source/vendor/github.com/emirpasic/gods/lists/lists.go

+// Copyright (c) 2015, Emir Pasic. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package lists provides an abstract List interface.
+//
+// In computer science, a list or sequence is an abstract data type that represents an ordered sequence of values, where the same value may occur more than once. An instance of a list is a computer representation of the mathematical concept of a finite sequence; the (potentially) infinite analog of a list is a stream.  Lists are a basic example of containers, as they contain other values. If the same value occurs multiple times, each occurrence is considered a distinct item.
+//
+// Reference: https://en.wikipedia.org/wiki/List_%28abstract_data_type%29
+package lists
+
+import (
+	"github.com/emirpasic/gods/containers"
+	"github.com/emirpasic/gods/utils"
+)
+
+// List interface that all lists implement
+type List interface {
+	Get(index int) (interface{}, bool)
+	Remove(index int)
+	Add(values ...interface{})
+	Contains(values ...interface{}) bool
+	Sort(comparator utils.Comparator)
+	Swap(index1, index2 int)
+	Insert(index int, values ...interface{})
+	Set(index int, value interface{})
+
+	containers.Container
+	// Empty() bool
+	// Size() int
+	// Clear()
+	// Values() []interface{}
+	// String() string
+}

source/vendor/github.com/emirpasic/gods/trees/binaryheap/binaryheap.go

+// Copyright (c) 2015, Emir Pasic. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package binaryheap implements a binary heap backed by array list.
+//
+// Comparator defines this heap as either min or max heap.
+//
+// Structure is not thread safe.
+//
+// References: http://en.wikipedia.org/wiki/Binary_heap
+package binaryheap
+
+import (
+	"fmt"
+	"github.com/emirpasic/gods/lists/arraylist"
+	"github.com/emirpasic/gods/trees"
+	"github.com/emirpasic/gods/utils"
+	"strings"
+)
+
+// Assert Tree implementation
+var _ trees.Tree = (*Heap)(nil)
+
+// Heap holds elements in an array-list
+type Heap struct {
+	list       *arraylist.List
+	Comparator utils.Comparator
+}
+
+// NewWith instantiates a new empty heap tree with the custom comparator.
+func NewWith(comparator utils.Comparator) *Heap {
+	return &Heap{list: arraylist.New(), Comparator: comparator}
+}
+
+// NewWithIntComparator instantiates a new empty heap with the IntComparator, i.e. elements are of type int.
+func NewWithIntComparator() *Heap {
+	return &Heap{list: arraylist.New(), Comparator: utils.IntComparator}
+}
+
+// NewWithStringComparator instantiates a new empty heap with the StringComparator, i.e. elements are of type string.
+func NewWithStringComparator() *Heap {
+	return &Heap{list: arraylist.New(), Comparator: utils.StringComparator}
+}
+
+// Push adds a value onto the heap and bubbles it up accordingly.
+func (heap *Heap) Push(values ...interface{}) {
+	if len(values) == 1 {
+		heap.list.Add(values[0])
+		heap.bubbleUp()
+	} else {
+		// Reference: https://en.wikipedia.org/wiki/Binary_heap#Building_a_heap
+		for _, value := range values {
+			heap.list.Add(value)
+		}
+		size := heap.list.Size()/2 + 1
+		for i := size; i >= 0; i-- {
+			heap.bubbleDownIndex(i)
+		}
+	}
+}
+
+// Pop removes top element on heap and returns it, or nil if heap is empty.
+// Second return parameter is true, unless the heap was empty and there was nothing to pop.
+func (heap *Heap) Pop() (value interface{}, ok bool) {
+	value, ok = heap.list.Get(0)
+	if !ok {
+		return
+	}
+	lastIndex := heap.list.Size() - 1
+	heap.list.Swap(0, lastIndex)
+	heap.list.Remove(lastIndex)
+	heap.bubbleDown()
+	return
+}
+
+// Peek returns top element on the heap without removing it, or nil if heap is empty.
+// Second return parameter is true, unless the heap was empty and there was nothing to peek.
+func (heap *Heap) Peek() (value interface{}, ok bool) {
+	return heap.list.Get(0)
+}
+
+// Empty returns true if heap does not contain any elements.
+func (heap *Heap) Empty() bool {
+	return heap.list.Empty()
+}
+
+// Size returns number of elements within the heap.
+func (heap *Heap) Size() int {
+	return heap.list.Size()
+}
+
+// Clear removes all elements from the heap.
+func (heap *Heap) Clear() {
+	heap.list.Clear()
+}
+
+// Values returns all elements in the heap.
+func (heap *Heap) Values() []interface{} {
+	values := make([]interface{}, heap.list.Size(), heap.list.Size())
+	for it := heap.Iterator(); it.Next(); {
+		values[it.Index()] = it.Value()
+	}
+	return values
+}
+
+// String returns a string representation of container
+func (heap *Heap) String() string {
+	str := "BinaryHeap\n"
+	values := []string{}
+	for it := heap.Iterator(); it.Next(); {
+		values = append(values, fmt.Sprintf("%v", it.Value()))
+	}
+	str += strings.Join(values, ", ")
+	return str
+}
+
+// Performs the "bubble down" operation. This is to place the element that is at the root
+// of the heap in its correct place so that the heap maintains the min/max-heap order property.
+func (heap *Heap) bubbleDown() {
+	heap.bubbleDownIndex(0)
+}
+
+// Performs the "bubble down" operation. This is to place the element that is at the index
+// of the heap in its correct place so that the heap maintains the min/max-heap order property.
+func (heap *Heap) bubbleDownIndex(index int) {
+	size := heap.list.Size()
+	for leftIndex := index<<1 + 1; leftIndex < size; leftIndex = index<<1 + 1 {
+		rightIndex := index<<1 + 2
+		smallerIndex := leftIndex
+		leftValue, _ := heap.list.Get(leftIndex)
+		rightValue, _ := heap.list.Get(rightIndex)
+		if rightIndex < size && heap.Comparator(leftValue, rightValue) > 0 {
+			smallerIndex = rightIndex
+		}
+		indexValue, _ := heap.list.Get(index)
+		smallerValue, _ := heap.list.Get(smallerIndex)
+		if heap.Comparator(indexValue, smallerValue) > 0 {
+			heap.list.Swap(index, smallerIndex)
+		} else {
+			break
+		}
+		index = smallerIndex
+	}
+}
+
+// Performs the "bubble up" operation. This is to place a newly inserted
+// element (i.e. last element in the list) in its correct place so that
+// the heap maintains the min/max-heap order property.
+func (heap *Heap) bubbleUp() {
+	index := heap.list.Size() - 1
+	for parentIndex := (index - 1) >> 1; index > 0; parentIndex = (index - 1) >> 1 {
+		indexValue, _ := heap.list.Get(index)
+		parentValue, _ := heap.list.Get(parentIndex)
+		if heap.Comparator(parentValue, indexValue) <= 0 {
+			break
+		}
+		heap.list.Swap(index, parentIndex)
+		index = parentIndex
+	}
+}
+
+// Check that the index is within bounds of the list
+func (heap *Heap) withinRange(index int) bool {
+	return index >= 0 && index < heap.list.Size()
+}

