gh-111201: A new Python REPL (GH-111567)

Co-authored-by: Łukasz Langa <lukasz@langa.pl>
Co-authored-by: Marta Gómez Macías <mgmacias@google.com>
Co-authored-by: Lysandros Nikolaou <lisandrosnik@gmail.com>
Co-authored-by: Hugo van Kemenade <1324225+hugovk@users.noreply.github.com>
Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>

1 files changed, 112 insertions, 0 deletions

diff --git a/Lib/_pyrepl/console.py b/Lib/_pyrepl/console.py
new file mode 100644
index 0000000..d7e86e7
--- /dev/null
+++ b/Lib/_pyrepl/console.py
@@ -0,0 +1,112 @@
+#   Copyright 2000-2004 Michael Hudson-Doyle <micahel@gmail.com>
+#
+#                        All Rights Reserved
+#
+#
+# Permission to use, copy, modify, and distribute this software and
+# its documentation for any purpose is hereby granted without fee,
+# provided that the above copyright notice appear in all copies and
+# that both that copyright notice and this permission notice appear in
+# supporting documentation.
+#
+# THE AUTHOR MICHAEL HUDSON DISCLAIMS ALL WARRANTIES WITH REGARD TO
+# THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+# AND FITNESS, IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL,
+# INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
+# RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF
+# CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+# CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+from __future__ import annotations
+
+from abc import ABC, abstractmethod
+from dataclasses import dataclass, field
+
+
+@dataclass
+class Event:
+    evt: str
+    data: str
+    raw: bytes = b""
+
+
+@dataclass
+class Console(ABC):
+    screen: list[str] = field(default_factory=list)
+    height: int = 25
+    width: int = 80
+
+    @abstractmethod
+    def refresh(self, screen: list[str], xy: tuple[int, int]) -> None: ...
+
+    @abstractmethod
+    def prepare(self) -> None: ...
+
+    @abstractmethod
+    def restore(self) -> None: ...
+
+    @abstractmethod
+    def move_cursor(self, x: int, y: int) -> None: ...
+
+    @abstractmethod
+    def set_cursor_vis(self, visible: bool) -> None: ...
+
+    @abstractmethod
+    def getheightwidth(self) -> tuple[int, int]:
+        """Return (height, width) where height and width are the height
+        and width of the terminal window in characters."""
+        ...
+
+    @abstractmethod
+    def get_event(self, block: bool = True) -> Event | None:
+        """Return an Event instance.  Returns None if |block| is false
+        and there is no event pending, otherwise waits for the
+        completion of an event."""
+        ...
+
+    @abstractmethod
+    def push_char(self, char: int | bytes) -> None:
+        """
+        Push a character to the console event queue.
+        """
+        ...
+
+    @abstractmethod
+    def beep(self) -> None: ...
+
+    @abstractmethod
+    def clear(self) -> None:
+        """Wipe the screen"""
+        ...
+
+    @abstractmethod
+    def finish(self) -> None:
+        """Move the cursor to the end of the display and otherwise get
+        ready for end.  XXX could be merged with restore?  Hmm."""
+        ...
+
+    @abstractmethod
+    def flushoutput(self) -> None:
+        """Flush all output to the screen (assuming there's some
+        buffering going on somewhere)."""
+        ...
+
+    @abstractmethod
+    def forgetinput(self) -> None:
+        """Forget all pending, but not yet processed input."""
+        ...
+
+    @abstractmethod
+    def getpending(self) -> Event:
+        """Return the characters that have been typed but not yet
+        processed."""
+        ...
+
+    @abstractmethod
+    def wait(self) -> None:
+        """Wait for an event."""
+        ...
+
+    @abstractmethod
+    def repaint(self) -> None:
+        ...