gh-121790: Fix interactive console initialization

Lib/_pyrepl/main.py

@@ -23,7 +23,7 @@
 
 def interactive_console(mainmodule=None, quiet=False, pythonstartup=False):
     if not CAN_USE_PYREPL:
-        if not os.environ.get('PYTHON_BASIC_REPL', None) and FAIL_REASON:
+        if not os.getenv('PYTHON_BASIC_REPL') and FAIL_REASON:
             from .trace import trace
             trace(FAIL_REASON)
             print(FAIL_REASON, file=sys.stderr)
@@ -51,5 +51,8 @@ def interactive_console(mainmodule=None, quiet=False, pythonstartup=False):
     if not hasattr(sys, "ps2"):
         sys.ps2 = "... "
 
+    from .console import InteractiveColoredConsole
     from .simple_interact import run_multiline_interactive_console
-    run_multiline_interactive_console(namespace)
+    console = InteractiveColoredConsole(namespace, filename="<stdin>")
+    run_multiline_interactive_console(console)
+

Lib/_pyrepl/readline.py

@@ -58,7 +58,7 @@
 TYPE_CHECKING = False
 
 if TYPE_CHECKING:
-    from typing import Any
+    from typing import Any, Mapping
 
 
 MoreLinesCallable = Callable[[str], bool]
@@ -559,7 +559,7 @@ def stub(*args: object, **kwds: object) -> None:
 # ____________________________________________________________
 
 
-def _setup(namespace: dict[str, Any]) -> None:
+def _setup(namespace: Mapping[str, Any]) -> None:
     global raw_input
     if raw_input is not None:
         return  # don't run _setup twice

Lib/_pyrepl/simple_interact.py

@@ -27,12 +27,9 @@
 
 import _sitebuiltins
 import linecache
-import builtins
 import sys
 import code
-from types import ModuleType
 
-from .console import InteractiveColoredConsole
 from .readline import _get_reader, multiline_input
 
 TYPE_CHECKING = False
@@ -82,17 +79,12 @@ def _clear_screen():
 
 
 def run_multiline_interactive_console(
-    namespace: dict[str, Any],
+    console: code.InteractiveConsole,
+    *,
     future_flags: int = 0,
-    console: code.InteractiveConsole | None = None,
 ) -> None:
     from .readline import _setup
-    _setup(namespace)
-
-    if console is None:
-        console = InteractiveColoredConsole(
-            namespace, filename="<stdin>"
-        )
+    _setup(console.locals)
     if future_flags:
         console.compile.compiler.flags |= future_flags
 

Lib/asyncio/__main__.py

@@ -97,30 +97,16 @@ def run(self):
                     exec(startup_code, console.locals)
 
             ps1 = getattr(sys, "ps1", ">>> ")
-            if can_colorize():
+            if can_colorize() and CAN_USE_PYREPL:
                 ps1 = f"{ANSIColors.BOLD_MAGENTA}{ps1}{ANSIColors.RESET}"
             console.write(f"{ps1}import asyncio\n")
 
-            try:
-                import errno
-                if os.getenv("PYTHON_BASIC_REPL"):
-                    raise RuntimeError("user environment requested basic REPL")
-                if not os.isatty(sys.stdin.fileno()):
-                    return_code = errno.ENOTTY
-                    raise OSError(return_code, "tty required", "stdin")
-
-                # This import will fail on operating systems with no termios.
+            if CAN_USE_PYREPL:
                 from _pyrepl.simple_interact import (
-                    check,
                     run_multiline_interactive_console,
                 )
-                if err := check():
-                    raise RuntimeError(err)
-            except Exception as e:
-                console.interact(banner="", exitmsg="")
-            else:
                 try:
-                    run_multiline_interactive_console(console=console)
+                    run_multiline_interactive_console(console)
                 except SystemExit:
                     # expected via the `exit` and `quit` commands
                     pass
@@ -129,6 +115,8 @@ def run(self):
                     console.showtraceback()
                     console.write("Internal error, ")
                     return_code = 1
+            else:
+                console.interact(banner="", exitmsg="")
         finally:
             warnings.filterwarnings(
                 'ignore',
@@ -139,7 +127,10 @@ def run(self):
 
 
 if __name__ == '__main__':
-    CAN_USE_PYREPL = True
+    if os.getenv('PYTHON_BASIC_REPL'):
+        CAN_USE_PYREPL = False
+    else:
+        from _pyrepl.main import CAN_USE_PYREPL
 
     return_code = 0
     loop = asyncio.new_event_loop()

Lib/site.py

@@ -517,10 +517,7 @@ def register_readline():
         pass
 
     if readline.get_current_history_length() == 0:
-        try:
-            from _pyrepl.main import CAN_USE_PYREPL
-        except ImportError:
-            CAN_USE_PYREPL = False
+        from _pyrepl.main import CAN_USE_PYREPL
         # If no history was loaded, default to .python_history,
         # or PYTHON_HISTORY.
         # The guard is necessary to avoid doubling history size at

Lib/test/test_repl.py

@@ -1,15 +1,29 @@
 """Test the interactive interpreter."""
 
+from io import BytesIO
 import os
+from re import sub
+import tempfile
+import select
 import subprocess
 import sys
 import unittest
 from textwrap import dedent
 from test import support
-from test.support import cpython_only, has_subprocess_support, SuppressCrashReport
+from test.support import (
+    cpython_only,
+    has_subprocess_support,
+    SuppressCrashReport,
+    SHORT_TIMEOUT,
+)
 from test.support.script_helper import assert_python_failure, kill_python, assert_python_ok
 from test.support.import_helper import import_module
 
+try:
+    import pty
+except ImportError:
+    pty = None
+
 
 if not has_subprocess_support:
     raise unittest.SkipTest("test module requires subprocess")
@@ -195,9 +209,52 @@ 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_no_tty_fails(self):
-        assert assert_python_failure("-m", "asyncio")
+    def test_asyncio_repl_reaches_python_startup_script(self):
+        with tempfile.TemporaryDirectory() as tmpdir:
+            script = os.path.join(tmpdir, "script.py")
+            with open(script, "w") as f:
+                f.write("exit(0)")
+
+            subprocess.check_call(
+                [sys.executable, "-m", "asyncio"],
+                stdout=subprocess.PIPE,
+                stderr=subprocess.PIPE,
+                env={"PYTHONSTARTUP": script}
+            )
+
+    @unittest.skipUnless(pty, "requires pty")
+    def test_asyncio_repl_is_ok(self):
+        m, s = pty.openpty()
+        cmd = [sys.executable, "-m", "asyncio"]
+        proc = subprocess.Popen(
+            cmd,
+            stdin=s,
+            stdout=s,
+            stderr=s,
+            text=True,
+            close_fds=True,
+            env=os.environ,
+        )
+        os.close(s)
+        os.write(m, b"await asyncio.sleep(0)\n")
+        os.write(m, b"exit()\n")
+        output = []
+        while select.select([m], [], [], SHORT_TIMEOUT)[0]:
+            try:
+                data = os.read(m, 1024).decode("utf-8")
+                if not data:
+                    break
+            except OSError:
+                break
+            output.append(data)
+        os.close(m)
+        try:
+            exit_code = proc.wait(timeout=SHORT_TIMEOUT)
+        except subprocess.TimeoutExpired:
+            proc.kill()
+            exit_code = proc.wait()
 
+        self.assertEqual(exit_code, 0)
 
 class TestInteractiveModeSyntaxErrors(unittest.TestCase):