added os_test.go and removed wmi for testing

Signed-off-by: Ben Ridley <benridley29@gmail.com>

collector/os_test.go

@@ -0,0 +1,23 @@
+package collector
+
+import (
+	"testing"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+func BenchmarkOsCollect(b *testing.B) {
+	o, err := NewOSCollector()
+	if err != nil {
+		b.Error(err)
+	}
+	metrics := make(chan prometheus.Metric)
+	go func() {
+		for {
+			<-metrics
+		}
+	}()
+	for i := 0; i < b.N; i++ {
+		o.Collect(&ScrapeContext{}, metrics)
+	}
+}