source/vendor/github.com/emirpasic/gods/trees/binaryheap/iterator.go

+// Copyright (c) 2015, Emir Pasic. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package binaryheap
+
+import (
+	"github.com/emirpasic/gods/containers"
+)
+
+// Assert Iterator implementation
+var _ containers.ReverseIteratorWithIndex = (*Iterator)(nil)
+
+// Iterator returns a stateful iterator whose values can be fetched by an index.
+type Iterator struct {
+	heap  *Heap
+	index int
+}
+
+// Iterator returns a stateful iterator whose values can be fetched by an index.
+func (heap *Heap) Iterator() Iterator {
+	return Iterator{heap: heap, index: -1}
+}
+
+// Next moves the iterator to the next element and returns true if there was a next element in the container.
+// If Next() returns true, then next element's index and value can be retrieved by Index() and Value().
+// If Next() was called for the first time, then it will point the iterator to the first element if it exists.
+// Modifies the state of the iterator.
+func (iterator *Iterator) Next() bool {
+	if iterator.index < iterator.heap.Size() {
+		iterator.index++
+	}
+	return iterator.heap.withinRange(iterator.index)
+}
+
+// Prev moves the iterator to the previous element and returns true if there was a previous element in the container.
+// If Prev() returns true, then previous element's index and value can be retrieved by Index() and Value().
+// Modifies the state of the iterator.
+func (iterator *Iterator) Prev() bool {
+	if iterator.index >= 0 {
+		iterator.index--
+	}
+	return iterator.heap.withinRange(iterator.index)
+}
+
+// Value returns the current element's value.
+// Does not modify the state of the iterator.
+func (iterator *Iterator) Value() interface{} {
+	start, end := evaluateRange(iterator.index)
+	if end > iterator.heap.Size() {
+		end = iterator.heap.Size()
+	}
+	tmpHeap := NewWith(iterator.heap.Comparator)
+	for n := start; n < end; n++ {
+		value, _ := iterator.heap.list.Get(n)
+		tmpHeap.Push(value)
+	}
+	for n := 0; n < iterator.index-start; n++ {
+		tmpHeap.Pop()
+	}
+	value, _ := tmpHeap.Pop()
+	return value
+}
+
+// Index returns the current element's index.
+// Does not modify the state of the iterator.
+func (iterator *Iterator) Index() int {
+	return iterator.index
+}
+
+// Begin resets the iterator to its initial state (one-before-first)
+// Call Next() to fetch the first element if any.
+func (iterator *Iterator) Begin() {
+	iterator.index = -1
+}
+
+// End moves the iterator past the last element (one-past-the-end).
+// Call Prev() to fetch the last element if any.
+func (iterator *Iterator) End() {
+	iterator.index = iterator.heap.Size()
+}
+
+// First moves the iterator to the first element and returns true if there was a first element in the container.
+// If First() returns true, then first element's index and value can be retrieved by Index() and Value().
+// Modifies the state of the iterator.
+func (iterator *Iterator) First() bool {
+	iterator.Begin()
+	return iterator.Next()
+}
+
+// Last moves the iterator to the last element and returns true if there was a last element in the container.
+// If Last() returns true, then last element's index and value can be retrieved by Index() and Value().
+// Modifies the state of the iterator.
+func (iterator *Iterator) Last() bool {
+	iterator.End()
+	return iterator.Prev()
+}
+
+// NextTo moves the iterator to the next element from current position that satisfies the condition given by the
+// passed function, and returns true if there was a next element in the container.
+// If NextTo() returns true, then next element's index and value can be retrieved by Index() and Value().
+// Modifies the state of the iterator.
+func (iterator *Iterator) NextTo(f func(index int, value interface{}) bool) bool {
+	for iterator.Next() {
+		index, value := iterator.Index(), iterator.Value()
+		if f(index, value) {
+			return true
+		}
+	}
+	return false
+}
+
+// PrevTo moves the iterator to the previous element from current position that satisfies the condition given by the
+// passed function, and returns true if there was a next element in the container.
+// If PrevTo() returns true, then next element's index and value can be retrieved by Index() and Value().
+// Modifies the state of the iterator.
+func (iterator *Iterator) PrevTo(f func(index int, value interface{}) bool) bool {
+	for iterator.Prev() {
+		index, value := iterator.Index(), iterator.Value()
+		if f(index, value) {
+			return true
+		}
+	}
+	return false
+}
+
+// numOfBits counts the number of bits of an int
+func numOfBits(n int) uint {
+	var count uint
+	for n != 0 {
+		count++
+		n >>= 1
+	}
+	return count
+}
+
+// evaluateRange evaluates the index range [start,end) of same level nodes in the heap as the index
+func evaluateRange(index int) (start int, end int) {
+	bits := numOfBits(index+1) - 1
+	start = 1<<bits - 1
+	end = start + 1<<bits
+	return
+}

source/vendor/github.com/emirpasic/gods/trees/binaryheap/serialization.go

+// Copyright (c) 2015, Emir Pasic. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package binaryheap
+
+import (
+	"github.com/emirpasic/gods/containers"
+)
+
+// Assert Serialization implementation
+var _ containers.JSONSerializer = (*Heap)(nil)
+var _ containers.JSONDeserializer = (*Heap)(nil)
+
+// ToJSON outputs the JSON representation of the heap.
+func (heap *Heap) ToJSON() ([]byte, error) {
+	return heap.list.ToJSON()
+}
+
+// FromJSON populates the heap from the input JSON representation.
+func (heap *Heap) FromJSON(data []byte) error {
+	return heap.list.FromJSON(data)
+}
+
+// UnmarshalJSON @implements json.Unmarshaler
+func (heap *Heap) UnmarshalJSON(bytes []byte) error {
+	return heap.FromJSON(bytes)
+}
+
+// MarshalJSON @implements json.Marshaler
+func (heap *Heap) MarshalJSON() ([]byte, error) {
+	return heap.ToJSON()
+}

