From 9171b9e0adc40b209510189567d2b71b9f923977 Mon Sep 17 00:00:00 2001
From: "Mr. Outis" <mroutis@protonmail.com>
Date: Mon, 27 Jan 2020 12:07:28 -0600
Subject: [PATCH] :nail_care: add reference explaining git revisions

---
 tests/func/test_diff.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tests/func/test_diff.py b/tests/func/test_diff.py
index 39014540c9..d9f918fc15 100644
--- a/tests/func/test_diff.py
+++ b/tests/func/test_diff.py
@@ -156,6 +156,10 @@ def test_directories(tmp_dir, scm, dvc):
     scm.add("dir.dvc")
     scm.commit("delete a file")
 
+
+    # The ":/<text>" format is a way to specify revisions by commit message:
+    #       https://git-scm.com/docs/git-rev-parse
+    #
     assert dvc.diff(":/init", ":/directory") == {
         "added": [
             {