aboutsummaryrefslogtreecommitdiff
path: root/vendor/dario.cat/mergo/merge.go
diff options
context:
space:
mode:
Diffstat (limited to 'vendor/dario.cat/mergo/merge.go')
-rw-r--r--vendor/dario.cat/mergo/merge.go409
1 files changed, 409 insertions, 0 deletions
diff --git a/vendor/dario.cat/mergo/merge.go b/vendor/dario.cat/mergo/merge.go
new file mode 100644
index 0000000..0ef9b21
--- /dev/null
+++ b/vendor/dario.cat/mergo/merge.go
@@ -0,0 +1,409 @@
+// Copyright 2013 Dario Castañé. All rights reserved.
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Based on src/pkg/reflect/deepequal.go from official
+// golang's stdlib.
+
+package mergo
+
+import (
+ "fmt"
+ "reflect"
+)
+
+func hasMergeableFields(dst reflect.Value) (exported bool) {
+ for i, n := 0, dst.NumField(); i < n; i++ {
+ field := dst.Type().Field(i)
+ if field.Anonymous && dst.Field(i).Kind() == reflect.Struct {
+ exported = exported || hasMergeableFields(dst.Field(i))
+ } else if isExportedComponent(&field) {
+ exported = exported || len(field.PkgPath) == 0
+ }
+ }
+ return
+}
+
+func isExportedComponent(field *reflect.StructField) bool {
+ pkgPath := field.PkgPath
+ if len(pkgPath) > 0 {
+ return false
+ }
+ c := field.Name[0]
+ if 'a' <= c && c <= 'z' || c == '_' {
+ return false
+ }
+ return true
+}
+
+type Config struct {
+ Transformers Transformers
+ Overwrite bool
+ ShouldNotDereference bool
+ AppendSlice bool
+ TypeCheck bool
+ overwriteWithEmptyValue bool
+ overwriteSliceWithEmptyValue bool
+ sliceDeepCopy bool
+ debug bool
+}
+
+type Transformers interface {
+ Transformer(reflect.Type) func(dst, src reflect.Value) error
+}
+
+// Traverses recursively both values, assigning src's fields values to dst.
+// The map argument tracks comparisons that have already been seen, which allows
+// short circuiting on recursive types.
+func deepMerge(dst, src reflect.Value, visited map[uintptr]*visit, depth int, config *Config) (err error) {
+ overwrite := config.Overwrite
+ typeCheck := config.TypeCheck
+ overwriteWithEmptySrc := config.overwriteWithEmptyValue
+ overwriteSliceWithEmptySrc := config.overwriteSliceWithEmptyValue
+ sliceDeepCopy := config.sliceDeepCopy
+
+ if !src.IsValid() {
+ return
+ }
+ if dst.CanAddr() {
+ addr := dst.UnsafeAddr()
+ h := 17 * addr
+ seen := visited[h]
+ typ := dst.Type()
+ for p := seen; p != nil; p = p.next {
+ if p.ptr == addr && p.typ == typ {
+ return nil
+ }
+ }
+ // Remember, remember...
