Use mattermost v5 module (#1192)

9 files changed, 290 insertions, 80 deletions

diff --git a/vendor/gopkg.in/ini.v1/.travis.yml b/vendor/gopkg.in/ini.v1/.travis.yml
index 149b7249..4db2e661 100644
--- a/vendor/gopkg.in/ini.v1/.travis.yml
+++ b/vendor/gopkg.in/ini.v1/.travis.yml
@@ -1,5 +1,6 @@
-sudo: false
 language: go
+os: linux
+dist: xenial
 go:
   - 1.6.x
   - 1.7.x
@@ -9,7 +10,7 @@ go:
   - 1.11.x
   - 1.12.x
   - 1.13.x
-
+  - 1.14.x
 install: skip
 script:
   - go get golang.org/x/tools/cmd/cover
diff --git a/vendor/gopkg.in/ini.v1/Makefile b/vendor/gopkg.in/ini.v1/Makefile
index af27ff07..f3b0dae2 100644
--- a/vendor/gopkg.in/ini.v1/Makefile
+++ b/vendor/gopkg.in/ini.v1/Makefile
@@ -6,7 +6,7 @@ test:
 	go test -v -cover -race
 
 bench:
-	go test -v -cover -race -test.bench=. -test.benchmem
+	go test -v -cover -test.bench=. -test.benchmem
 
 vet:
 	go vet
diff --git a/vendor/gopkg.in/ini.v1/README.md b/vendor/gopkg.in/ini.v1/README.md
index 3d6d3cfc..783eb06a 100644
--- a/vendor/gopkg.in/ini.v1/README.md
+++ b/vendor/gopkg.in/ini.v1/README.md
@@ -8,7 +8,7 @@ Package ini provides INI file read and write functionality in Go.
 
 ## Features
 
-- Load from multiple data sources(`[]byte`, file and `io.ReadCloser`) with overwrites.
+- Load from multiple data sources(file, `[]byte`, `io.Reader` and `io.ReadCloser`) with overwrites.
 - Read with recursion values.
 - Read with parent-child sections.
 - Read with auto-increment key names.
diff --git a/vendor/gopkg.in/ini.v1/data_source.go b/vendor/gopkg.in/ini.v1/data_source.go
index dc0277ec..bbedf361 100644
--- a/vendor/gopkg.in/ini.v1/data_source.go
+++ b/vendor/gopkg.in/ini.v1/data_source.go
@@ -66,6 +66,8 @@ func parseDataSource(source interface{}) (dataSource, error) {
 		return sourceFile{s}, nil
 	case []byte:
 		return &sourceData{s}, nil
+	case io.Reader:
+		return &sourceReadCloser{ioutil.NopCloser(s)}, nil
 	case io.ReadCloser:
 		return &sourceReadCloser{s}, nil
 	default:
diff --git a/vendor/gopkg.in/ini.v1/file.go b/vendor/gopkg.in/ini.v1/file.go
index 017b77c8..f95606f9 100644
--- a/vendor/gopkg.in/ini.v1/file.go
+++ b/vendor/gopkg.in/ini.v1/file.go
@@ -25,7 +25,7 @@ import (
 	"sync"
 )
 
-// File represents a combination of a or more INI file(s) in memory.
+// File represents a combination of one or more INI files in memory.
 type File struct {
 	options     LoadOptions
 	dataSources []dataSource
@@ -36,8 +36,12 @@ type File struct {
 
 	// To keep data in order.
 	sectionList []string
+	// To keep track of the index of a section with same name.
+	// This meta list is only used with non-unique section names are allowed.
+	sectionIndexes []int
+
 	// Actual data is stored here.
-	sections map[string]*Section
+	sections map[string][]*Section
 
 	NameMapper
 	ValueMapper
@@ -48,27 +52,37 @@ func newFile(dataSources []dataSource, opts LoadOptions) *File {
 	if len(opts.KeyValueDelimiters) == 0 {
 		opts.KeyValueDelimiters = "=:"
 	}
+	if len(opts.KeyValueDelimiterOnWrite) == 0 {
+		opts.KeyValueDelimiterOnWrite = "="
+	}
+
 	return &File{
 		BlockMode:   true,
 		dataSources: dataSources,
-		sections:    make(map[string]*Section),
-		sectionList: make([]string, 0, 10),
+		sections:    make(map[string][]*Section),
 		options:     opts,
 	}
 }
 