source/vendor/github.com/emirpasic/gods/trees/trees.go

+// Copyright (c) 2015, Emir Pasic. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package trees provides an abstract Tree interface.
+//
+// In computer science, a tree is a widely used abstract data type (ADT) or data structure implementing this ADT that simulates a hierarchical tree structure, with a root value and subtrees of children with a parent node, represented as a set of linked nodes.
+//
+// Reference: https://en.wikipedia.org/wiki/Tree_%28data_structure%29
+package trees
+
+import "github.com/emirpasic/gods/containers"
+
+// Tree interface that all trees implement
+type Tree interface {
+	containers.Container
+	// Empty() bool
+	// Size() int
+	// Clear()
+	// Values() []interface{}
+	// String() string
+}

source/vendor/github.com/emirpasic/gods/utils/comparator.go

+// Copyright (c) 2015, Emir Pasic. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package utils
+
+import "time"
+
+// Comparator will make type assertion (see IntComparator for example),
+// which will panic if a or b are not of the asserted type.
+//
+// Should return a number:
+//    negative , if a < b
+//    zero     , if a == b
+//    positive , if a > b
+type Comparator func(a, b interface{}) int
+
+// StringComparator provides a fast comparison on strings
+func StringComparator(a, b interface{}) int {
+	s1 := a.(string)
+	s2 := b.(string)
+	min := len(s2)
+	if len(s1) < len(s2) {
+		min = len(s1)
+	}
+	diff := 0
+	for i := 0; i < min && diff == 0; i++ {
+		diff = int(s1[i]) - int(s2[i])
+	}
+	if diff == 0 {
+		diff = len(s1) - len(s2)
+	}
+	if diff < 0 {
+		return -1
+	}
+	if diff > 0 {
+		return 1
+	}
+	return 0
+}
+
+// IntComparator provides a basic comparison on int
+func IntComparator(a, b interface{}) int {
+	aAsserted := a.(int)
+	bAsserted := b.(int)
+	switch {
+	case aAsserted > bAsserted:
+		return 1
+	case aAsserted < bAsserted:
+		return -1
+	default:
+		return 0
+	}
+}
+
+// Int8Comparator provides a basic comparison on int8
+func Int8Comparator(a, b interface{}) int {
+	aAsserted := a.(int8)
+	bAsserted := b.(int8)
+	switch {
+	case aAsserted > bAsserted:
+		return 1
+	case aAsserted < bAsserted:
+		return -1
+	default:
+		return 0
+	}
+}
+
+// Int16Comparator provides a basic comparison on int16
+func Int16Comparator(a, b interface{}) int {
+	aAsserted := a.(int16)
+	bAsserted := b.(int16)
+	switch {
+	case aAsserted > bAsserted:
+		return 1
+	case aAsserted < bAsserted:
+		return -1
+	default:
+		return 0
+	}
+}
+
+// Int32Comparator provides a basic comparison on int32
+func Int32Comparator(a, b interface{}) int {
+	aAsserted := a.(int32)
+	bAsserted := b.(int32)
+	switch {
+	case aAsserted > bAsserted:
+		return 1
+	case aAsserted < bAsserted:
+		return -1
+	default:
+		return 0
+	}
+}
+
+// Int64Comparator provides a basic comparison on int64
+func Int64Comparator(a, b interface{}) int {
+	aAsserted := a.(int64)
+	bAsserted := b.(int64)
+	switch {
+	case aAsserted > bAsserted:
+		return 1
+	case aAsserted < bAsserted:
+		return -1
+	default:
+		return 0
+	}
+}
+
+// UIntComparator provides a basic comparison on uint
+func UIntComparator(a, b interface{}) int {
+	aAsserted := a.(uint)
+	bAsserted := b.(uint)
+	switch {
+	case aAsserted > bAsserted:
+		return 1
+	case aAsserted < bAsserted:
+		return -1
+	default:
+		return 0
+	}
+}
+
+// UInt8Comparator provides a basic comparison on uint8
+func UInt8Comparator(a, b interface{}) int {
+	aAsserted := a.(uint8)
+	bAsserted := b.(uint8)
+	switch {
+	case aAsserted > bAsserted:
+		return 1
+	case aAsserted < bAsserted:
+		return -1
+	default:
+		return 0
+	}
+}
+
+// UInt16Comparator provides a basic comparison on uint16
+func UInt16Comparator(a, b interface{}) int {
+	aAsserted := a.(uint16)
+	bAsserted := b.(uint16)
+	switch {
+	case aAsserted > bAsserted:
+		return 1
+	case aAsserted < bAsserted:
+		return -1
+	default:
+		return 0
+	}
+}
+
+// UInt32Comparator provides a basic comparison on uint32
+func UInt32Comparator(a, b interface{}) int {
+	aAsserted := a.(uint32)
+	bAsserted := b.(uint32)
+	switch {
+	case aAsserted > bAsserted:
+		return 1
+	case aAsserted < bAsserted:
+		return -1
+	default:
+		return 0
+	}
+}
+
+// UInt64Comparator provides a basic comparison on uint64
+func UInt64Comparator(a, b interface{}) int {
+	aAsserted := a.(uint64)
+	bAsserted := b.(uint64)
+	switch {
+	case aAsserted > bAsserted:
+		return 1
+	case aAsserted < bAsserted:
+		return -1
+	default:
+		return 0
+	}
+}
+
+// Float32Comparator provides a basic comparison on float32
+func Float32Comparator(a, b interface{}) int {
+	aAsserted := a.(float32)
+	bAsserted := b.(float32)
+	switch {
+	case aAsserted > bAsserted:
+		return 1
+	case aAsserted < bAsserted:
+		return -1
+	default:
+		return 0
+	}
+}
+
+// Float64Comparator provides a basic comparison on float64
+func Float64Comparator(a, b interface{}) int {
+	aAsserted := a.(float64)
+	bAsserted := b.(float64)
+	switch {
+	case aAsserted > bAsserted:
+		return 1
+	case aAsserted < bAsserted:
+		return -1
+	default:
+		return 0
+	}
+}
+
+// ByteComparator provides a basic comparison on byte
+func ByteComparator(a, b interface{}) int {
+	aAsserted := a.(byte)
+	bAsserted := b.(byte)
+	switch {
+	case aAsserted > bAsserted:
+		return 1
+	case aAsserted < bAsserted:
+		return -1
+	default:
+		return 0
+	}
+}
+
+// RuneComparator provides a basic comparison on rune
+func RuneComparator(a, b interface{}) int {
+	aAsserted := a.(rune)
+	bAsserted := b.(rune)
+	switch {
+	case aAsserted > bAsserted:
+		return 1
+	case aAsserted < bAsserted:
+		return -1
+	default:
+		return 0
+	}
+}
+
+// TimeComparator provides a basic comparison on time.Time
+func TimeComparator(a, b interface{}) int {
+	aAsserted := a.(time.Time)
+	bAsserted := b.(time.Time)
+
+	switch {
+	case aAsserted.After(bAsserted):
+		return 1
+	case aAsserted.Before(bAsserted):
+		return -1
+	default:
+		return 0
+	}
+}

