1 files changed, 44 insertions, 0 deletions
diff --git a/src/prompt_toolkit/clipboard/in_memory.py b/src/prompt_toolkit/clipboard/in_memory.py
new file mode 100644
index 0000000..d9ae081
--- /dev/null
+++ b/src/prompt_toolkit/clipboard/in_memory.py
@@ -0,0 +1,44 @@
+from __future__ import annotations
+
+from collections import deque
+
+from .base import Clipboard, ClipboardData
+
+__all__ = [
+    "InMemoryClipboard",
+]
+
+
+class InMemoryClipboard(Clipboard):
+    """
+    Default clipboard implementation.
+    Just keep the data in memory.
+
+    This implements a kill-ring, for Emacs mode.
+    """
+
+    def __init__(self, data: ClipboardData | None = None, max_size: int = 60) -> None:
+        assert max_size >= 1
+
+        self.max_size = max_size
+        self._ring: deque[ClipboardData] = deque()
+
+        if data is not None:
+            self.set_data(data)
+
+    def set_data(self, data: ClipboardData) -> None:
+        self._ring.appendleft(data)
+
+        while len(self._ring) > self.max_size:
+            self._ring.pop()
+
+    def get_data(self) -> ClipboardData:
+        if self._ring:
+            return self._ring[0]
+        else:
+            return ClipboardData()
+
+    def rotate(self) -> None:
+        if self._ring:
+            # Add the very first item at the end.
+            self._ring.append(self._ring.popleft())