+ visited[h] = &visit{typ, seen, addr}
+ }
+
+ if config.Transformers != nil && !isReflectNil(dst) && dst.IsValid() {
+ if fn := config.Transformers.Transformer(dst.Type()); fn != nil {
+ err = fn(dst, src)
+ return
+ }
+ }
+
+ switch dst.Kind() {
+ case reflect.Struct:
+ if hasMergeableFields(dst) {
+ for i, n := 0, dst.NumField(); i < n; i++ {
+ if err = deepMerge(dst.Field(i), src.Field(i), visited, depth+1, config); err != nil {
+ return
+ }
+ }
+ } else {
+ if dst.CanSet() && (isReflectNil(dst) || overwrite) && (!isEmptyValue(src, !config.ShouldNotDereference) || overwriteWithEmptySrc) {
+ dst.Set(src)
+ }
+ }
+ case reflect.Map:
+ if dst.IsNil() && !src.IsNil() {
+ if dst.CanSet() {
+ dst.Set(reflect.MakeMap(dst.Type()))
+ } else {
+ dst = src
+ return
+ }
+ }
+
+ if src.Kind() != reflect.Map {
+ if overwrite && dst.CanSet() {
+ dst.Set(src)
+ }
+ return
+ }
+
+ for _, key := range src.MapKeys() {
+ srcElement := src.MapIndex(key)
+ if !srcElement.IsValid() {
+ continue
+ }
+ dstElement := dst.MapIndex(key)
+ switch srcElement.Kind() {
+ case reflect.Chan, reflect.Func, reflect.Map, reflect.Interface, reflect.Slice:
+ if srcElement.IsNil() {
+ if overwrite {
+ dst.SetMapIndex(key, srcElement)
+ }
+ continue
+ }
+ fallthrough
+ default:
+ if !srcElement.CanInterface() {
+ continue
+ }
+ switch reflect.TypeOf(srcElement.Interface()).Kind() {
+ case reflect.Struct:
+ fallthrough
+ case reflect.Ptr:
+ fallthrough
+ case reflect.Map:
+ srcMapElm := srcElement
+ dstMapElm := dstElement
+ if srcMapElm.CanInterface() {
+ srcMapElm = reflect.ValueOf(srcMapElm.Interface())
+ if dstMapElm.IsValid() {
+ dstMapElm = reflect.ValueOf(dstMapElm.Interface())
+ }
+ }
+ if err = deepMerge(dstMapElm, srcMapElm, visited, depth+1, config); err != nil {
+ return
+ }
+ case reflect.Slice:
+ srcSlice := reflect.ValueOf(srcElement.Interface())
+
+ var dstSlice reflect.Value
+ if !dstElement.IsValid() || dstElement.IsNil() {
+ dstSlice = reflect.MakeSlice(srcSlice.Type(), 0, srcSlice.Len())
+ } else {
+ dstSlice = reflect.ValueOf(dstElement.Interface())
+ }
+
+ if (!isEmptyValue(src, !config.ShouldNotDereference) || overwriteWithEmptySrc || overwriteSliceWithEmptySrc) && (overwrite || isEmptyValue(dst, !config.ShouldNotDereference)) && !config.AppendSlice && !sliceDeepCopy {
+ if typeCheck && srcSlice.Type() != dstSlice.Type() {
+ return fmt.Errorf("cannot override two slices with different type (%s, %s)", srcSlice.Type(), dstSlice.Type())
+ }
+ dstSlice = srcSlice
+ } else if config.AppendSlice {
+ if srcSlice.Type() != dstSlice.Type() {
+ return fmt.Errorf("cannot append two slices with different type (%s, %s)", srcSlice.Type(), dstSlice.Type())
+ }
+ dstSlice = reflect.AppendSlice(dstSlice, srcSlice)
+ } else if sliceDeepCopy {
+ i := 0
+ for ; i < srcSlice.Len() && i < dstSlice.Len(); i++ {
+ srcElement := srcSlice.Index(i)
+ dstElement := dstSlice.Index(i)
+
+ if srcElement.CanInterface() {
+ srcElement = reflect.ValueOf(srcElement.Interface())
+ }
+ if dstElement.CanInterface() {
+ dstElement = reflect.ValueOf(dstElement.Interface())
+ }
+
+ if err = deepMerge(dstElement, srcElement, visited, depth+1, config); err != nil {
+ return
+ }
+ }
+
+ }
+ dst.SetMapIndex(key, dstSlice)
+ }
+ }
+
+ if dstElement.IsValid() && !isEmptyValue(dstElement, !config.ShouldNotDereference) {
+ if reflect.TypeOf(srcElement.Interface()).Kind() == reflect.Slice {
+ continue
+ }
+ if reflect.TypeOf(srcElement.Interface()).Kind() == reflect.Map && reflect.TypeOf(dstElement.Interface()).Kind() == reflect.Map {
+ continue
+ }
+ }
+
+ if srcElement.IsValid() && ((srcElement.Kind() != reflect.Ptr && overwrite) || !dstElement.IsValid() || isEmptyValue(dstElement, !config.ShouldNotDereference)) {
+ if dst.IsNil() {
+ dst.Set(reflect.MakeMap(dst.Type()))
+ }
+ dst.SetMapIndex(key, srcElement)
+ }
+ }
+
+ // Ensure that all keys in dst are deleted if they are not in src.