source/vendor/github.com/emirpasic/gods/utils/sort.go

+// Copyright (c) 2015, Emir Pasic. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package utils
+
+import "sort"
+
+// Sort sorts values (in-place) with respect to the given comparator.
+//
+// Uses Go's sort (hybrid of quicksort for large and then insertion sort for smaller slices).
+func Sort(values []interface{}, comparator Comparator) {
+	sort.Sort(sortable{values, comparator})
+}
+
+type sortable struct {
+	values     []interface{}
+	comparator Comparator
+}
+
+func (s sortable) Len() int {
+	return len(s.values)
+}
+func (s sortable) Swap(i, j int) {
+	s.values[i], s.values[j] = s.values[j], s.values[i]
+}
+func (s sortable) Less(i, j int) bool {
+	return s.comparator(s.values[i], s.values[j]) < 0
+}

source/vendor/github.com/emirpasic/gods/utils/utils.go

+// Copyright (c) 2015, Emir Pasic. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package utils provides common utility functions.
+//
+// Provided functionalities:
+// - sorting
+// - comparators
+package utils
+
+import (
+	"fmt"
+	"strconv"
+)
+
+// ToString converts a value to string.
+func ToString(value interface{}) string {
+	switch value := value.(type) {
+	case string:
+		return value
+	case int8:
+		return strconv.FormatInt(int64(value), 10)
+	case int16:
+		return strconv.FormatInt(int64(value), 10)
+	case int32:
+		return strconv.FormatInt(int64(value), 10)
+	case int64:
+		return strconv.FormatInt(value, 10)
+	case uint8:
+		return strconv.FormatUint(uint64(value), 10)
+	case uint16:
+		return strconv.FormatUint(uint64(value), 10)
+	case uint32:
+		return strconv.FormatUint(uint64(value), 10)
+	case uint64:
+		return strconv.FormatUint(value, 10)
+	case float32:
+		return strconv.FormatFloat(float64(value), 'g', -1, 64)
+	case float64:
+		return strconv.FormatFloat(value, 'g', -1, 64)
+	case bool:
+		return strconv.FormatBool(value)
+	default:
+		return fmt.Sprintf("%+v", value)
+	}
+}

source/vendor/github.com/go-git/gcfg/.gitignore

+coverage.out

source/vendor/github.com/go-git/gcfg/LICENSE

+Copyright (c) 2012 Péter Surányi. Portions Copyright (c) 2009 The Go
+Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

source/vendor/github.com/go-git/gcfg/Makefile

+# General
+WORKDIR = $(PWD)
+
+# Go parameters
+GOCMD = go
+GOTEST = $(GOCMD) test
+
+# Coverage
+COVERAGE_REPORT = coverage.out
+COVERAGE_MODE = count
+
+test:
+	$(GOTEST) ./...
+
+test-coverage:
+	echo "" > $(COVERAGE_REPORT); \
+	$(GOTEST) -coverprofile=$(COVERAGE_REPORT) -coverpkg=./... -covermode=$(COVERAGE_MODE) ./...

source/vendor/github.com/go-git/gcfg/README

+Gcfg reads INI-style configuration files into Go structs;
+supports user-defined types and subsections.
+
+Package docs: https://godoc.org/gopkg.in/gcfg.v1

