See D18676#228215, and here:

https://secure.phabricator.com/rPbd3c23

There are two commits this matches, rPbd3c2355e8 and rPbd3c239d5a.

This is (probably) dying on executeOne(). Instead, it should execute, then give you options if more than one result comes back. The experience should be something like what git show offers, "That's ambiguous, pick which option you actually wanted."

$ git show bd3c23
error: short SHA1 bd3c23 is ambiguous
hint: The candidates are:
hint:   bd3c2355e8 commit 2011-12-20 - Match usernames in any case in commit message object lists (CC, Reviewers, etc.)
hint:   bd3c239d5a commit 2014-07-17 - Remove a stray `setActor()` on EdgeEditor