diff --git a/go.mod b/go.mod
index ae5afb2..91c06fa 100644
--- a/go.mod
+++ b/go.mod
@@ -4,5 +4,6 @@ go 1.16
 
 require (
 	github.com/cactus/tai64 v1.0.2
-	gotest.tools/v3 v3.5.0
+	github.com/google/go-cmp v0.6.0 // indirect
+	gotest.tools/v3 v3.5.1
 )
diff --git a/go.sum b/go.sum
index a6cbd59..4d9abdb 100644
--- a/go.sum
+++ b/go.sum
@@ -1,7 +1,8 @@
 github.com/cactus/tai64 v1.0.2 h1:c5rm3aQ9z3b6Vva2LXRSICx/Rpu9rj4MHEzRG1g7dK0=
 github.com/cactus/tai64 v1.0.2/go.mod h1:gu5LAXd6eWwrRD/HPw+aTrJF5WkieYswRVLSNslKGg4=
-github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
 github.com/google/go-cmp v0.5.9/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
+github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
+github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
@@ -32,5 +33,5 @@ golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtn
 golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=
 golang.org/x/tools v0.2.0/go.mod h1:y4OqIKeOV/fWJetJ8bXPU1sEVniLMIyDAZWeHdV+NTA=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-gotest.tools/v3 v3.5.0 h1:Ljk6PdHdOhAb5aDMWXjDLMMhph+BpztA4v1QdqEW2eY=
-gotest.tools/v3 v3.5.0/go.mod h1:isy3WKz7GK6uNw/sbHzfKBLvlvXwUyV06n6brMxxopU=
+gotest.tools/v3 v3.5.1 h1:EENdUnS3pdur5nybKYIh2Vfgc8IUNBjxDPSjtiJcOzU=
+gotest.tools/v3 v3.5.1/go.mod h1:isy3WKz7GK6uNw/sbHzfKBLvlvXwUyV06n6brMxxopU=