fix: make two installer tests runner-proof

The old-card test read the screen without reading what the key just drew, and pressed Enter twelve rows past its folder on a slow runner. The launcher device now has a sudo that refuses, as a runner's passwordless sudo ran the fake mapper as root and recorded nothing.

tests/test_handheld_launchers.py

@@ -677,6 +677,10 @@ class Device:
         # A probe that cannot connect is offline (curl exit 7).
         self.tool("curl", '#!/bin/sh\nexit "${FAKE_CURL:-0}"\n')
         self.tool("pgrep", '#!/bin/sh\nexit "${FAKE_PGREP:-1}"\n')
+        # A runner's real sudo needs no password: the Tools entry then ran
+        # the fake mapper as root, with a reset environment, and recorded
+        # nothing. A device has no sudo unless a test gives it one.
+        self.tool("sudo", "#!/bin/sh\nexit 1\n")
         fonts = self.root / "fonts"
         fonts.mkdir()
         for name in ("Lat7-TerminusBold32x16", "Lat7-TerminusBold22x11",

tests/test_install_tui.py

@@ -2818,6 +2818,21 @@ class Pty:
     def text(self) -> str:
         return "\n".join(line.rstrip() for line in self.screen.display)
 
+    def settle(self, quiet: float = 0.3, timeout: float = 10.0) -> str:
+        """The screen once nothing more arrives for `quiet` seconds.
+
+        text() shows only what was read: a loop that sent a key and looked
+        again saw the screen before the key, and on a slow runner pressed
+        Enter twelve rows past the folder it was looking for.
+        """
+        end = time.monotonic() + timeout
+        while time.monotonic() < end:
+            if not select.select([self.fd], [], [], quiet)[0]:
+                break
+            if not self._pump(0):
+                break
+        return self.text()
+
     def wait(self, needle: str, timeout: float = 20.0) -> str:
         end = time.monotonic() + timeout
         while time.monotonic() < end:
@@ -3124,9 +3139,10 @@ class EndToEnd(unittest.TestCase):
         term.send(DOWN, DOWN, "\r")
         term.wait("Choose the old card")
         for _ in range(12):
-            if "> oldcard/" in term.text():
+            if "> oldcard/" in term.settle():
                 break
             term.send(DOWN)
+        self.assertIn("> oldcard/", term.settle())
         term.send("\r")
         term.wait("> Use this folder")
         term.send("\r")