gh-140287: Handle PYTHONSTARTUP script exceptions in the asyncio REPL

Lib/asyncio/__main__.py

@@ -101,7 +101,12 @@ def run(self):
  import tokenize
  with tokenize.open(startup_path) as f:
  startup_code = compile(f.read(), startup_path, "exec")
- exec(startup_code, console.locals)
+ try:
+ exec(startup_code, console.locals)
+ except SystemExit:
+ raise
+ except BaseException:
+ console.showtraceback()
 
  ps1 = getattr(sys, "ps1", ">>> ")
  if CAN_USE_PYREPL:

Lib/test/test_repl.py

@@ -5,6 +5,7 @@
 import subprocess
 import sys
 import unittest
+from contextlib import contextmanager
 from functools import partial
 from textwrap import dedent
 from test import support
@@ -28,7 +29,7 @@
  raise unittest.SkipTest("test module requires subprocess")
 
 
-def spawn_repl(*args, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, custom=False, **kw):
+def spawn_repl(*args, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, custom=False, isolated=True, **kw):
  """Run the Python REPL with the given arguments.
 
  kw is extra keyword args to pass to subprocess.Popen. Returns a Popen
@@ -42,7 +43,10 @@ def spawn_repl(*args, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, custom=F
  # path may be used by PyConfig_Get("module_search_paths") to build the
  # default module search path.
  stdin_fname = os.path.join(os.path.dirname(sys.executable), "<stdin>")
- cmd_line = [stdin_fname, '-I']
+ cmd_line = [stdin_fname]
+ # Isolated mode implies -EPs and ignores PYTHON* variables.
+ if isolated:
+ cmd_line.append('-I')
  # Don't re-run the built-in REPL from interactive mode
  # if we're testing a custom REPL (such as the asyncio REPL).
  if not custom:
@@ -64,6 +68,16 @@ def spawn_repl(*args, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, custom=F
 spawn_asyncio_repl = partial(spawn_repl, "-m", "asyncio", custom=True)
 
 
+@contextmanager
+def new_startup_env(*, code: str, histfile: str = ".pythonhist"):
+ """Create environment variables for a PYTHONSTARTUP script in a temporary directory."""
+ with os_helper.temp_dir() as tmpdir:
+ filename = os.path.join(tmpdir, "pythonstartup.py")
+ with open(filename, "w") as f:
+ f.write('\n'.join(code.splitlines()))
+ yield {"PYTHONSTARTUP": filename, "PYTHON_HISTORY": os.path.join(tmpdir, histfile)}
+
+
 def run_on_interactive_mode(source):
  """Spawn a new Python interpreter, pass the given
  input source code from the stdin and return the
@@ -197,68 +211,6 @@ def foo(x):
  ]
  self.assertEqual(traceback_lines, expected_lines)
 
