eq(msgs2[pos2], msg)
+      pos2 = pos2 + 1
+    else
+      -- already failed, but show the right error message
+      eq(msgs1[pos1], msg)
+    end
+  end
+end
+
 local function call_and_stop_on_error(...)
   local status, result = copcall(...)  -- luacheck: ignore
   if not status then
@@ -663,6 +679,7 @@ local module = {
   command = nvim_command,
   request = request,
   next_message = next_message,
+  expect_twostreams = expect_twostreams,
   run = run,
   stop = stop,
   eq = eq,