1 files changed, 91 insertions, 0 deletions
diff --git a/vendor/sigs.k8s.io/structured-merge-diff/v4/value/jsontagutil.go b/vendor/sigs.k8s.io/structured-merge-diff/v4/value/jsontagutil.go
new file mode 100644
index 000000000..d4adb8fc9
--- /dev/null
+++ b/vendor/sigs.k8s.io/structured-merge-diff/v4/value/jsontagutil.go
@@ -0,0 +1,91 @@
+/*
+Copyright 2019 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package value
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+)
+
+// TODO: This implements the same functionality as https://github.com/kubernetes/kubernetes/blob/master/staging/src/k8s.io/apimachinery/pkg/runtime/converter.go#L236
+// but is based on the highly efficient approach from https://golang.org/src/encoding/json/encode.go
+
+func lookupJsonTags(f reflect.StructField) (name string, omit bool, inline bool, omitempty bool) {
+	tag := f.Tag.Get("json")
+	if tag == "-" {
+		return "", true, false, false
+	}
+	name, opts := parseTag(tag)
+	if name == "" {
+		name = f.Name
+	}
+	return name, false, opts.Contains("inline"), opts.Contains("omitempty")
+}
+
+func isZero(v reflect.Value) bool {
+	switch v.Kind() {
+	case reflect.Array, reflect.Map, reflect.Slice, reflect.String:
+		return v.Len() == 0
+	case reflect.Bool:
+		return !v.Bool()
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return v.Int() == 0
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return v.Uint() == 0
+	case reflect.Float32, reflect.Float64:
+		return v.Float() == 0
+	case reflect.Interface, reflect.Ptr:
+		return v.IsNil()
+	case reflect.Chan, reflect.Func:
+		panic(fmt.Sprintf("unsupported type: %v", v.Type()))
+	}
+	return false
+}
+
+type tagOptions string
+
+// parseTag splits a struct field's json tag into its name and
+// comma-separated options.
+func parseTag(tag string) (string, tagOptions) {
+	if idx := strings.Index(tag, ","); idx != -1 {
+		return tag[:idx], tagOptions(tag[idx+1:])
+	}
+	return tag, tagOptions("")
+}
+
+// Contains reports whether a comma-separated list of options
+// contains a particular substr flag. substr must be surrounded by a
+// string boundary or commas.
+func (o tagOptions) Contains(optionName string) bool {
+	if len(o) == 0 {
+		return false
+	}
+	s := string(o)
+	for s != "" {
+		var next string
+		i := strings.Index(s, ",")
+		if i >= 0 {
+			s, next = s[:i], s[i+1:]
+		}
+		if s == optionName {
+			return true
+		}
+		s = next
+	}
+	return false
+}