until stable: pin-dependency, update-vendor, update-bazel, lint-dep

vendor/github.com/xlab/treeprint/struct.go

@@ -0,0 +1,322 @@
+package treeprint
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+)
+
+type StructTreeOption int
+
+const (
+	StructNameTree StructTreeOption = iota
+	StructValueTree
+	StructTagTree
+	StructTypeTree
+	StructTypeSizeTree
+)
+
+func FromStruct(v interface{}, opt ...StructTreeOption) (Tree, error) {
+	var treeOpt StructTreeOption
+	if len(opt) > 0 {
+		treeOpt = opt[0]
+	}
+	switch treeOpt {
+	case StructNameTree:
+		tree := New()
+		err := nameTree(tree, v)
+		return tree, err
+	case StructValueTree:
+		tree := New()
+		err := valueTree(tree, v)
+		return tree, err
+	case StructTagTree:
+		tree := New()
+		err := tagTree(tree, v)
+		return tree, err
+	case StructTypeTree:
+		tree := New()
+		err := typeTree(tree, v)
+		return tree, err
+	case StructTypeSizeTree:
+		tree := New()
+		err := typeSizeTree(tree, v)
+		return tree, err
+	default:
+		err := fmt.Errorf("treeprint: invalid StructTreeOption %v", treeOpt)
+		return nil, err
+	}
+}
+
+type FmtFunc func(name string, v interface{}) (string, bool)
+
+func FromStructWithMeta(v interface{}, fmtFunc FmtFunc) (Tree, error) {
+	if fmtFunc == nil {
+		tree := New()
+		err := nameTree(tree, v)
+		return tree, err
+	}
+	tree := New()
+	err := metaTree(tree, v, fmtFunc)
+	return tree, err
+}
+
+func Repr(v interface{}) string {
+	tree := New()
+	vType := reflect.TypeOf(v)
+	vValue := reflect.ValueOf(v)
+	_, val, isStruct := getValue(vType, &vValue)
+	if !isStruct {
+		return fmt.Sprintf("%+v", val.Interface())
+	}
+	err := valueTree(tree, val.Interface())
+	if err != nil {
+		return err.Error()
+	}
+	return tree.String()
+}
+
+func nameTree(tree Tree, v interface{}) error {
+	typ, val, err := checkType(v)
+	if err != nil {
+		return err
+	}
+	fields := typ.NumField()
+	for i := 0; i < fields; i++ {
+		field := typ.Field(i)
+		fieldValue := val.Field(i)
+		name, skip, omit := getMeta(field.Name, field.Tag)
+		if skip || omit && isEmpty(&fieldValue) {
+			continue
+		}
+		typ, val, isStruct := getValue(field.Type, &fieldValue)
+		if !isStruct {
+			tree.AddNode(name)
+			continue
+		} else if subNum := typ.NumField(); subNum == 0 {
+			tree.AddNode(name)
+			continue
+		}
+		branch := tree.AddBranch(name)
+		if err := nameTree(branch, val.Interface()); err != nil {
+			err := fmt.Errorf("%v on struct branch %s", err, name)
+			return err
+		}
+	}
+	return nil
+}
+
+func getMeta(fieldName string, tag reflect.StructTag) (name string, skip, omit bool) {
+	if tagStr := tag.Get("tree"); len(tagStr) > 0 {
+		name, omit = tagSpec(tagStr)
+	}
+	if name == "-" {
+		return fieldName, true, omit
+	}
+	if len(name) == 0 {
+		name = fieldName
+	} else if trimmed := strings.TrimSpace(name); len(trimmed) == 0 {
+		name = fieldName
+	}
+	return
+}
+
+func valueTree(tree Tree, v interface{}) error {
+	typ, val, err := checkType(v)
+	if err != nil {
+		return err
+	}
+	fields := typ.NumField()
+	for i := 0; i < fields; i++ {
+		field := typ.Field(i)
+		fieldValue := val.Field(i)
+		name, skip, omit := getMeta(field.Name, field.Tag)
+		if skip || omit && isEmpty(&fieldValue) {
+			continue
+		}
+		typ, val, isStruct := getValue(field.Type, &fieldValue)
+		if !isStruct {
+			tree.AddMetaNode(val.Interface(), name)
+			continue
+		} else if subNum := typ.NumField(); subNum == 0 {
+			tree.AddMetaNode(val.Interface(), name)
+			continue
+		}
+		branch := tree.AddBranch(name)
+		if err := valueTree(branch, val.Interface()); err != nil {
+			err := fmt.Errorf("%v on struct branch %s", err, name)
+			return err
+		}
+	}
+	return nil
+}
+
+func tagTree(tree Tree, v interface{}) error {
+	typ, val, err := checkType(v)
+	if err != nil {
+		return err
+	}
+	fields := typ.NumField()
+	for i := 0; i < fields; i++ {
+		field := typ.Field(i)
+		fieldValue := val.Field(i)
+		name, skip, omit := getMeta(field.Name, field.Tag)
+		if skip || omit && isEmpty(&fieldValue) {
+			continue
+		}
+		filteredTag := filterTags(field.Tag)
