Measure delivery output and version costs

internal/runtimeinfo/performance_test.go

@@ -0,0 +1,31 @@
+package runtimeinfo
+
+import (
+	"runtime/debug"
+	"testing"
+)
+
+var performanceVersionSink string
+
+func BenchmarkPerformanceVersion(b *testing.B) {
+	b.Run("Injected", func(b *testing.B) {
+		b.ReportAllocs()
+		b.ResetTimer()
+		for i := 0; i < b.N; i++ {
+			performanceVersionSink = version("v1.2.3", debug.ReadBuildInfo)
+			if performanceVersionSink != "v1.2.3" {
+				b.Fatalf("version() = %q, want injected version", performanceVersionSink)
+			}
+		}
+	})
+	b.Run("RealMetadataFallback", func(b *testing.B) {
+		b.ReportAllocs()
+		b.ResetTimer()
+		for i := 0; i < b.N; i++ {
+			performanceVersionSink = Version()
+			if performanceVersionSink == "" {
+				b.Fatal("Version() returned an empty version")
+			}
+		}
+	})
+}