gh-149392: Add "Open Input in Editor" support in PyREPL

Lib/_pyrepl/commands.py

@@ -24,6 +24,10 @@
 import time
 from typing import TYPE_CHECKING
 
+lazy import subprocess
+lazy import tempfile
+lazy from pathlib import Path
+
 # Categories of actions:
 #  killing
 #  yanking
@@ -519,3 +523,46 @@ def do(self) -> None:
             s=time.time() - start,
         )
         self.reader.insert(data.replace(done, ""))
+
+
+class open_input_in_editor(EditCommand):
+    def do(self) -> None:
+        r = self.reader
+
+        editor = os.environ.get("VISUAL") or os.environ.get("EDITOR")
+        if not editor:
+            editor = "vi" if os.name != "nt" else "notepad"
+
+        with tempfile.NamedTemporaryFile(
+            mode="w+", suffix=".py", delete=False, encoding="utf-8"
+        ) as f:
+            tmp_path = Path(f.name)
+            f.write("".join(r.buffer))
+            f.flush()
+
+        try:
+            with r.suspend():
+                cmd = editor.split() + [str(tmp_path)]
+                try:
+                    subprocess.call(cmd)
+                except FileNotFoundError:
+                    r.error(f"Editor not found: {editor}")
+                    return
+                except Exception as e:
+                    r.error(f"Failed to run editor: {e}")
+                    return
+
+            try:
+                new_text = tmp_path.read_text(encoding="utf-8").rstrip("\n")
+                r.buffer.clear()
+                r.buffer.extend(new_text)
+                r.pos = len(r.buffer)
+                r.invalidate_full()
+                r.console.repaint()
+            except Exception as e:
+                r.error(f"Failed to read edited file: {e}")
+        finally:
+            try:
+                tmp_path.unlink(missing_ok=True)
+            except Exception:
+                pass

Lib/_pyrepl/reader.py

@@ -104,6 +104,7 @@ def make_default_commands() -> dict[CommandName, CommandClass]:
         (r"\C-u", "unix-line-discard"),
         (r"\C-w", "unix-word-rubout"),
         (r"\C-x\C-u", "upcase-region"),
+        (r"\C-x\C-e", "open-input-in-editor"),
         (r"\C-y", "yank"),
         *(() if sys.platform == "win32" else ((r"\C-z", "suspend"), )),
         (r"\M-b", "backward-word"),

Misc/NEWS.d/next/Library/2026-05-05-10-12-13.gh-issue-149392.vsURNh.rst

@@ -0,0 +1 @@
+Add "Open Input in Editor" support to :mod:`!_pyrepl`.