[Backport] Update to go-git v5.1.0 (#11936) (#11941)

* update go-git 5.0.0 -> v5.1.0

* vendor

Co-authored-by: techknowlogick <techknowlogick@gitea.io>

vendor/github.com/imdario/mergo/merge.go

@@ -0,0 +1,338 @@
+// 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"
+	"unsafe"
+)
+
+func hasExportedField(dst reflect.Value) (exported bool) {
+	for i, n := 0, dst.NumField(); i < n; i++ {
+		field := dst.Type().Field(i)
+		if isExportedComponent(&field) {
+			return true
+		}
+	}
+	return
+}
+
+func isExportedComponent(field *reflect.StructField) bool {
+	name := field.Name
+	pkgPath := field.PkgPath
+	if len(pkgPath) > 0 {
+		return false
+	}
+	c := name[0]
+	if 'a' <= c && c <= 'z' || c == '_' {
+		return false
+	}
+	return true
+}
+
+type Config struct {
+	Overwrite                    bool
+	AppendSlice                  bool
+	TypeCheck                    bool
+	Transformers                 Transformers
+	overwriteWithEmptyValue      bool
+	overwriteSliceWithEmptyValue 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(dstIn, src reflect.Value, visited map[uintptr]*visit, depth int, config *Config) (dst reflect.Value, err error) {
+	dst = dstIn
+	overwrite := config.Overwrite
+	typeCheck := config.TypeCheck
+	overwriteWithEmptySrc := config.overwriteWithEmptyValue
+	overwriteSliceWithEmptySrc := config.overwriteSliceWithEmptyValue
+
+	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 dst, nil
+			}
+		}
+		// Remember, remember...
+		visited[h] = &visit{addr, typ, seen}
+	}
+
+	if config.Transformers != nil && !isEmptyValue(dst) {
+		if fn := config.Transformers.Transformer(dst.Type()); fn != nil {
+			err = fn(dst, src)
+			return
+		}
+	}
+
+	if dst.IsValid() && src.IsValid() && src.Type() != dst.Type() {
+		err = fmt.Errorf("cannot append two different types (%s, %s)", src.Kind(), dst.Kind())
+		return
+	}
+
+	switch dst.Kind() {
+	case reflect.Struct:
+		if hasExportedField(dst) {
+			dstCp := reflect.New(dst.Type()).Elem()
+			for i, n := 0, dst.NumField(); i < n; i++ {
+				dstField := dst.Field(i)
+				structField := dst.Type().Field(i)
+				// copy un-exported struct fields
+				if !isExportedComponent(&structField) {
+					rf := dstCp.Field(i)
+					rf = reflect.NewAt(rf.Type(), unsafe.Pointer(rf.UnsafeAddr())).Elem() //nolint:gosec
+					dstRF := dst.Field(i)
+					if !dst.Field(i).CanAddr() {
+						continue
+					}
+
+					dstRF = reflect.NewAt(dstRF.Type(), unsafe.Pointer(dstRF.UnsafeAddr())).Elem() //nolint:gosec
+					rf.Set(dstRF)
+					continue
+				}
+				dstField, err = deepMerge(dstField, src.Field(i), visited, depth+1, config)
+				if err != nil {
+					return
+				}
+				dstCp.Field(i).Set(dstField)
+			}
+
+			if dst.CanSet() {
+				dst.Set(dstCp)
+			} else {
+				dst = dstCp
+			}
+			return
+		} else {
+			if (isReflectNil(dst) || overwrite) && (!isEmptyValue(src) || overwriteWithEmptySrc) {
+				dst = src
+			}
+		}
+
+	case reflect.Map:
+		if dst.IsNil() && !src.IsNil() {
+			if dst.CanSet() {
+				dst.Set(reflect.MakeMap(dst.Type()))
+			} else {
+				dst = src
+				return
+			}
+		}
+		for _, key := range src.MapKeys() {
+			srcElement := src.MapIndex(key)
+			dstElement := dst.MapIndex(key)
+			if !srcElement.IsValid() {
+				continue
+			}
+			if dst.MapIndex(key).IsValid() {
+				k := dstElement.Interface()
+				dstElement = reflect.ValueOf(k)
+			}
+			if isReflectNil(srcElement) {