source/vendor/github.com/go-git/gcfg/doc.go

+// Package gcfg reads "INI-style" text-based configuration files with
+// "name=value" pairs grouped into sections (gcfg files).
+//
+// This package is still a work in progress; see the sections below for planned
+// changes.
+//
+// Syntax
+//
+// The syntax is based on that used by git config:
+// http://git-scm.com/docs/git-config#_syntax .
+// There are some (planned) differences compared to the git config format:
+//  - improve data portability:
+//    - must be encoded in UTF-8 (for now) and must not contain the 0 byte
+//    - include and "path" type is not supported
+//      (path type may be implementable as a user-defined type)
+//  - internationalization
+//    - section and variable names can contain unicode letters, unicode digits
+//      (as defined in http://golang.org/ref/spec#Characters ) and hyphens
+//      (U+002D), starting with a unicode letter
+//  - disallow potentially ambiguous or misleading definitions:
+//    - `[sec.sub]` format is not allowed (deprecated in gitconfig)
+//    - `[sec ""]` is not allowed
+//      - use `[sec]` for section name "sec" and empty subsection name
+//    - (planned) within a single file, definitions must be contiguous for each:
+//      - section: '[secA]' -> '[secB]' -> '[secA]' is an error
+//      - subsection: '[sec "A"]' -> '[sec "B"]' -> '[sec "A"]' is an error
+//      - multivalued variable: 'multi=a' -> 'other=x' -> 'multi=b' is an error
+//
+// Data structure
+//
+// The functions in this package read values into a user-defined struct.
+// Each section corresponds to a struct field in the config struct, and each
+// variable in a section corresponds to a data field in the section struct.
+// The mapping of each section or variable name to fields is done either based
+// on the "gcfg" struct tag or by matching the name of the section or variable,
+// ignoring case. In the latter case, hyphens '-' in section and variable names
+// correspond to underscores '_' in field names.
+// Fields must be exported; to use a section or variable name starting with a
+// letter that is neither upper- or lower-case, prefix the field name with 'X'.
+// (See https://code.google.com/p/go/issues/detail?id=5763#c4 .)
+//
+// For sections with subsections, the corresponding field in config must be a
+// map, rather than a struct, with string keys and pointer-to-struct values.
+// Values for subsection variables are stored in the map with the subsection
+// name used as the map key.
+// (Note that unlike section and variable names, subsection names are case
+// sensitive.)
+// When using a map, and there is a section with the same section name but
+// without a subsection name, its values are stored with the empty string used
+// as the key.
+// It is possible to provide default values for subsections in the section
+// "default-<sectionname>" (or by setting values in the corresponding struct
+// field "Default_<sectionname>").
+//
+// The functions in this package panic if config is not a pointer to a struct,
+// or when a field is not of a suitable type (either a struct or a map with
+// string keys and pointer-to-struct values).
+//
+// Parsing of values
+//
+// The section structs in the config struct may contain single-valued or
+// multi-valued variables. Variables of unnamed slice type (that is, a type
+// starting with `[]`) are treated as multi-value; all others (including named
+// slice types) are treated as single-valued variables.
+//
+// Single-valued variables are handled based on the type as follows.
+// Unnamed pointer types (that is, types starting with `*`) are dereferenced,
+// and if necessary, a new instance is allocated.
+//
+// For types implementing the encoding.TextUnmarshaler interface, the
+// UnmarshalText method is used to set the value. Implementing this method is
+// the recommended way for parsing user-defined types.
+//
+// For fields of string kind, the value string is assigned to the field, after
+// unquoting and unescaping as needed.
+// For fields of bool kind, the field is set to true if the value is "true",
+// "yes", "on" or "1", and set to false if the value is "false", "no", "off" or
+// "0", ignoring case. In addition, single-valued bool fields can be specified
+// with a "blank" value (variable name without equals sign and value); in such
+// case the value is set to true.
+//
+// Predefined integer types [u]int(|8|16|32|64) and big.Int are parsed as
+// decimal or hexadecimal (if having '0x' prefix). (This is to prevent
+// unintuitively handling zero-padded numbers as octal.) Other types having
+// [u]int* as the underlying type, such as os.FileMode and uintptr allow
+// decimal, hexadecimal, or octal values.
+// Parsing mode for integer types can be overridden using the struct tag option
+// ",int=mode" where mode is a combination of the 'd', 'h', and 'o' characters
+// (each standing for decimal, hexadecimal, and octal, respectively.)
+//
+// All other types are parsed using fmt.Sscanf with the "%v" verb.
+//
+// For multi-valued variables, each individual value is parsed as above and
+// appended to the slice. If the first value is specified as a "blank" value
+// (variable name without equals sign and value), a new slice is allocated;
+// that is any values previously set in the slice will be ignored.
+//
+// The types subpackage for provides helpers for parsing "enum-like" and integer
+// types.
+//
+// Error handling
+//
+// There are 3 types of errors:
+//
+//  - programmer errors / panics:
+//    - invalid configuration structure
+//  - data errors:
+//    - fatal errors:
+//      - invalid configuration syntax
+//    - warnings:
+//      - data that doesn't belong to any part of the config structure
+//
+// Programmer errors trigger panics. These are should be fixed by the programmer
+// before releasing code that uses gcfg.
+//
+// Data errors cause gcfg to return a non-nil error value. This includes the
+// case when there are extra unknown key-value definitions in the configuration
+// data (extra data).
+// However, in some occasions it is desirable to be able to proceed in
+// situations when the only data error is that of extra data.
+// These errors are handled at a different (warning) priority and can be
+// filtered out programmatically. To ignore extra data warnings, wrap the
+// gcfg.Read*Into invocation into a call to gcfg.FatalOnly.
+//
+// TODO
+//
+// The following is a list of changes under consideration:
+//  - documentation
+//    - self-contained syntax documentation
+//    - more practical examples
+//    - move TODOs to issue tracker (eventually)
+//  - syntax
+//    - reconsider valid escape sequences
+//      (gitconfig doesn't support \r in value, \t in subsection name, etc.)
+//  - reading / parsing gcfg files
+//    - define internal representation structure
+//    - support multiple inputs (readers, strings, files)
+//    - support declaring encoding (?)
+//    - support varying fields sets for subsections (?)
+//  - writing gcfg files
+//  - error handling
+//    - make error context accessible programmatically?
+//    - limit input size?
+//
+package gcfg // import "github.com/go-git/gcfg"

source/vendor/github.com/go-git/gcfg/errors.go

+package gcfg
+
+import (
+	"gopkg.in/warnings.v0"
+)
+
+// FatalOnly filters the results of a Read*Into invocation and returns only
+// fatal errors. That is, errors (warnings) indicating data for unknown
+// sections / variables is ignored. Example invocation:
+//
+//  err := gcfg.FatalOnly(gcfg.ReadFileInto(&cfg, configFile))
+//  if err != nil {
+//      ...
+//
+func FatalOnly(err error) error {
+	return warnings.FatalOnly(err)
+}
+
+func isFatal(err error) bool {
+	_, ok := err.(extraData)
+	return !ok
+}
+
+type extraData struct {
+	section    string
+	subsection *string
+	variable   *string
+}
+
+func (e extraData) Error() string {
+	s := "can't store data at section \"" + e.section + "\""
+	if e.subsection != nil {
+		s += ", subsection \"" + *e.subsection + "\""
+	}
+	if e.variable != nil {
+		s += ", variable \"" + *e.variable + "\""
+	}
+	return s
+}
+
+var _ error = extraData{}