 // Empty returns an empty file object.
-func Empty() *File {
-	// Ignore error here, we sure our data is good.
-	f, _ := Load([]byte(""))
+func Empty(opts ...LoadOptions) *File {
+	var opt LoadOptions
+	if len(opts) > 0 {
+		opt = opts[0]
+	}
+
+	// Ignore error here, we are sure our data is good.
+	f, _ := LoadSources(opt, []byte(""))
 	return f
 }
 
 // NewSection creates a new section.
 func (f *File) NewSection(name string) (*Section, error) {
 	if len(name) == 0 {
-		return nil, errors.New("error creating new section: empty section name")
-	} else if f.options.Insensitive && name != DefaultSection {
+		return nil, errors.New("empty section name")
+	}
+
+	if f.options.Insensitive && name != DefaultSection {
 		name = strings.ToLower(name)
 	}
 
@@ -77,13 +91,20 @@ func (f *File) NewSection(name string) (*Section, error) {
 		defer f.lock.Unlock()
 	}
 
-	if inSlice(name, f.sectionList) {
-		return f.sections[name], nil
+	if !f.options.AllowNonUniqueSections && inSlice(name, f.sectionList) {
+		return f.sections[name][0], nil
 	}
 
 	f.sectionList = append(f.sectionList, name)
-	f.sections[name] = newSection(f, name)
-	return f.sections[name], nil
+
+	// NOTE: Append to indexes must happen before appending to sections,
+	// otherwise index will have off-by-one problem.
+	f.sectionIndexes = append(f.sectionIndexes, len(f.sections[name]))
+
+	sec := newSection(f, name)
+	f.sections[name] = append(f.sections[name], sec)
+
+	return sec, nil
 }
 
 // NewRawSection creates a new section with an unparseable body.
@@ -110,6 +131,16 @@ func (f *File) NewSections(names ...string) (err error) {
 
 // GetSection returns section by given name.
 func (f *File) GetSection(name string) (*Section, error) {
+	secs, err := f.SectionsByName(name)
+	if err != nil {
+		return nil, err
+	}
+
+	return secs[0], err
+}
+
+// SectionsByName returns all sections with given name.
+func (f *File) SectionsByName(name string) ([]*Section, error) {
 	if len(name) == 0 {
 		name = DefaultSection
 	}
@@ -122,11 +153,12 @@ func (f *File) GetSection(name string) (*Section, error) {
 		defer f.lock.RUnlock()
 	}
 
-	sec := f.sections[name]
-	if sec == nil {
-		return nil, fmt.Errorf("section '%s' does not exist", name)
+	secs := f.sections[name]
+	if len(secs) == 0 {
+		return nil, fmt.Errorf("section %q does not exist", name)
 	}
-	return sec, nil
+
+	return secs, nil
 }
 
 // Section assumes named section exists and returns a zero-value when not.
@@ -141,6 +173,19 @@ func (f *File) Section(name string) *Section {
 	return sec
 }
 
+// SectionWithIndex assumes named section exists and returns a new section when not.
+func (f *File) SectionWithIndex(name string, index int) *Section {
+	secs, err := f.SectionsByName(name)
+	if err != nil || len(secs) <= index {
+		// NOTE: It's OK here because the only possible error is empty section name,
+		// but if it's empty, this piece of code won't be executed.
+		newSec, _ := f.NewSection(name)
+		return newSec
+	}
+
+	return secs[index]
+}
+
 // Sections returns a list of Section stored in the current instance.
 func (f *File) Sections() []*Section {
 	if f.BlockMode {
@@ -150,7 +195,7 @@ func (f *File) Sections() []*Section {
 
 	sections := make([]*Section, len(f.sectionList))
 	for i, name := range f.sectionList {
-		sections[i] = f.sections[name]
+		sections[i] = f.sections[name][f.sectionIndexes[i]]
 	}
 	return sections
 }
@@ -167,24 +212,70 @@ func (f *File) SectionStrings() []string {
 	return list
 }
 
