pythongh-123856: Refactor isearch clean-up to call the existing clean…

…-up command; add tests

Lib/_pyrepl/simple_interact.py

@@ -160,9 +160,7 @@ def maybe_run_command(statement: str) -> bool:
         except KeyboardInterrupt:
             r = _get_reader()
             if r.input_trans is r.isearch_trans:
-                r.isearch_direction = ''
-                r.console.forgetinput()
-                r.pop_input_trans()
+                r.do_cmd(("isearch-end", ""))
             r.pos = len(r.get_unicode())
             r.dirty = True
             r.refresh()

Lib/test/test_pyrepl/test_pyrepl.py

@@ -8,6 +8,7 @@
 import subprocess
 import sys
 import tempfile
+import termios
 from unittest import TestCase, skipUnless
 from unittest.mock import patch
 from test.support import force_not_colorized
@@ -1246,6 +1247,12 @@ def _run_repl(
             env["PYTHON_HISTORY"] = os.path.join(cwd, ".regrtest_history")
         if cmdline_args is not None:
             cmd.extend(cmdline_args)
+
+        term_attr = termios.tcgetattr(slave_fd)
+        term_attr[6][termios.VREPRINT] = 0  # pass through CTRL-R
+        term_attr[6][termios.VINTR] = 0  # pass through CTRL-C
+        termios.tcsetattr(slave_fd, termios.TCSANOW, term_attr)
+
         process = subprocess.Popen(
             cmd,
             stdin=slave_fd,
@@ -1305,3 +1312,7 @@ def test_readline_history_file(self):
         output, exit_code = self.run_repl("exit\n", env=env)
         self.assertEqual(exit_code, 0)
         self.assertNotIn("\\040", pathlib.Path(hfile.name).read_text())
+
+    def test_keyboard_interrupt_after_isearch(self):
+        output, exit_code = self.run_repl(["\x12", "\x03", "exit"])
+        self.assertEqual(exit_code, 0)