diff --git a/src/pkg/egress/stats/prom_registry_test.go b/src/pkg/egress/stats/prom_registry_test.go
index a8d63e47..fd8a07ad 100644
--- a/src/pkg/egress/stats/prom_registry_test.go
+++ b/src/pkg/egress/stats/prom_registry_test.go
@@ -20,35 +20,64 @@ var _ = Describe("Prometheus Registry", func() {
 
 	It("registers the gauge when it's first gotten", func() {
 		gauge := toPromGauge(registry.Get("metric_name", "origin", "unit", nil))
-		Expect(gauge.Desc().String()).To(Equal(`Desc{fqName: "metric_name", help: "vm metric", constLabels: {unit="unit"}, variableLabels: {}}`))
+		expectGauge(gauge, "metric_name", map[string]string{"unit": "unit"})
 
 		var registered prometheus.Gauge
 		Eventually(registerer.gauges).Should(Receive(&registered))
 
-		Expect(registered.Desc().String()).To(Equal(`Desc{fqName: "metric_name", help: "vm metric", constLabels: {unit="unit"}, variableLabels: {}}`))
+		expectGauge(registered, "metric_name", map[string]string{"unit": "unit"})
 	})
 
 	It("doesn't reregister gauges", func() {
 		gauge := toPromGauge(registry.Get("metric_name", "origin", "unit", nil))
-		Expect(gauge.Desc().String()).To(Equal(`Desc{fqName: "metric_name", help: "vm metric", constLabels: {unit="unit"}, variableLabels: {}}`))
+		expectGauge(gauge, "metric_name", map[string]string{"unit": "unit"})
 
 		gauge = toPromGauge(registry.Get("metric_name", "origin", "unit", nil))
-		Expect(gauge.Desc().String()).To(Equal(`Desc{fqName: "metric_name", help: "vm metric", constLabels: {unit="unit"}, variableLabels: {}}`))
+		expectGauge(gauge, "metric_name", map[string]string{"unit": "unit"})
 
 		Expect(registerer.gauges).To(HaveLen(1))
 	})
 
 	It("gauges with different tags are different gauges", func() {
 		gauge := toPromGauge(registry.Get("metric_name", "origin", "unit", map[string]string{"foo": "bar2"}))
-		Expect(gauge.Desc().String()).To(Equal(`Desc{fqName: "metric_name", help: "vm metric", constLabels: {foo="bar2",unit="unit"}, variableLabels: {}}`))
+		expectGauge(gauge, "metric_name", map[string]string{"foo": "bar2", "unit": "unit"})
 
 		gauge = toPromGauge(registry.Get("metric_name", "origin", "unit", map[string]string{"foo": "bar"}))
-		Expect(gauge.Desc().String()).To(Equal(`Desc{fqName: "metric_name", help: "vm metric", constLabels: {foo="bar",unit="unit"}, variableLabels: {}}`))
+		expectGauge(gauge, "metric_name", map[string]string{"foo": "bar", "unit": "unit"})
 
 		Expect(registerer.gauges).To(HaveLen(2))
 	})
 })
 
+// gaugeDesc is a plain, comparable projection of a collected gauge's public
+// contract (its exported name and const labels).
+type gaugeDesc struct {
+	Name   string
+	Labels map[string]string
+}
+
+// expectGauge collects the gauge through a real registry and compares its
+// public contract against the expected name and const labels as a single object.
+func expectGauge(g prometheus.Gauge, name string, constLabels map[string]string) {
+	GinkgoHelper()
+
+	reg := prometheus.NewRegistry()
+	Expect(reg.Register(g)).To(Succeed())
+
+	families, err := reg.Gather()
+	Expect(err).NotTo(HaveOccurred())
+	Expect(families).To(HaveLen(1))
+	Expect(families[0].GetMetric()).To(HaveLen(1))
+
+	labels := map[string]string{}
+	for _, p := range families[0].GetMetric()[0].GetLabel() {
+		labels[p.GetName()] = p.GetValue()
+	}
+
+	actual := gaugeDesc{Name: families[0].GetName(), Labels: labels}
+	Expect(actual).To(Equal(gaugeDesc{Name: name, Labels: constLabels}))
+}
+
 func toPromGauge(g stats.Gauge) prometheus.Gauge {
 	gauge, ok := g.(prometheus.Gauge)
 	Expect(ok).To(BeTrue())