source/vendor/github.com/go-git/gcfg/read.go

+package gcfg
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"strings"
+
+	"gopkg.in/warnings.v0"
+
+	"github.com/go-git/gcfg/scanner"
+	"github.com/go-git/gcfg/token"
+)
+
+var unescape = map[rune]rune{'\\': '\\', '"': '"', 'n': '\n', 't': '\t', 'b': '\b', '\n': '\n'}
+
+// no error: invalid literals should be caught by scanner
+func unquote(s string) string {
+	u, q, esc := make([]rune, 0, len(s)), false, false
+	for _, c := range s {
+		if esc {
+			uc, ok := unescape[c]
+			switch {
+			case ok:
+				u = append(u, uc)
+				fallthrough
+			case !q && c == '\n':
+				esc = false
+				continue
+			}
+			panic("invalid escape sequence")
+		}
+		switch c {
+		case '"':
+			q = !q
+		case '\\':
+			esc = true
+		default:
+			u = append(u, c)
+		}
+	}
+	if q {
+		panic("missing end quote")
+	}
+	if esc {
+		panic("invalid escape sequence")
+	}
+	return string(u)
+}
+
+func read(c *warnings.Collector, callback func(string, string, string, string, bool) error,
+	fset *token.FileSet, file *token.File, src []byte) error {
+	//
+	var s scanner.Scanner
+	var errs scanner.ErrorList
+	s.Init(file, src, func(p token.Position, m string) { errs.Add(p, m) }, 0)
+	sect, sectsub := "", ""
+	pos, tok, lit := s.Scan()
+	errfn := func(msg string) error {
+		return fmt.Errorf("%s: %s", fset.Position(pos), msg)
+	}
+	for {
+		if errs.Len() > 0 {
+			if err := c.Collect(errs.Err()); err != nil {
+				return err
+			}
+		}
+		switch tok {
+		case token.EOF:
+			return nil
+		case token.EOL, token.COMMENT:
+			pos, tok, lit = s.Scan()
+		case token.LBRACK:
+			pos, tok, lit = s.Scan()
+			if errs.Len() > 0 {
+				if err := c.Collect(errs.Err()); err != nil {
+					return err
+				}
+			}
+			if tok != token.IDENT {
+				if err := c.Collect(errfn("expected section name")); err != nil {
+					return err
+				}
+			}
+			sect, sectsub = lit, ""
+			pos, tok, lit = s.Scan()
+			if errs.Len() > 0 {
+				if err := c.Collect(errs.Err()); err != nil {
+					return err
+				}
+			}
+			if tok == token.STRING {
+				sectsub = unquote(lit)
+				if sectsub == "" {
+					if err := c.Collect(errfn("empty subsection name")); err != nil {
+						return err
+					}
+				}
+				pos, tok, lit = s.Scan()
+				if errs.Len() > 0 {
+					if err := c.Collect(errs.Err()); err != nil {
+						return err
+					}
+				}
+			}
+			if tok != token.RBRACK {
+				if sectsub == "" {
+					if err := c.Collect(errfn("expected subsection name or right bracket")); err != nil {
+						return err
+					}
+				}
+				if err := c.Collect(errfn("expected right bracket")); err != nil {
+					return err
+				}
+			}
+			pos, tok, lit = s.Scan()
+			if tok != token.EOL && tok != token.EOF && tok != token.COMMENT {
+				if err := c.Collect(errfn("expected EOL, EOF, or comment")); err != nil {
+					return err
+				}
+			}
+			// If a section/subsection header was found, ensure a
+			// container object is created, even if there are no
+			// variables further down.
+			err := c.Collect(callback(sect, sectsub, "", "", true))
+			if err != nil {
+				return err
+			}
+		case token.IDENT:
+			if sect == "" {
+				if err := c.Collect(errfn("expected section header")); err != nil {
+					return err
+				}
+			}
+			n := lit
+			pos, tok, lit = s.Scan()
+			if errs.Len() > 0 {
+				return errs.Err()
+			}
+			blank, v := tok == token.EOF || tok == token.EOL || tok == token.COMMENT, ""
+			if !blank {
+				if tok != token.ASSIGN {
+					if err := c.Collect(errfn("expected '='")); err != nil {
+						return err
+					}
+				}
+				pos, tok, lit = s.Scan()
+				if errs.Len() > 0 {
+					if err := c.Collect(errs.Err()); err != nil {
+						return err
+					}
+				}
+				if tok != token.STRING {
+					if err := c.Collect(errfn("expected value")); err != nil {
+						return err
+					}
+				}
+				v = unquote(lit)
+				pos, tok, lit = s.Scan()
+				if errs.Len() > 0 {
+					if err := c.Collect(errs.Err()); err != nil {
+						return err
+					}
+				}
+				if tok != token.EOL && tok != token.EOF && tok != token.COMMENT {
+					if err := c.Collect(errfn("expected EOL, EOF, or comment")); err != nil {
+						return err
+					}
+				}
+			}
+			err := c.Collect(callback(sect, sectsub, n, v, blank))
+			if err != nil {
+				return err
+			}
+		default:
+			if sect == "" {
+				if err := c.Collect(errfn("expected section header")); err != nil {
+					return err
+				}
+			}
+			if err := c.Collect(errfn("expected section header or variable declaration")); err != nil {
+				return err
+			}
+		}
+	}
+	panic("never reached")
+}
+
+func readInto(config interface{}, fset *token.FileSet, file *token.File,
+	src []byte) error {
+	//
+	c := warnings.NewCollector(isFatal)
+	firstPassCallback := func(s string, ss string, k string, v string, bv bool) error {
+		return set(c, config, s, ss, k, v, bv, false)
+	}
+	err := read(c, firstPassCallback, fset, file, src)
+	if err != nil {
+		return err
+	}
+	secondPassCallback := func(s string, ss string, k string, v string, bv bool) error {
+		return set(c, config, s, ss, k, v, bv, true)
+	}
+	err = read(c, secondPassCallback, fset, file, src)
+	if err != nil {
+		return err
+	}
+	return c.Done()
+}
+
+// ReadWithCallback reads gcfg formatted data from reader and calls
+// callback with each section and option found.
+//
+// Callback is called with section, subsection, option key, option value
+// and blank value flag as arguments.
+//
+// When a section is found, callback is called with nil subsection, option key
+// and option value.
+//
+// When a subsection is found, callback is called with nil option key and
+// option value.
+//
+// If blank value flag is true, it means that the value was not set for an option
+// (as opposed to set to empty string).
+//
+// If callback returns an error, ReadWithCallback terminates with an error too.
+func ReadWithCallback(reader io.Reader, callback func(string, string, string, string, bool) error) error {
+	src, err := io.ReadAll(reader)
+	if err != nil {
+		return err
+	}
+
+	fset := token.NewFileSet()
+	file := fset.AddFile("", fset.Base(), len(src))
+	c := warnings.NewCollector(isFatal)
+
+	return read(c, callback, fset, file, src)
+}
+
+// ReadInto reads gcfg formatted data from reader and sets the values into the
+// corresponding fields in config.
+func ReadInto(config interface{}, reader io.Reader) error {
+	src, err := io.ReadAll(reader)
+	if err != nil {
+		return err
+	}
+	fset := token.NewFileSet()
+	file := fset.AddFile("", fset.Base(), len(src))
+	return readInto(config, fset, file, src)
+}
+
+// ReadStringInto reads gcfg formatted data from str and sets the values into
+// the corresponding fields in config.
+func ReadStringInto(config interface{}, str string) error {
+	r := strings.NewReader(str)
+	return ReadInto(config, r)
+}
+
+// ReadFileInto reads gcfg formatted data from the file filename and sets the
+// values into the corresponding fields in config.
+func ReadFileInto(config interface{}, filename string) error {
+	f, err := os.Open(filename)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	src, err := io.ReadAll(f)
+	if err != nil {
+		return err
+	}
+	fset := token.NewFileSet()
+	file := fset.AddFile(filename, fset.Base(), len(src))
+	return readInto(config, fset, file, src)
+}