-// DeleteSection deletes a section.
+// DeleteSection deletes a section or all sections with given name.
 func (f *File) DeleteSection(name string) {
-	if f.BlockMode {
-		f.lock.Lock()
-		defer f.lock.Unlock()
+	secs, err := f.SectionsByName(name)
+	if err != nil {
+		return
+	}
+
+	for i := 0; i < len(secs); i++ {
+		// For non-unique sections, it is always needed to remove the first one so
+		// in the next iteration, the subsequent section continue having index 0.
+		// Ignoring the error as index 0 never returns an error.
+		_ = f.DeleteSectionWithIndex(name, 0)
+	}
+}
+
+// DeleteSectionWithIndex deletes a section with given name and index.
+func (f *File) DeleteSectionWithIndex(name string, index int) error {
+	if !f.options.AllowNonUniqueSections && index != 0 {
+		return fmt.Errorf("delete section with non-zero index is only allowed when non-unique sections is enabled")
 	}
 
 	if len(name) == 0 {
 		name = DefaultSection
 	}
+	if f.options.Insensitive {
+		name = strings.ToLower(name)
+	}
+
+	if f.BlockMode {
+		f.lock.Lock()
+		defer f.lock.Unlock()
+	}
+
+	// Count occurrences of the sections
+	occurrences := 0
+
+	sectionListCopy := make([]string, len(f.sectionList))
+	copy(sectionListCopy, f.sectionList)
+
+	for i, s := range sectionListCopy {
+		if s != name {
+			continue
+		}
 
-	for i, s := range f.sectionList {
-		if s == name {
+		if occurrences == index {
+			if len(f.sections[name]) <= 1 {
+				delete(f.sections, name) // The last one in the map
+			} else {
+				f.sections[name] = append(f.sections[name][:index], f.sections[name][index+1:]...)
+			}
+
+			// Fix section lists
 			f.sectionList = append(f.sectionList[:i], f.sectionList[i+1:]...)
-			delete(f.sections, name)
-			return
+			f.sectionIndexes = append(f.sectionIndexes[:i], f.sectionIndexes[i+1:]...)
+
+		} else if occurrences > index {
+			// Fix the indices of all following sections with this name.
+			f.sectionIndexes[i-1]--
 		}
+
+		occurrences++
 	}
+
+	return nil
 }
 
 func (f *File) reload(s dataSource) error {
@@ -203,7 +294,7 @@ func (f *File) Reload() (err error) {
 		if err = f.reload(s); err != nil {
 			// In loose mode, we create an empty default section for nonexistent files.
 			if os.IsNotExist(err) && f.options.Loose {
-				f.parse(bytes.NewBuffer(nil))
+				_ = f.parse(bytes.NewBuffer(nil))
 				continue
 			}
 			return err
@@ -230,16 +321,16 @@ func (f *File) Append(source interface{}, others ...interface{}) error {
 }
 
 func (f *File) writeToBuffer(indent string) (*bytes.Buffer, error) {
-	equalSign := DefaultFormatLeft + "=" + DefaultFormatRight
+	equalSign := DefaultFormatLeft + f.options.KeyValueDelimiterOnWrite + DefaultFormatRight
 
 	if PrettyFormat || PrettyEqual {
-		equalSign = " = "
+		equalSign = fmt.Sprintf(" %s ", f.options.KeyValueDelimiterOnWrite)
 	}
 
 	// Use buffer to make sure target is safe until finish encoding.
 	buf := bytes.NewBuffer(nil)
 	for i, sname := range f.sectionList {
-		sec := f.Section(sname)
+		sec := f.SectionWithIndex(sname, f.sectionIndexes[i])
 		if len(sec.Comment) > 0 {
 			// Support multiline comments
 			lines := strings.Split(sec.Comment, LineBreak)
@@ -282,7 +373,7 @@ func (f *File) writeToBuffer(indent string) (*bytes.Buffer, error) {
 		}
 
