intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 92 insertions, 0 deletions

diff --git a/contrib/python/prompt-toolkit/py2/prompt_toolkit/buffer_mapping.py b/contrib/python/prompt-toolkit/py2/prompt_toolkit/buffer_mapping.py
new file mode 100644
index 0000000000..34f443bd47
--- /dev/null
+++ b/contrib/python/prompt-toolkit/py2/prompt_toolkit/buffer_mapping.py
@@ -0,0 +1,92 @@
+"""
+The BufferMapping contains all the buffers for a command line interface, and it
+keeps track of which buffer gets the focus.
+"""
+from __future__ import unicode_literals
+from .enums import DEFAULT_BUFFER, SEARCH_BUFFER, SYSTEM_BUFFER, DUMMY_BUFFER
+from .buffer import Buffer, AcceptAction
+from .history import InMemoryHistory
+
+import six
+
+__all__ = (
+    'BufferMapping',
+)
+
+
+class BufferMapping(dict):
+    """
+    Dictionary that maps the name of the buffers to the
+    :class:`~prompt_toolkit.buffer.Buffer` instances.
+
+    This mapping also keeps track of which buffer currently has the focus.
+    (Some methods receive a 'cli' parameter. This is useful for applications
+    where this `BufferMapping` is shared between several applications.)
+    """
+    def __init__(self, buffers=None, initial=DEFAULT_BUFFER):
+        assert buffers is None or isinstance(buffers, dict)
+
+        # Start with an empty dict.
+        super(BufferMapping, self).__init__()
+
+        # Add default buffers.
+        self.update({
+            # For the 'search' and 'system' buffers, 'returnable' is False, in
+            # order to block normal Enter/ControlC behaviour.
+            DEFAULT_BUFFER: Buffer(accept_action=AcceptAction.RETURN_DOCUMENT),
+            SEARCH_BUFFER: Buffer(history=InMemoryHistory(), accept_action=AcceptAction.IGNORE),
+            SYSTEM_BUFFER: Buffer(history=InMemoryHistory(), accept_action=AcceptAction.IGNORE),
+            DUMMY_BUFFER: Buffer(read_only=True),
+        })
+
+        # Add received buffers.
+        if buffers is not None:
+            self.update(buffers)
+
+        # Focus stack.
+        self.focus_stack = [initial or DEFAULT_BUFFER]
+
+    def current(self, cli):
+        """
+        The active :class:`.Buffer`.
+        """
+        return self[self.focus_stack[-1]]
+
+    def current_name(self, cli):
+        """
+        The name of the active :class:`.Buffer`.
+        """
+        return self.focus_stack[-1]
+
+    def previous(self, cli):
+        """
+        Return the previously focussed :class:`.Buffer` or `None`.
+        """
+        if len(self.focus_stack) > 1:
+            try:
+                return self[self.focus_stack[-2]]
+            except KeyError:
+                pass
+
+    def focus(self, cli, buffer_name):
+        """
+        Focus the buffer with the given name.
+        """
+        assert isinstance(buffer_name, six.text_type)
+        self.focus_stack = [buffer_name]
+
+    def push_focus(self, cli, buffer_name):
+        """
+        Push buffer on the focus stack.
+        """
+        assert isinstance(buffer_name, six.text_type)
+        self.focus_stack.append(buffer_name)
+
+    def pop_focus(self, cli):
+        """
+        Pop buffer from the focus stack.
+        """
+        if len(self.focus_stack) > 1:
+            self.focus_stack.pop()
+        else:
+            raise IndexError('Cannot pop last item from the focus stack.')