- def test_pythonstartup_error_reporting(self):
- # errors based on https://github.com/python/cpython/issues/137576
-
- def make_repl(env):
- return subprocess.Popen(
- [os.path.join(os.path.dirname(sys.executable), '<stdin>'), "-i"],
- executable=sys.executable,
- text=True,
- stdin=subprocess.PIPE,
- stdout=subprocess.PIPE,
- stderr=subprocess.STDOUT,
- env=env,
- )
-
- # case 1: error in user input, but PYTHONSTARTUP is fine
- with os_helper.temp_dir() as tmpdir:
- script = os.path.join(tmpdir, "pythonstartup.py")
- with open(script, "w") as f:
- f.write("print('from pythonstartup')" + os.linesep)
-
- env = os.environ.copy()
- env['PYTHONSTARTUP'] = script
- env["PYTHON_HISTORY"] = os.path.join(tmpdir, ".pythonhist")
- p = make_repl(env)
- p.stdin.write("1/0")
- output = kill_python(p)
- expected = dedent("""
- Traceback (most recent call last):
- File "<stdin>", line 1, in <module>
- 1/0
- ~^~
- ZeroDivisionError: division by zero
- """)
- self.assertIn("from pythonstartup", output)
- self.assertIn(expected, output)
-
- # case 2: error in PYTHONSTARTUP triggered by user input
- with os_helper.temp_dir() as tmpdir:
- script = os.path.join(tmpdir, "pythonstartup.py")
- with open(script, "w") as f:
- f.write("def foo():\n 1/0\n")
-
- env = os.environ.copy()
- env['PYTHONSTARTUP'] = script
- env["PYTHON_HISTORY"] = os.path.join(tmpdir, ".pythonhist")
- p = make_repl(env)
- p.stdin.write('foo()')
- output = kill_python(p)
- expected = dedent("""
- Traceback (most recent call last):
- File "<stdin>", line 1, in <module>
- foo()
- ~~~^^
- File "%s", line 2, in foo
- 1/0
- ~^~
- ZeroDivisionError: division by zero
- """) % script
- self.assertIn(expected, output)
-
-
-
  def test_runsource_show_syntax_error_location(self):
  user_input = dedent("""def f(x, x): ...
  """)
@@ -292,23 +244,46 @@ def bar(x):
  expected = "(30, None, [\'def foo(x):\\n\', \' return x + 1\\n\', \'\\n\'], \'<stdin>\')"
  self.assertIn(expected, output, expected)
 
- def test_asyncio_repl_reaches_python_startup_script(self):
- with os_helper.temp_dir() as tmpdir:
- script = os.path.join(tmpdir, "pythonstartup.py")
- with open(script, "w") as f:
- f.write("print('pythonstartup done!')" + os.linesep)
- f.write("exit(0)" + os.linesep)
-
- env = os.environ.copy()
- env["PYTHON_HISTORY"] = os.path.join(tmpdir, ".asyncio_history")
- env["PYTHONSTARTUP"] = script
- subprocess.check_call(
- [sys.executable, "-m", "asyncio"],
- stdout=subprocess.PIPE,
- stderr=subprocess.PIPE,
- env=env,
- timeout=SHORT_TIMEOUT,
- )
+ def test_pythonstartup_success(self):
+ # errors based on https://github.com/python/cpython/issues/137576
+ # case 1: error in user input, but PYTHONSTARTUP is fine
+ startup_code = "print('notice from pythonstartup')"
+ startup_env = self.enterContext(new_startup_env(code=startup_code))
+ # -q to suppress noise
+ p = spawn_repl("-q", env=os.environ | startup_env, isolated=False)
+ p.stdin.write("1/0")
+ output_lines = kill_python(p).splitlines()
+ self.assertEqual(output_lines[0], 'notice from pythonstartup')
+
+ traceback_lines = output_lines[2:-1]
+ expected_lines = [
+ 'Traceback (most recent call last):',
+ ' File "<stdin>", line 1, in <module>',
+ ' 1/0',
+ ' ~^~',
+ 'ZeroDivisionError: division by zero',
+ ]
+ self.assertEqual(traceback_lines, expected_lines)
+
+ def test_pythonstartup_failure(self):
+ # case 2: error in PYTHONSTARTUP triggered by user input
+ startup_code = "def foo():\n 1/0\n"
+ startup_env = self.enterContext(new_startup_env(code=startup_code))
+ # -q to suppress noise
+ p = spawn_repl("-q", env=os.environ | startup_env, isolated=False)
+ p.stdin.write("foo()")
+ traceback_lines = kill_python(p).splitlines()[1:-1]
+ expected_lines = [
+ 'Traceback (most recent call last):',
+ ' File "<stdin>", line 1, in <module>',
+ ' foo()',
+ ' ~~~^^',
+ f' File "{startup_env['PYTHONSTARTUP']}", line 2, in foo',
+ ' 1/0',
+ ' ~^~',
+ 'ZeroDivisionError: division by zero',
+ ]
+ self.assertEqual(traceback_lines, expected_lines)
 
  @unittest.skipUnless(pty, "requires pty")
  def test_asyncio_repl_is_ok(self):
@@ -365,6 +340,7 @@ def f():
  self.assertEqual(traceback_lines, expected_lines)
 
 
+@support.force_not_colorized_test_class
 class TestAsyncioREPL(unittest.TestCase):
  def test_multiple_statements_fail_early(self):
  user_input = "1 / 0; print(f'afterwards: {1+1}')"
@@ -409,6 +385,55 @@ def test_toplevel_contextvars_async(self):
  expected = "toplevel contextvar test: ok"
  self.assertIn(expected, output, expected)
 
+ def test_pythonstartup_success(self):
+ startup_code = "import sys\nprint('notice from pythonstartup in asyncio repl', file=sys.stderr)"
+ startup_env = self.enterContext(new_startup_env(code=startup_code, histfile=".asyncio_history"))
+ p = spawn_asyncio_repl(env=os.environ | startup_env, stderr=subprocess.PIPE, isolated=False)
+ p.stdin.write("1/0")
+ kill_python(p)
+ output_lines = p.stderr.read().splitlines()
+ p.stderr.close()
+
+ self.assertEqual(output_lines[3], 'notice from pythonstartup in asyncio repl')
+
+ tb_start_lines = output_lines[5:6]
+ tb_final_lines = output_lines[13:]
+ expected_lines = [
+ 'Traceback (most recent call last):',
+ ' File "<stdin>", line 1, in <module>',
+ ' 1/0',
+ ' ~^~',
+ 'ZeroDivisionError: division by zero',
+ '',
+ 'exiting asyncio REPL...',
+ ]
+ self.assertEqual(tb_start_lines + tb_final_lines, expected_lines)
+
+ def test_pythonstartup_failure(self):
+ startup_code = "def foo():\n 1/0\n"
+ startup_env = self.enterContext(new_startup_env(code=startup_code, histfile=".asyncio_history"))
+ p = spawn_asyncio_repl(env=os.environ | startup_env, stderr=subprocess.PIPE, isolated=False)
+ p.stdin.write("foo()")
+ kill_python(p)
+ output_lines = p.stderr.read().splitlines()
+ p.stderr.close()
+
+ tb_start_lines = output_lines[4:5]
+ tb_final_lines = output_lines[12:]
+ expected_lines = [
+ 'Traceback (most recent call last):',
+ ' File "<stdin>", line 1, in <module>',
+ ' foo()',
+ ' ~~~^^',
+ f' File "{startup_env['PYTHONSTARTUP']}", line 2, in foo',
+ ' 1/0',
+ ' ~^~',
+ 'ZeroDivisionError: division by zero',
+ '',
+ 'exiting asyncio REPL...',
+ ]
+ self.assertEqual(tb_start_lines + tb_final_lines, expected_lines)
+
 
 if __name__ == "__main__":
  unittest.main()

Misc/NEWS.d/next/Library/2025-10-18-12-13-39.gh-issue-140287.49iU-4.rst

@@ -0,0 +1,2 @@
+The asyncio REPL now properly handles exceptions in ``PYTHONSTARTUP``
+scripts. Patch by Bartosz Sławecki in :gh:`140287`.