 		// Count and generate alignment length and buffer spaces using the
-		// longest key. Keys may be modifed if they contain certain characters so
+		// longest key. Keys may be modified if they contain certain characters so
 		// we need to take that into account in our calculation.
 		alignLength := 0
 		if PrettyFormat {
diff --git a/vendor/gopkg.in/ini.v1/ini.go b/vendor/gopkg.in/ini.v1/ini.go
index 945fc00c..9f28cb31 100644
--- a/vendor/gopkg.in/ini.v1/ini.go
+++ b/vendor/gopkg.in/ini.v1/ini.go
@@ -29,14 +29,8 @@ const (
 
 	// Maximum allowed depth when recursively substituing variable names.
 	depthValues = 99
-	version     = "1.51.0"
 )
 
-// Version returns current package version literal.
-func Version() string {
-	return version
-}
-
 var (
 	// LineBreak is the delimiter to determine or compose a new line.
 	// This variable will be changed to "\r\n" automatically on Windows at package init time.
@@ -109,12 +103,16 @@ type LoadOptions struct {
 	UnparseableSections []string
 	// KeyValueDelimiters is the sequence of delimiters that are used to separate key and value. By default, it is "=:".
 	KeyValueDelimiters string
+	// KeyValueDelimiters is the delimiter that are used to separate key and value output. By default, it is "=".
+	KeyValueDelimiterOnWrite string
 	// PreserveSurroundedQuote indicates whether to preserve surrounded quote (single and double quotes).
 	PreserveSurroundedQuote bool
 	// DebugFunc is called to collect debug information (currently only useful to debug parsing Python-style multiline values).
 	DebugFunc DebugFunc
 	// ReaderBufferSize is the buffer size of the reader in bytes.
 	ReaderBufferSize int
+	// AllowNonUniqueSections indicates whether to allow sections with the same name multiple times.
+	AllowNonUniqueSections bool
 }
 
 // DebugFunc is the type of function called to log parse events.
diff --git a/vendor/gopkg.in/ini.v1/parser.go b/vendor/gopkg.in/ini.v1/parser.go
index 53ab45c4..f023db59 100644
--- a/vendor/gopkg.in/ini.v1/parser.go
+++ b/vendor/gopkg.in/ini.v1/parser.go
@@ -181,7 +181,7 @@ func (p *parser) readMultilines(line, val, valQuote string) (string, error) {
 		}
 		val += next
 		if p.isEOF {
-			return "", fmt.Errorf("missing closing key quote from '%s' to '%s'", line, next)
+			return "", fmt.Errorf("missing closing key quote from %q to %q", line, next)
 		}
 	}
 	return val, nil
@@ -453,7 +453,7 @@ func (f *File) parse(reader io.Reader) (err error) {
 
 			section.Comment = strings.TrimSpace(p.comment.String())
 
-			// Reset aotu-counter and comments
+			// Reset auto-counter and comments
 			p.comment.Reset()
 			p.count = 1
 
diff --git a/vendor/gopkg.in/ini.v1/section.go b/vendor/gopkg.in/ini.v1/section.go
index 0bd3e130..6ba5ac29 100644
--- a/vendor/gopkg.in/ini.v1/section.go
+++ b/vendor/gopkg.in/ini.v1/section.go
@@ -131,7 +131,7 @@ func (s *Section) GetKey(name string) (*Key, error) {
 			}
 			break
 		}
-		return nil, fmt.Errorf("error when getting key of section '%s': key '%s' not exists", s.name, name)
+		return nil, fmt.Errorf("error when getting key of section %q: key %q not exists", s.name, name)
 	}
 	return key, nil
 }
@@ -249,7 +249,7 @@ func (s *Section) ChildSections() []*Section {
 	children := make([]*Section, 0, 3)
 	for _, name := range s.f.sectionList {
 		if strings.HasPrefix(name, prefix) {
-			children = append(children, s.f.sections[name])
+			children = append(children, s.f.sections[name]...)
 		}
 	}
 	return children
diff --git a/vendor/gopkg.in/ini.v1/struct.go b/vendor/gopkg.in/ini.v1/struct.go
index 6bc70e4d..6b958496 100644
--- a/vendor/gopkg.in/ini.v1/struct.go
+++ b/vendor/gopkg.in/ini.v1/struct.go
@@ -183,6 +183,10 @@ func setWithProperType(t reflect.Type, key *Key, field reflect.Value, delim stri
 		if vt.Name() == "Duration" {
 			durationVal, err := key.Duration()
 			if err != nil {
+				if intVal, err := key.Int64(); err == nil {
+					field.SetInt(intVal)
+					return nil
+				}
 				return wrapStrictError(err, isStrict)
 			}
 			if isPtr {
@@ -254,13 +258,13 @@ func setWithProperType(t reflect.Type, key *Key, field reflect.Value, delim stri
 	case reflect.Slice:
 		return setSliceWithProperType(key, field, delim, allowShadow, isStrict)
 	default:
-		return fmt.Errorf("unsupported type '%s'", t)
+		return fmt.Errorf("unsupported type %q", t)
 	}
 	return nil
 }
 
