pythongh-123856: Fix PyREPL failure when a keyboard interrupt is trig…

…gered after using a history search (pythonGH-124396)

(cherry picked from commit c1600c7)

Co-authored-by: Emily Morehouse <emily@cuttlesoft.com>
Co-authored-by: Łukasz Langa <lukasz@langa.pl>

Lib/_pyrepl/simple_interact.py

@@ -28,6 +28,7 @@
 import _sitebuiltins
 import linecache
 import functools
+import os
 import sys
 import code
 
@@ -50,7 +51,9 @@ def check() -> str:
     try:
         _get_reader()
     except _error as e:
-        return str(e) or repr(e) or "unknown error"
+        if term := os.environ.get("TERM", ""):
+            term = f"; TERM={term}"
+        return str(str(e) or repr(e) or "unknown error") + term
     return ""
 
 
@@ -159,10 +162,8 @@ def maybe_run_command(statement: str) -> bool:
             input_n += 1
         except KeyboardInterrupt:
             r = _get_reader()
-            if r.last_command and 'isearch' in r.last_command.__name__:
-                r.isearch_direction = ''
-                r.console.forgetinput()
-                r.pop_input_trans()
+            if r.input_trans is r.isearch_trans:
+                r.do_cmd(("isearch-end", [""]))
             r.pos = len(r.get_unicode())
             r.dirty = True
             r.refresh()

Lib/test/test_pyrepl/test_pyrepl.py

@@ -8,7 +8,7 @@
 import subprocess
 import sys
 import tempfile
-from unittest import TestCase, skipUnless
+from unittest import TestCase, skipUnless, skipIf
 from unittest.mock import patch
 from test.support import force_not_colorized
 from test.support import SHORT_TIMEOUT
@@ -35,6 +35,94 @@
 except ImportError:
     pty = None
 
+
+class ReplTestCase(TestCase):
+    def run_repl(
+        self,
+        repl_input: str | list[str],
+        env: dict | None = None,
+        *,
+        cmdline_args: list[str] | None = None,
+        cwd: str | None = None,
+    ) -> tuple[str, int]:
+        temp_dir = None
+        if cwd is None:
+            temp_dir = tempfile.TemporaryDirectory(ignore_cleanup_errors=True)
+            cwd = temp_dir.name
+        try:
+            return self._run_repl(
+                repl_input, env=env, cmdline_args=cmdline_args, cwd=cwd
+            )
+        finally:
+            if temp_dir is not None:
+                temp_dir.cleanup()
+
+    def _run_repl(
+        self,
+        repl_input: str | list[str],
+        *,
+        env: dict | None,
+        cmdline_args: list[str] | None,
+        cwd: str,
+    ) -> tuple[str, int]:
+        assert pty
+        master_fd, slave_fd = pty.openpty()
+        cmd = [sys.executable, "-i", "-u"]
+        if env is None:
+            cmd.append("-I")
+        elif "PYTHON_HISTORY" not in env:
+            env["PYTHON_HISTORY"] = os.path.join(cwd, ".regrtest_history")
+        if cmdline_args is not None:
+            cmd.extend(cmdline_args)
+
+        try:
+            import termios
+        except ModuleNotFoundError:
+            pass
+        else:
+            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,
+            stdout=slave_fd,
+            stderr=slave_fd,
+            cwd=cwd,
+            text=True,
+            close_fds=True,
+            env=env if env else os.environ,
+        )
+        os.close(slave_fd)
+        if isinstance(repl_input, list):
+            repl_input = "\n".join(repl_input) + "\n"
+        os.write(master_fd, repl_input.encode("utf-8"))
+
+        output = []
+        while select.select([master_fd], [], [], SHORT_TIMEOUT)[0]:
+            try:
+                data = os.read(master_fd, 1024).decode("utf-8")
+                if not data:
+                    break
+            except OSError:
+                break
+            output.append(data)
+        else:
+            os.close(master_fd)
+            process.kill()
+            self.fail(f"Timeout while waiting for output, got: {''.join(output)}")
+
+        os.close(master_fd)
+        try:
+            exit_code = process.wait(timeout=SHORT_TIMEOUT)
+        except subprocess.TimeoutExpired:
+            process.kill()
+            exit_code = process.wait()
+        return "".join(output), exit_code
+
+
 class TestCursorPosition(TestCase):
     def prepare_reader(self, events):
         console = FakeConsole(events)
@@ -968,7 +1056,20 @@ def test_bracketed_paste_single_line(self):
 
