# HG changeset patch
# User Gregory Szorc <gregory.szorc@gmail.com>
# Date 1499142399 25200
# Node ID f48422ab81aa967fc99f90e658a4539cc3eff930
# Parent  b93df142485e8431746abac1f0ed5c20c0eaf0c4
show: document why accidentally quadratic is (probably) acceptable

diff -r b93df142485e -r f48422ab81aa hgext/show.py
--- a/hgext/show.py	Mon Jul 03 21:18:32 2017 -0700
+++ b/hgext/show.py	Mon Jul 03 21:26:39 2017 -0700
@@ -215,6 +215,11 @@
 
         stackrevs.add(ctx.rev())
 
+        # ctx.children() within a function iterating on descandants
+        # potentially has severe performance concerns because revlog.children()
+        # iterates over all revisions after ctx's node. However, the number of
+        # draft changesets should be a reasonably small number. So even if
+        # this is quadratic, the perf impact should be minimal.
         if len(ctx.children()) > 1:
             branchpointattip = True
             break