tests: improve robustness of immediate successes in screen tests

test/functional/ui/output_spec.lua

@@ -51,25 +51,20 @@ describe("shell command :!", function()
   end)
 
   it("throttles shell-command output greater than ~10KB", function()
-    if os.getenv("TRAVIS") and helpers.os_name() == "osx" then
-      pending("[Unreliable on Travis macOS.]", function() end)
-      return
-    end
-
-    screen.timeout = 20000  -- Avoid false failure on slow systems.
     child_session.feed_data(
-      ":!for i in $(seq 2 3000); do echo XXXXXXXXXX $i; done\n")
+      ":!for i in $(seq 2 30000); do echo XXXXXXXXXX $i; done\n")
 
     -- If we observe any line starting with a dot, then throttling occurred.
-    screen:expect{any="\n."}
+    -- Avoid false failure on slow systems.
+    screen:expect{any="\n%.", timeout=20000}
 
     -- Final chunk of output should always be displayed, never skipped.
     -- (Throttling is non-deterministic, this test is merely a sanity check.)
     screen:expect([[
-      XXXXXXXXXX 2997                                   |
-      XXXXXXXXXX 2998                                   |
-      XXXXXXXXXX 2999                                   |
-      XXXXXXXXXX 3000                                   |
+      XXXXXXXXXX 29997                                  |
+      XXXXXXXXXX 29998                                  |
+      XXXXXXXXXX 29999                                  |
+      XXXXXXXXXX 30000                                  |
                                                         |
       {10:Press ENTER or type command to continue}{1: }          |
       {3:-- TERMINAL --}                                    |