From 85cdd281f1c92e7ecfb6484602bfec2518c3e877 Mon Sep 17 00:00:00 2001
From: Itamar Turner-Trauring <itamar@itamarst.org>
Date: Fri, 12 Feb 2021 09:47:48 -0500
Subject: [PATCH] Document trinary logic.

---
 src/allmydata/dirnode.py | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/allmydata/dirnode.py b/src/allmydata/dirnode.py
index 1fa170807..ea8e84e05 100644
--- a/src/allmydata/dirnode.py
+++ b/src/allmydata/dirnode.py
@@ -182,6 +182,11 @@ class MetadataSetter(object):
 
 class Adder(object):
     def __init__(self, node, entries=None, overwrite=True, create_readonly_node=None):
+        """
+        :param overwrite: Either True (allow overwriting anything existing),
+            False (don't allow overwriting), or ONLY_FILES (only files can be
+            overwritten).
+        """
         self.node = node
         if entries is None:
             entries = {}