+		typ, val, isStruct := getValue(field.Type, &fieldValue)
+		if !isStruct {
+			tree.AddMetaNode(filteredTag, name)
+			continue
+		} else if subNum := typ.NumField(); subNum == 0 {
+			tree.AddMetaNode(filteredTag, name)
+			continue
+		}
+		branch := tree.AddMetaBranch(filteredTag, name)
+		if err := tagTree(branch, val.Interface()); err != nil {
+			err := fmt.Errorf("%v on struct branch %s", err, name)
+			return err
+		}
+	}
+	return nil
+}
+
+func typeTree(tree Tree, v interface{}) error {
+	typ, val, err := checkType(v)
+	if err != nil {
+		return err
+	}
+	fields := typ.NumField()
+	for i := 0; i < fields; i++ {
+		field := typ.Field(i)
+		fieldValue := val.Field(i)
+		name, skip, omit := getMeta(field.Name, field.Tag)
+		if skip || omit && isEmpty(&fieldValue) {
+			continue
+		}
+		typ, val, isStruct := getValue(field.Type, &fieldValue)
+		typename := fmt.Sprintf("%T", val.Interface())
+		if !isStruct {
+			tree.AddMetaNode(typename, name)
+			continue
+		} else if subNum := typ.NumField(); subNum == 0 {
+			tree.AddMetaNode(typename, name)
+			continue
+		}
+		branch := tree.AddMetaBranch(typename, name)
+		if err := typeTree(branch, val.Interface()); err != nil {
+			err := fmt.Errorf("%v on struct branch %s", err, name)
+			return err
+		}
+	}
+	return nil
+}
+
+func typeSizeTree(tree Tree, v interface{}) error {
+	typ, val, err := checkType(v)
+	if err != nil {
+		return err
+	}
+	fields := typ.NumField()
+	for i := 0; i < fields; i++ {
+		field := typ.Field(i)
+		fieldValue := val.Field(i)
+		name, skip, omit := getMeta(field.Name, field.Tag)
+		if skip || omit && isEmpty(&fieldValue) {
+			continue
+		}
+		typ, val, isStruct := getValue(field.Type, &fieldValue)
+		typesize := typ.Size()
+		if !isStruct {
+			tree.AddMetaNode(typesize, name)
+			continue
+		} else if subNum := typ.NumField(); subNum == 0 {
+			tree.AddMetaNode(typesize, name)
+			continue
+		}
+		branch := tree.AddMetaBranch(typesize, name)
+		if err := typeSizeTree(branch, val.Interface()); err != nil {
+			err := fmt.Errorf("%v on struct branch %s", err, name)
+			return err
+		}
+	}
+	return nil
+}
+
+func metaTree(tree Tree, v interface{}, fmtFunc FmtFunc) error {
+	typ, val, err := checkType(v)
+	if err != nil {
+		return err
+	}
+	fields := typ.NumField()
+	for i := 0; i < fields; i++ {
+		field := typ.Field(i)
+		fieldValue := val.Field(i)
+		name, skip, omit := getMeta(field.Name, field.Tag)
+		if skip || omit && isEmpty(&fieldValue) {
+			continue
+		}
+		typ, val, isStruct := getValue(field.Type, &fieldValue)
+		formatted, show := fmtFunc(name, val.Interface())
+		if !isStruct {
+			if show {
+				tree.AddMetaNode(formatted, name)
+				continue
+			}
+			tree.AddNode(name)
+			continue
+		} else if subNum := typ.NumField(); subNum == 0 {
+			if show {
+				tree.AddMetaNode(formatted, name)
+				continue
+			}
+			tree.AddNode(name)
+			continue
+		}
+		var branch Tree
+		if show {
+			branch = tree.AddMetaBranch(formatted, name)
+		} else {
+			branch = tree.AddBranch(name)
+		}
+		if err := metaTree(branch, val.Interface(), fmtFunc); err != nil {
+			err := fmt.Errorf("%v on struct branch %s", err, name)
+			return err
+		}
+	}
+	return nil
+}
+
+func getValue(typ reflect.Type, val *reflect.Value) (reflect.Type, *reflect.Value, bool) {
+	switch typ.Kind() {
+	case reflect.Ptr:
+		typ = typ.Elem()
+		if typ.Kind() == reflect.Struct {
+			elem := val.Elem()
+			return typ, &elem, true
+		}
+	case reflect.Struct:
+		return typ, val, true
+	}
+	return typ, val, false
+}
+
+func checkType(v interface{}) (reflect.Type, *reflect.Value, error) {
+	typ := reflect.TypeOf(v)
+	val := reflect.ValueOf(v)
+	switch typ.Kind() {
+	case reflect.Ptr:
+		typ = typ.Elem()
+		if typ.Kind() != reflect.Struct {
+			err := fmt.Errorf("treeprint: %T is not a struct we could work with", v)
+			return nil, nil, err
+		}
+		val = val.Elem()
+	case reflect.Struct:
+	default:
+		err := fmt.Errorf("treeprint: %T is not a struct we could work with", v)
+		return nil, nil, err
+	}
+	return typ, &val, nil
+}