 
 @skipUnless(pty, "requires pty")
-class TestMain(TestCase):
+class TestDumbTerminal(ReplTestCase):
+    def test_dumb_terminal_exits_cleanly(self):
+        env = os.environ.copy()
+        env.update({"TERM": "dumb"})
+        output, exit_code = self.run_repl("exit()\n", env=env)
+        self.assertEqual(exit_code, 0)
+        self.assertIn("warning: can't use pyrepl", output)
+        self.assertNotIn("Exception", output)
+        self.assertNotIn("Traceback", output)
+
+
+@skipUnless(pty, "requires pty")
+@skipIf((os.environ.get("TERM") or "dumb") == "dumb", "can't use pyrepl in dumb terminal")
+class TestMain(ReplTestCase):
     def setUp(self):
         # Cleanup from PYTHON* variables to isolate from local
         # user settings, see #121359.  Such variables should be
@@ -1078,15 +1179,6 @@ def test_inspect_keeps_globals_from_inspected_module(self):
         }
         self._run_repl_globals_test(expectations, as_module=True)
 
-    def test_dumb_terminal_exits_cleanly(self):
-        env = os.environ.copy()
-        env.update({"TERM": "dumb"})
-        output, exit_code = self.run_repl("exit()\n", env=env)
-        self.assertEqual(exit_code, 0)
-        self.assertIn("warning: can't use pyrepl", output)
-        self.assertNotIn("Exception", output)
-        self.assertNotIn("Traceback", output)
-
     @force_not_colorized
     def test_python_basic_repl(self):
         env = os.environ.copy()
@@ -1209,80 +1301,6 @@ def test_proper_tracebacklimit(self):
                         self.assertIn("in x3", output)
                         self.assertIn("in <module>", output)
 
-    def run_repl(
-        self,
-        repl_input: str | list[str],
-        env: dict | None = None,
-        *,
-        cmdline_args: list[str] | None = None,
-        cwd: str | None = None,
-    ) -> tuple[str, int]:
-        temp_dir = None
-        if cwd is None:
-            temp_dir = tempfile.TemporaryDirectory(ignore_cleanup_errors=True)
-            cwd = temp_dir.name
-        try:
-            return self._run_repl(
-                repl_input, env=env, cmdline_args=cmdline_args, cwd=cwd
-            )
-        finally:
-            if temp_dir is not None:
-                temp_dir.cleanup()
-
-    def _run_repl(
-        self,
-        repl_input: str | list[str],
-        *,
-        env: dict | None,
-        cmdline_args: list[str] | None,
-        cwd: str,
-    ) -> tuple[str, int]:
-        assert pty
-        master_fd, slave_fd = pty.openpty()
-        cmd = [sys.executable, "-i", "-u"]
-        if env is None:
-            cmd.append("-I")
-        elif "PYTHON_HISTORY" not in env:
-            env["PYTHON_HISTORY"] = os.path.join(cwd, ".regrtest_history")
-        if cmdline_args is not None:
-            cmd.extend(cmdline_args)
-        process = subprocess.Popen(
-            cmd,
-            stdin=slave_fd,
-            stdout=slave_fd,
-            stderr=slave_fd,
-            cwd=cwd,
-            text=True,
-            close_fds=True,
-            env=env if env else os.environ,
-        )
-        os.close(slave_fd)
-        if isinstance(repl_input, list):
-            repl_input = "\n".join(repl_input) + "\n"
-        os.write(master_fd, repl_input.encode("utf-8"))
-
-        output = []
-        while select.select([master_fd], [], [], SHORT_TIMEOUT)[0]:
-            try:
-                data = os.read(master_fd, 1024).decode("utf-8")
-                if not data:
-                    break
-            except OSError:
-                break
-            output.append(data)
-        else:
-            os.close(master_fd)
-            process.kill()
-            self.fail(f"Timeout while waiting for output, got: {''.join(output)}")
-
-        os.close(master_fd)
-        try:
-            exit_code = process.wait(timeout=SHORT_TIMEOUT)
-        except subprocess.TimeoutExpired:
-            process.kill()
-            exit_code = process.wait()
-        return "".join(output), exit_code
-
     def test_readline_history_file(self):
         # skip, if readline module is not available
         readline = import_module('readline')
@@ -1305,3 +1323,7 @@ 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)

Misc/NEWS.d/next/Core_and_Builtins/2024-09-23-15-23-14.gh-issue-123856.yrgJ9m.rst

@@ -0,0 +1,2 @@
+Fix PyREPL failure when a keyboard interrupt is triggered after using a
+history search