source/vendor/github.com/go-git/gcfg/scanner/errors.go

+// 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.
+
+package scanner
+
+import (
+	"fmt"
+	"io"
+	"sort"
+)
+
+import (
+	"github.com/go-git/gcfg/token"
+)
+
+// In an ErrorList, an error is represented by an *Error.
+// The position Pos, if valid, points to the beginning of
+// the offending token, and the error condition is described
+// by Msg.
+//
+type Error struct {
+	Pos token.Position
+	Msg string
+}
+
+// Error implements the error interface.
+func (e Error) Error() string {
+	if e.Pos.Filename != "" || e.Pos.IsValid() {
+		// don't print "<unknown position>"
+		// TODO(gri) reconsider the semantics of Position.IsValid
+		return e.Pos.String() + ": " + e.Msg
+	}
+	return e.Msg
+}
+
+// ErrorList is a list of *Errors.
+// The zero value for an ErrorList is an empty ErrorList ready to use.
+//
+type ErrorList []*Error
+
+// Add adds an Error with given position and error message to an ErrorList.
+func (p *ErrorList) Add(pos token.Position, msg string) {
+	*p = append(*p, &Error{pos, msg})
+}
+
+// Reset resets an ErrorList to no errors.
+func (p *ErrorList) Reset() { *p = (*p)[0:0] }
+
+// ErrorList implements the sort Interface.
+func (p ErrorList) Len() int      { return len(p) }
+func (p ErrorList) Swap(i, j int) { p[i], p[j] = p[j], p[i] }
+
+func (p ErrorList) Less(i, j int) bool {
+	e := &p[i].Pos
+	f := &p[j].Pos
+	if e.Filename < f.Filename {
+		return true
+	}
+	if e.Filename == f.Filename {
+		return e.Offset < f.Offset
+	}
+	return false
+}
+
+// Sort sorts an ErrorList. *Error entries are sorted by position,
+// other errors are sorted by error message, and before any *Error
+// entry.
+//
+func (p ErrorList) Sort() {
+	sort.Sort(p)
+}
+
+// RemoveMultiples sorts an ErrorList and removes all but the first error per line.
+func (p *ErrorList) RemoveMultiples() {
+	sort.Sort(p)
+	var last token.Position // initial last.Line is != any legal error line
+	i := 0
+	for _, e := range *p {
+		if e.Pos.Filename != last.Filename || e.Pos.Line != last.Line {
+			last = e.Pos
+			(*p)[i] = e
+			i++
+		}
+	}
+	(*p) = (*p)[0:i]
+}
+
+// An ErrorList implements the error interface.
+func (p ErrorList) Error() string {
+	switch len(p) {
+	case 0:
+		return "no errors"
+	case 1:
+		return p[0].Error()
+	}
+	return fmt.Sprintf("%s (and %d more errors)", p[0], len(p)-1)
+}
+
+// Err returns an error equivalent to this error list.
+// If the list is empty, Err returns nil.
+func (p ErrorList) Err() error {
+	if len(p) == 0 {
+		return nil
+	}
+	return p
+}
+
+// PrintError is a utility function that prints a list of errors to w,
+// one error per line, if the err parameter is an ErrorList. Otherwise
+// it prints the err string.
+//
+func PrintError(w io.Writer, err error) {
+	if list, ok := err.(ErrorList); ok {
+		for _, e := range list {
+			fmt.Fprintf(w, "%s\n", e)
+		}
+	} else if err != nil {
+		fmt.Fprintf(w, "%s\n", err)
+	}
+}