+				if overwrite || isReflectNil(dstElement) {
+					dst.SetMapIndex(key, srcElement)
+				}
+				continue
+			}
+			if !srcElement.CanInterface() {
+				continue
+			}
+
+			if srcElement.CanInterface() {
+				srcElement = reflect.ValueOf(srcElement.Interface())
+				if dstElement.IsValid() {
+					dstElement = reflect.ValueOf(dstElement.Interface())
+				}
+			}
+			dstElement, err = deepMerge(dstElement, srcElement, visited, depth+1, config)
+			if err != nil {
+				return
+			}
+			dst.SetMapIndex(key, dstElement)
+
+		}
+	case reflect.Slice:
+		newSlice := dst
+		if (!isEmptyValue(src) || overwriteWithEmptySrc || overwriteSliceWithEmptySrc) && (overwrite || isEmptyValue(dst)) && !config.AppendSlice {
+			if typeCheck && src.Type() != dst.Type() {
+				return dst, fmt.Errorf("cannot override two slices with different type (%s, %s)", src.Type(), dst.Type())
+			}
+			newSlice = src
+		} else if config.AppendSlice {
+			if typeCheck && src.Type() != dst.Type() {
+				err = fmt.Errorf("cannot append two slice with different type (%s, %s)", src.Type(), dst.Type())
+				return
+			}
+			newSlice = reflect.AppendSlice(dst, src)
+		}
+		if dst.CanSet() {
+			dst.Set(newSlice)
+		} else {
+			dst = newSlice
+		}
+	case reflect.Ptr, reflect.Interface:
+		if isReflectNil(src) {
+			break
+		}
+
+		if dst.Kind() != reflect.Ptr && src.Type().AssignableTo(dst.Type()) {
+			if dst.IsNil() || overwrite {
+				if overwrite || isEmptyValue(dst) {
+					if dst.CanSet() {
+						dst.Set(src)
+					} else {
+						dst = src
+					}
+				}
+			}
+			break
+		}
+
+		if src.Kind() != reflect.Interface {
+			if dst.IsNil() || (src.Kind() != reflect.Ptr && overwrite) {
+				if dst.CanSet() && (overwrite || isEmptyValue(dst)) {
+					dst.Set(src)
+				}
+			} else if src.Kind() == reflect.Ptr {
+				if dst, err = deepMerge(dst.Elem(), src.Elem(), visited, depth+1, config); err != nil {
+					return
+				}
+				dst = dst.Addr()
+			} else if dst.Elem().Type() == src.Type() {
+				if dst, err = deepMerge(dst.Elem(), src, visited, depth+1, config); err != nil {
+					return
+				}
+			} else {
+				return dst, ErrDifferentArgumentsTypes
+			}
+			break
+		}
+		if dst.IsNil() || overwrite {
+			if (overwrite || isEmptyValue(dst)) && (overwriteWithEmptySrc || !isEmptyValue(src)) {
+				if dst.CanSet() {
+					dst.Set(src)
+				} else {
+					dst = src
+				}
+			}
+		} else if _, err = deepMerge(dst.Elem(), src.Elem(), visited, depth+1, config); err != nil {
+			return
+		}
+	default:
+		overwriteFull := (!isEmptyValue(src) || overwriteWithEmptySrc) && (overwrite || isEmptyValue(dst))
+		if overwriteFull {
+			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.overwriteWithEmptyValue = true
+}
+
+// WithOverrideEmptySlice will make merge override empty dst slice with empty src slice.
+func WithOverrideEmptySlice(config *Config) {
+	config.overwriteSliceWithEmptyValue = 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
+}
+
+func merge(dst, src interface{}, opts ...func(*Config)) error {
+	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.CanSet() {
+		return fmt.Errorf("cannot set dst, needs reference")
+	}
+	if vDst.Type() != vSrc.Type() {
+		return ErrDifferentArgumentsTypes
+	}
+	_, err = deepMerge(vDst, vSrc, make(map[uintptr]*visit), 0, config)
+	return err
+}
+
+// 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
+	}
+}