-func parseTagOptions(tag string) (rawName string, omitEmpty bool, allowShadow bool) {
-	opts := strings.SplitN(tag, ",", 3)
+func parseTagOptions(tag string) (rawName string, omitEmpty bool, allowShadow bool, allowNonUnique bool) {
+	opts := strings.SplitN(tag, ",", 4)
 	rawName = opts[0]
 	if len(opts) > 1 {
 		omitEmpty = opts[1] == "omitempty"
@@ -268,10 +272,13 @@ func parseTagOptions(tag string) (rawName string, omitEmpty bool, allowShadow bo
 	if len(opts) > 2 {
 		allowShadow = opts[2] == "allowshadow"
 	}
-	return rawName, omitEmpty, allowShadow
+	if len(opts) > 3 {
+		allowNonUnique = opts[3] == "nonunique"
+	}
+	return rawName, omitEmpty, allowShadow, allowNonUnique
 }
 
-func (s *Section) mapTo(val reflect.Value, isStrict bool) error {
+func (s *Section) mapToField(val reflect.Value, isStrict bool) error {
 	if val.Kind() == reflect.Ptr {
 		val = val.Elem()
 	}
@@ -286,7 +293,7 @@ func (s *Section) mapTo(val reflect.Value, isStrict bool) error {
 			continue
 		}
 
-		rawName, _, allowShadow := parseTagOptions(tag)
+		rawName, _, allowShadow, allowNonUnique := parseTagOptions(tag)
 		fieldName := s.parseFieldName(tpField.Name, rawName)
 		if len(fieldName) == 0 || !field.CanSet() {
 			continue
@@ -301,55 +308,92 @@ func (s *Section) mapTo(val reflect.Value, isStrict bool) error {
 
 		if isAnonymous || isStruct || isStructPtr {
 			if sec, err := s.f.GetSection(fieldName); err == nil {
-				// Only set the field to non-nil struct value if we have
-				// a section for it. Otherwise, we end up with a non-nil
-				// struct ptr even though there is no data.
+				// Only set the field to non-nil struct value if we have a section for it.
+				// Otherwise, we end up with a non-nil struct ptr even though there is no data.
 				if isStructPtr && field.IsNil() {
 					field.Set(reflect.New(tpField.Type.Elem()))
 				}
-				if err = sec.mapTo(field, isStrict); err != nil {
-					return fmt.Errorf("error mapping field(%s): %v", fieldName, err)
+				if err = sec.mapToField(field, isStrict); err != nil {
+					return fmt.Errorf("map to field %q: %v", fieldName, err)
 				}
 				continue
 			}
 		}
+
+		// Map non-unique sections
+		if allowNonUnique && tpField.Type.Kind() == reflect.Slice {
+			newField, err := s.mapToSlice(fieldName, field, isStrict)
+			if err != nil {
+				return fmt.Errorf("map to slice %q: %v", fieldName, err)
+			}
+
+			field.Set(newField)
+			continue
+		}
+
 		if key, err := s.GetKey(fieldName); err == nil {
 			delim := parseDelim(tpField.Tag.Get("delim"))
 			if err = setWithProperType(tpField.Type, key, field, delim, allowShadow, isStrict); err != nil {
-				return fmt.Errorf("error mapping field(%s): %v", fieldName, err)
+				return fmt.Errorf("set field %q: %v", fieldName, err)
 			}
 		}
 	}
 	return nil
 }
 