+ if overwriteWithEmptySrc {
+ for _, key := range dst.MapKeys() {
+ srcElement := src.MapIndex(key)
+ if !srcElement.IsValid() {
+ dst.SetMapIndex(key, reflect.Value{})
+ }
+ }
+ }
+ case reflect.Slice:
+ if !dst.CanSet() {
+ break
+ }
+ if (!isEmptyValue(src, !config.ShouldNotDereference) || overwriteWithEmptySrc || overwriteSliceWithEmptySrc) && (overwrite || isEmptyValue(dst, !config.ShouldNotDereference)) && !config.AppendSlice && !sliceDeepCopy {
+ dst.Set(src)
+ } else if config.AppendSlice {
+ if src.Type() != dst.Type() {
+ return fmt.Errorf("cannot append two slice with different type (%s, %s)", src.Type(), dst.Type())
+ }
+ dst.Set(reflect.AppendSlice(dst, src))
+ } else if sliceDeepCopy {
+ for i := 0; i < src.Len() && i < dst.Len(); i++ {
+ srcElement := src.Index(i)
+ dstElement := dst.Index(i)
+ if srcElement.CanInterface() {
+ srcElement = reflect.ValueOf(srcElement.Interface())
+ }
+ if dstElement.CanInterface() {
+ dstElement = reflect.ValueOf(dstElement.Interface())
+ }
+
+ if err = deepMerge(dstElement, srcElement, visited, depth+1, config); err != nil {
+ return
+ }
+ }
+ }
+ case reflect.Ptr:
+ fallthrough
+ case reflect.Interface:
+ if isReflectNil(src) {
+ if overwriteWithEmptySrc && dst.CanSet() && src.Type().AssignableTo(dst.Type()) {
+ dst.Set(src)
+ }
+ break
+ }
+
+ if src.Kind() != reflect.Interface {
+ if dst.IsNil() || (src.Kind() != reflect.Ptr && overwrite) {
+ if dst.CanSet() && (overwrite || isEmptyValue(dst, !config.ShouldNotDereference)) {
+ dst.Set(src)
+ }
+ } else if src.Kind() == reflect.Ptr {
+ if !config.ShouldNotDereference {
+ if err = deepMerge(dst.Elem(), src.Elem(), visited, depth+1, config); err != nil {
+ return
+ }
+ } else {
+ if overwriteWithEmptySrc || (overwrite && !src.IsNil()) || dst.IsNil() {
+ dst.Set(src)
+ }
+ }
+ } else if dst.Elem().Type() == src.Type() {
+ if err = deepMerge(dst.Elem(), src, visited, depth+1, config); err != nil {
+ return
+ }
+ } else {
+ return ErrDifferentArgumentsTypes
+ }
+ break
+ }
+
+ if dst.IsNil() || overwrite {
+ if dst.CanSet() && (overwrite || isEmptyValue(dst, !config.ShouldNotDereference)) {
+ dst.Set(src)
+ }
+ break
+ }
+
+ if dst.Elem().Kind() == src.Elem().Kind() {
+ if err = deepMerge(dst.Elem(), src.Elem(), visited, depth+1, config); err != nil {
+ return
+ }
+ break
+ }
+ default:
+ mustSet := (isEmptyValue(dst, !config.ShouldNotDereference) || overwrite) && (!isEmptyValue(src, !config.ShouldNotDereference) || overwriteWithEmptySrc)
+ if mustSet {
+ if dst.CanSet() {
+ dst.Set(src)
+ } else {
+ dst = src
+ }
+ }
+ }
+
+ return
+}
+
+// Merge will fill any empty for value type attributes on the dst struct using corresponding
+// src attributes if they themselves are not empty. dst and src must be valid same-type structs
+// and dst must be a pointer to struct.
