[chore]: Bump github.com/KimMachineGun/automemlimit from 0.4.0 to 0.5.0 (#2560)

vendor/github.com/KimMachineGun/automemlimit/memlimit/experiment.go

@@ -0,0 +1,59 @@
+package memlimit
+
+import (
+	"fmt"
+	"os"
+	"reflect"
+	"strings"
+)
+
+const (
+	envAUTOMEMLIMIT_EXPERIMENT = "AUTOMEMLIMIT_EXPERIMENT"
+)
+
+// Experiments is a set of experiment flags.
+// It is used to enable experimental features.
+//
+// You can set the flags by setting the environment variable AUTOMEMLIMIT_EXPERIMENT.
+// The value of the environment variable is a comma-separated list of experiment names.
+//
+// The following experiment names are known:
+//
+//   - none: disable all experiments
+//   - system: enable fallback to system memory limit
+type Experiments struct {
+	// System enables fallback to system memory limit.
+	System bool
+}
+
+func parseExperiments() (Experiments, error) {
+	var exp Experiments
+
+	// Create a map of known experiment names.
+	names := make(map[string]func(bool))
+	rv := reflect.ValueOf(&exp).Elem()
+	rt := rv.Type()
+	for i := 0; i < rt.NumField(); i++ {
+		field := rv.Field(i)
+		names[strings.ToLower(rt.Field(i).Name)] = field.SetBool
+	}
+
+	// Parse names.
+	for _, f := range strings.Split(os.Getenv(envAUTOMEMLIMIT_EXPERIMENT), ",") {
+		if f == "" {
+			continue
+		}
+		if f == "none" {
+			exp = Experiments{}
+			continue
+		}
+		val := true
+		set, ok := names[f]
+		if !ok {
+			return Experiments{}, fmt.Errorf("unknown AUTOMEMLIMIT_EXPERIMENT %s", f)
+		}
+		set(val)
+	}
+
+	return exp, nil
+}