-// MapTo maps section to given struct.
-func (s *Section) MapTo(v interface{}) error {
+// mapToSlice maps all sections with the same name and returns the new value.
+// The type of the Value must be a slice.
+func (s *Section) mapToSlice(secName string, val reflect.Value, isStrict bool) (reflect.Value, error) {
+	secs, err := s.f.SectionsByName(secName)
+	if err != nil {
+		return reflect.Value{}, err
+	}
+
+	typ := val.Type().Elem()
+	for _, sec := range secs {
+		elem := reflect.New(typ)
+		if err = sec.mapToField(elem, isStrict); err != nil {
+			return reflect.Value{}, fmt.Errorf("map to field from section %q: %v", secName, err)
+		}
+
+		val = reflect.Append(val, elem.Elem())
+	}
+	return val, nil
+}
+
+// mapTo maps a section to object v.
+func (s *Section) mapTo(v interface{}, isStrict bool) error {
 	typ := reflect.TypeOf(v)
 	val := reflect.ValueOf(v)
 	if typ.Kind() == reflect.Ptr {
 		typ = typ.Elem()
 		val = val.Elem()
 	} else {
-		return errors.New("cannot map to non-pointer struct")
+		return errors.New("not a pointer to a struct")
 	}
 
-	return s.mapTo(val, false)
+	if typ.Kind() == reflect.Slice {
+		newField, err := s.mapToSlice(s.name, val, isStrict)
+		if err != nil {
+			return err
+		}
+
+		val.Set(newField)
+		return nil
+	}
+
+	return s.mapToField(val, isStrict)
+}
+
+// MapTo maps section to given struct.
+func (s *Section) MapTo(v interface{}) error {
+	return s.mapTo(v, false)
 }
 
 // StrictMapTo maps section to given struct in strict mode,
 // which returns all possible error including value parsing error.
 func (s *Section) StrictMapTo(v interface{}) error {
-	typ := reflect.TypeOf(v)
-	val := reflect.ValueOf(v)
-	if typ.Kind() == reflect.Ptr {
-		typ = typ.Elem()
-		val = val.Elem()
-	} else {
-		return errors.New("cannot map to non-pointer struct")
-	}
-
-	return s.mapTo(val, true)
+	return s.mapTo(v, true)
 }
 
 // MapTo maps file to given struct.
@@ -427,7 +471,7 @@ func reflectSliceWithProperType(key *Key, field reflect.Value, delim string, all
 			if i == 0 {
 				keyWithShadows = newKey(key.s, key.name, val)
 			} else {
-				keyWithShadows.AddShadow(val)
+				_ = keyWithShadows.AddShadow(val)
 			}
 		}
 		key = keyWithShadows
@@ -480,7 +524,7 @@ func reflectWithProperType(t reflect.Type, key *Key, field reflect.Value, delim
 			return reflectWithProperType(t.Elem(), key, field.Elem(), delim, allowShadow)
 		}
 	default:
-		return fmt.Errorf("unsupported type '%s'", t)
+		return fmt.Errorf("unsupported type %q", t)
 	}
 	return nil
 }
@@ -508,6 +552,11 @@ func isEmptyValue(v reflect.Value) bool {
 	return false
 }
 
+// StructReflector is the interface implemented by struct types that can extract themselves into INI objects.
+type StructReflector interface {
+	ReflectINIStruct(*File) error
+}
+
 func (s *Section) reflectFrom(val reflect.Value) error {
 	if val.Kind() == reflect.Ptr {
 		val = val.Elem()
@@ -523,11 +572,15 @@ func (s *Section) reflectFrom(val reflect.Value) error {
 			continue
 		}
 
-		rawName, omitEmpty, allowShadow := parseTagOptions(tag)
+		rawName, omitEmpty, allowShadow, allowNonUnique := parseTagOptions(tag)
 		if omitEmpty && isEmptyValue(field) {
 			continue
 		}
 