+// It won't merge unexported (private) fields and will do recursively any exported field.
+func Merge(dst, src interface{}, opts ...func(*Config)) error {
+ return merge(dst, src, opts...)
+}
+
+// MergeWithOverwrite will do the same as Merge except that non-empty dst attributes will be overridden by
+// non-empty src attribute values.
+// Deprecated: use Merge(…) with WithOverride
+func MergeWithOverwrite(dst, src interface{}, opts ...func(*Config)) error {
+ return merge(dst, src, append(opts, WithOverride)...)
+}
+
+// WithTransformers adds transformers to merge, allowing to customize the merging of some types.
+func WithTransformers(transformers Transformers) func(*Config) {
+ return func(config *Config) {
+ config.Transformers = transformers
+ }
+}
+
+// WithOverride will make merge override non-empty dst attributes with non-empty src attributes values.
+func WithOverride(config *Config) {
+ config.Overwrite = true
+}
+
+// WithOverwriteWithEmptyValue will make merge override non empty dst attributes with empty src attributes values.
+func WithOverwriteWithEmptyValue(config *Config) {
+ config.Overwrite = true
+ config.overwriteWithEmptyValue = true
+}
+
+// WithOverrideEmptySlice will make merge override empty dst slice with empty src slice.
+func WithOverrideEmptySlice(config *Config) {
+ config.overwriteSliceWithEmptyValue = true
+}
+
+// WithoutDereference prevents dereferencing pointers when evaluating whether they are empty
+// (i.e. a non-nil pointer is never considered empty).
+func WithoutDereference(config *Config) {
+ config.ShouldNotDereference = true
+}
+
+// WithAppendSlice will make merge append slices instead of overwriting it.
+func WithAppendSlice(config *Config) {
+ config.AppendSlice = true
+}
+
+// WithTypeCheck will make merge check types while overwriting it (must be used with WithOverride).
+func WithTypeCheck(config *Config) {
+ config.TypeCheck = true
+}
+
+// WithSliceDeepCopy will merge slice element one by one with Overwrite flag.
+func WithSliceDeepCopy(config *Config) {
+ config.sliceDeepCopy = true
+ config.Overwrite = true
+}
+
+func merge(dst, src interface{}, opts ...func(*Config)) error {
+ if dst != nil && reflect.ValueOf(dst).Kind() != reflect.Ptr {
+ return ErrNonPointerArgument
+ }
+ var (
+ vDst, vSrc reflect.Value
+ err error
+ )
+
+ config := &Config{}
+
+ for _, opt := range opts {
+ opt(config)
+ }
+
+ if vDst, vSrc, err = resolveValues(dst, src); err != nil {
+ return err
+ }
+ if vDst.Type() != vSrc.Type() {
+ return ErrDifferentArgumentsTypes
+ }
+ return deepMerge(vDst, vSrc, make(map[uintptr]*visit), 0, config)
+}
+
+// IsReflectNil is the reflect value provided nil
+func isReflectNil(v reflect.Value) bool {
+ k := v.Kind()
+ switch k {
+ case reflect.Interface, reflect.Slice, reflect.Chan, reflect.Func, reflect.Map, reflect.Ptr:
+ // Both interface and slice are nil if first word is 0.
+ // Both are always bigger than a word; assume flagIndir.
+ return v.IsNil()
+ default:
+ return false
+ }
+}