databroker: fix fast forward (#4194)

databroker: fix fast forward (#4192)

* databroker: sort configs

* databroker: fix fast-forward

* newest not oldest

Co-authored-by: Caleb Doxsey <cdoxsey@pomerium.com>

pkg/slices/slices_test.go

@@ -0,0 +1,32 @@
+package slices
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestReverse(t *testing.T) {
+	t.Parallel()
+
+	for _, tc := range []struct {
+		in     []int
+		expect []int
+	}{
+		{in: []int{1, 2, 3}, expect: []int{3, 2, 1}},
+		{in: []int{1, 2}, expect: []int{2, 1}},
+		{in: []int{1}, expect: []int{1}},
+	} {
+		s := make([]int, len(tc.in))
+		copy(s, tc.in)
+		Reverse(s)
+		assert.Equal(t, tc.expect, s)
+	}
+}
+
+func TestUniqueBy(t *testing.T) {
+	t.Parallel()
+
+	s := UniqueBy([]int{1, 2, 3, 4, 3, 1, 1, 4, 2}, func(i int) int { return i % 3 })
+	assert.Equal(t, []int{1, 2, 3}, s)
+}