+		if r, ok := field.Interface().(StructReflector); ok {
+			return r.ReflectINIStruct(s.f)
+		}
+
 		fieldName := s.parseFieldName(tpField.Name, rawName)
 		if len(fieldName) == 0 || !field.CanSet() {
 			continue
@@ -548,12 +601,41 @@ func (s *Section) reflectFrom(val reflect.Value) error {
 			}
 
 			if err = sec.reflectFrom(field); err != nil {
-				return fmt.Errorf("error reflecting field (%s): %v", fieldName, err)
+				return fmt.Errorf("reflect from field %q: %v", fieldName, err)
+			}
+			continue
+		}
+
+		if allowNonUnique && tpField.Type.Kind() == reflect.Slice {
+			slice := field.Slice(0, field.Len())
+			if field.Len() == 0 {
+				return nil
+			}
+			sliceOf := field.Type().Elem().Kind()
+
+			for i := 0; i < field.Len(); i++ {
+				if sliceOf != reflect.Struct && sliceOf != reflect.Ptr {
+					return fmt.Errorf("field %q is not a slice of pointer or struct", fieldName)
+				}
+
+				sec, err := s.f.NewSection(fieldName)
+				if err != nil {
+					return err
+				}
+
+				// Add comment from comment tag
+				if len(sec.Comment) == 0 {
+					sec.Comment = tpField.Tag.Get("comment")
+				}
+
+				if err := sec.reflectFrom(slice.Index(i)); err != nil {
+					return fmt.Errorf("reflect from field %q: %v", fieldName, err)
+				}
 			}
 			continue
 		}
 
-		// Note: Same reason as secion.
+		// Note: Same reason as section.
 		key, err := s.GetKey(fieldName)
 		if err != nil {
 			key, _ = s.NewKey(fieldName, "")
@@ -564,23 +646,59 @@ func (s *Section) reflectFrom(val reflect.Value) error {
 			key.Comment = tpField.Tag.Get("comment")
 		}
 
-		if err = reflectWithProperType(tpField.Type, key, field, parseDelim(tpField.Tag.Get("delim")), allowShadow); err != nil {
-			return fmt.Errorf("error reflecting field (%s): %v", fieldName, err)
+		delim := parseDelim(tpField.Tag.Get("delim"))
+		if err = reflectWithProperType(tpField.Type, key, field, delim, allowShadow); err != nil {
+			return fmt.Errorf("reflect field %q: %v", fieldName, err)
 		}
 
 	}
 	return nil
 }
 
-// ReflectFrom reflects secion from given struct.
+// ReflectFrom reflects section from given struct. It overwrites existing ones.
 func (s *Section) ReflectFrom(v interface{}) error {
 	typ := reflect.TypeOf(v)
 	val := reflect.ValueOf(v)
+
+	if s.name != DefaultSection && s.f.options.AllowNonUniqueSections &&
+		(typ.Kind() == reflect.Slice || typ.Kind() == reflect.Ptr) {
+		// Clear sections to make sure none exists before adding the new ones
+		s.f.DeleteSection(s.name)
+
+		if typ.Kind() == reflect.Ptr {
+			sec, err := s.f.NewSection(s.name)
+			if err != nil {
+				return err
+			}
+			return sec.reflectFrom(val.Elem())
+		}
+
+		slice := val.Slice(0, val.Len())
+		sliceOf := val.Type().Elem().Kind()
+		if sliceOf != reflect.Ptr {
+			return fmt.Errorf("not a slice of pointers")
+		}
+
+		for i := 0; i < slice.Len(); i++ {
+			sec, err := s.f.NewSection(s.name)
+			if err != nil {
+				return err
+			}
+
+			err = sec.reflectFrom(slice.Index(i))
+			if err != nil {
+				return fmt.Errorf("reflect from %dth field: %v", i, err)
+			}
+		}
+
+		return nil
+	}
+
 	if typ.Kind() == reflect.Ptr {
 		typ = typ.Elem()
 		val = val.Elem()
 	} else {
-		return errors.New("cannot reflect from non-pointer struct")
+		return errors.New("not a pointer to a struct")
 	}
 
 	return s.reflectFrom(val)