diff --git a/gitindex/tree_test.go b/gitindex/tree_test.go
index 74316f5..9314aba 100644
--- a/gitindex/tree_test.go
+++ b/gitindex/tree_test.go
@@ -44,6 +44,8 @@
 echo acont > afile
 echo sub-cont > subdir/sub-file
 git add afile subdir/sub-file
+git config user.email "you@example.com"
+git config user.name "Your Name"
 git commit -am amsg
 
 cd ..
@@ -51,6 +53,8 @@
 git init
 echo bcont > bfile
 git add bfile
+git config user.email "you@example.com"
+git config user.name "Your Name"
 git commit -am bmsg
 
 cd ../adir
@@ -301,6 +305,8 @@
 echo acont > afile
 echo sub-cont > subdir/sub-file
 git add afile subdir/sub-file
+git config user.email "you@example.com"
+git config user.name "Your Name"
 git commit -am amsg
 
 git branch branchdir/a