source/vendor/github.com/go-git/gcfg/scanner/scanner.go

+// 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.
+
+// Package scanner implements a scanner for gcfg configuration text.
+// It takes a []byte as source which can then be tokenized
+// through repeated calls to the Scan method.
+//
+// Note that the API for the scanner package may change to accommodate new
+// features or implementation changes in gcfg.
+package scanner
+
+import (
+	"fmt"
+	"path/filepath"
+	"unicode"
+	"unicode/utf8"
+
+	"github.com/go-git/gcfg/token"
+)
+
+// An ErrorHandler may be provided to Scanner.Init. If a syntax error is
+// encountered and a handler was installed, the handler is called with a
+// position and an error message. The position points to the beginning of
+// the offending token.
+type ErrorHandler func(pos token.Position, msg string)
+
+// A Scanner holds the scanner's internal state while processing
+// a given text.  It can be allocated as part of another data
+// structure but must be initialized via Init before use.
+type Scanner struct {
+	// immutable state
+	file *token.File  // source file handle
+	dir  string       // directory portion of file.Name()
+	src  []byte       // source
+	err  ErrorHandler // error reporting; or nil
+	mode Mode         // scanning mode
+
+	// scanning state
+	ch         rune // current character
+	offset     int  // character offset
+	rdOffset   int  // reading offset (position after current character)
+	lineOffset int  // current line offset
+	nextVal    bool // next token is expected to be a value
+
+	// public state - ok to modify
+	ErrorCount int // number of errors encountered
+}
+
+// Read the next Unicode char into s.ch.
+// s.ch < 0 means end-of-file.
+func (s *Scanner) next() {
+	if s.rdOffset < len(s.src) {
+		s.offset = s.rdOffset
+		if s.ch == '\n' {
+			s.lineOffset = s.offset
+			s.file.AddLine(s.offset)
+		}
+		r, w := rune(s.src[s.rdOffset]), 1
+		switch {
+		case r == 0:
+			s.error(s.offset, "illegal character NUL")
+		case r >= 0x80:
+			// not ASCII
+			r, w = utf8.DecodeRune(s.src[s.rdOffset:])
+			if r == utf8.RuneError && w == 1 {
+				s.error(s.offset, "illegal UTF-8 encoding")
+			}
+		}
+		s.rdOffset += w
+		s.ch = r
+	} else {
+		s.offset = len(s.src)
+		if s.ch == '\n' {
+			s.lineOffset = s.offset
+			s.file.AddLine(s.offset)
+		}
+		s.ch = -1 // eof
+	}
+}
+
+// A mode value is a set of flags (or 0).
+// They control scanner behavior.
+type Mode uint
+
+const (
+	ScanComments Mode = 1 << iota // return comments as COMMENT tokens
+)
+
+// Init prepares the scanner s to tokenize the text src by setting the
+// scanner at the beginning of src. The scanner uses the file set file
+// for position information and it adds line information for each line.
+// It is ok to re-use the same file when re-scanning the same file as
+// line information which is already present is ignored. Init causes a
+// panic if the file size does not match the src size.
+//
+// Calls to Scan will invoke the error handler err if they encounter a
+// syntax error and err is not nil. Also, for each error encountered,
+// the Scanner field ErrorCount is incremented by one. The mode parameter
+// determines how comments are handled.
+//
+// Note that Init may call err if there is an error in the first character
+// of the file.
+func (s *Scanner) Init(file *token.File, src []byte, err ErrorHandler, mode Mode) {
+	// Explicitly initialize all fields since a scanner may be reused.
+	if file.Size() != len(src) {
+		panic(fmt.Sprintf("file size (%d) does not match src len (%d)", file.Size(), len(src)))
+	}
+	s.file = file
+	s.dir, _ = filepath.Split(file.Name())
+	s.src = src
+	s.err = err
+	s.mode = mode
+
+	s.ch = ' '
+	s.offset = 0
+	s.rdOffset = 0
+	s.lineOffset = 0
+	s.ErrorCount = 0
+	s.nextVal = false
+
+	s.next()
+}
+
+func (s *Scanner) error(offs int, msg string) {
+	if s.err != nil {
+		s.err(s.file.Position(s.file.Pos(offs)), msg)
+	}
+	s.ErrorCount++
+}
+
+func (s *Scanner) scanComment() string {
+	// initial [;#] already consumed
+	offs := s.offset - 1 // position of initial [;#]
+
+	for s.ch != '\n' && s.ch >= 0 {
+		s.next()
+	}
+	return string(s.src[offs:s.offset])
+}
+
+func isLetter(ch rune) bool {
+	return 'a' <= ch && ch <= 'z' || 'A' <= ch && ch <= 'Z' || ch >= 0x80 && unicode.IsLetter(ch)
+}
+
+func isDigit(ch rune) bool {
+	return '0' <= ch && ch <= '9' || ch >= 0x80 && unicode.IsDigit(ch)
+}
+
+func (s *Scanner) scanIdentifier() string {
+	offs := s.offset
+	for isLetter(s.ch) || isDigit(s.ch) || s.ch == '-' {
+		s.next()
+	}
+	return string(s.src[offs:s.offset])
+}
+
+// val indicate if we are scanning a value (vs a header)
+func (s *Scanner) scanEscape(val bool) {
+	offs := s.offset
+	ch := s.ch
+	s.next() // always make progress
+	switch ch {
+	case '\\', '"', '\n':
+		// ok
+	case 'n', 't', 'b':
+		if val {
+			break // ok
+		}
+		fallthrough
+	default:
+		s.error(offs, "unknown escape sequence")
+	}
+}
+
+func (s *Scanner) scanString() string {
+	// '"' opening already consumed
+	offs := s.offset - 1
+
+	for s.ch != '"' {
+		ch := s.ch
+		s.next()
+		if ch == '\n' || ch < 0 {
+			s.error(offs, "string not terminated")
+			break
+		}
+		if ch == '\\' {
+			s.scanEscape(false)
+		}
+	}
+
+	s.next()
+
+	return string(s.src[offs:s.offset])
+}
+
+func stripCR(b []byte) []byte {
+	c := make([]byte, len(b))
+	i := 0
+	for _, ch := range b {
+		if ch != '\r' {
+			c[i] = ch
+			i++
+		}
+	}
+	return c[:i]
+}
+
+func (s *Scanner) scanValString() string {
+	offs := s.offset
+
+	hasCR := false
+	end := offs
+	inQuote := false
+loop:
+	for inQuote || s.ch >= 0 && s.ch != '\n' && s.ch != ';' && s.ch != '#' {
+		ch := s.ch
+		s.next()
+		switch {
+		case inQuote && ch == '\\':
+			s.scanEscape(true)
+		case !inQuote && ch == '\\':
+			if s.ch == '\r' {
+				hasCR = true
+				s.next()
+			}
+			if s.ch != '\n' {
+				s.scanEscape(true)
+			} else {
+				s.next()
+			}
+		case ch == '"':
+			inQuote = !inQuote
+		case ch == '\r':
+			hasCR = true
+		case ch < 0 || inQuote && ch == '\n':
+			s.error(offs, "string not terminated")
+			break loop
+		}
+		if inQuote || !isWhiteSpace(ch) {
+			end = s.offset
+		}
+	}
+
+	lit := s.src[offs:end]
+	if hasCR {
+		lit = stripCR(lit)
+	}
+
+	return string(lit)
+}
+
+func isWhiteSpace(ch rune) bool {
+	return ch == ' ' || ch == '\t' || ch == '\r'
+}
+
+func (s *Scanner) skipWhitespace() {
+	for isWhiteSpace(s.ch) {
+		s.next()
+	}
+}
+
+// Scan scans the next token and returns the token position, the token,
+// and its literal string if applicable. The source end is indicated by
+// token.EOF.
+//
+// If the returned token is a literal (token.IDENT, token.STRING) or
+// token.COMMENT, the literal string has the corresponding value.
+//
+// If the returned token is token.ILLEGAL, the literal string is the
+// offending character.
+//
+// In all other cases, Scan returns an empty literal string.
+//
+// For more tolerant parsing, Scan will return a valid token if
+// possible even if a syntax error was encountered. Thus, even
+// if the resulting token sequence contains no illegal tokens,
+// a client may not assume that no error occurred. Instead it
+// must check the scanner's ErrorCount or the number of calls
+// of the error handler, if there was one installed.
+//
+// Scan adds line information to the file added to the file
+// set with Init. Token positions are relative to that file
+// and thus relative to the file set.
+func (s *Scanner) Scan() (pos token.Pos, tok token.Token, lit string) {
+scanAgain:
+	s.skipWhitespace()
+
+	// current token start
+	pos = s.file.Pos(s.offset)
+
+	// determine token value
+	switch ch := s.ch; {
+	case s.nextVal:
+		lit = s.scanValString()
+		tok = token.STRING
+		s.nextVal = false
+	case isLetter(ch):
+		lit = s.scanIdentifier()
+		tok = token.IDENT
+	default:
+		s.next() // always make progress
+		switch ch {
+		case -1:
+			tok = token.EOF
+		case '\n':
+			tok = token.EOL
+		case '"':
+			tok = token.STRING
+			lit = s.scanString()
+		case '[':
+			tok = token.LBRACK
+		case ']':
+			tok = token.RBRACK
+		case ';', '#':
+			// comment
+			lit = s.scanComment()
+			if s.mode&ScanComments == 0 {
+				// skip comment
+				goto scanAgain
+			}
+			tok = token.COMMENT
+		case '=':
+			tok = token.ASSIGN
+			s.nextVal = true
+		default:
+			s.error(s.file.Offset(pos), fmt.Sprintf("illegal character %#U", ch))
+			tok = token.ILLEGAL
+			lit = string(ch)
+		}
+	}
+
+	return
+}

source/vendor/github.com/go-git/gcfg/set.go

+package gcfg
+
+import (
+	"bytes"
+	"encoding"
+	"encoding/gob"
+	"fmt"
+	"math/big"
+	"reflect"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+
+	"gopkg.in/warnings.v0"
+
+	"github.com/go-git/gcfg/types"
+)
+
+type tag struct {
+	ident   string
+	intMode string
+}
+
+func newTag(ts string) tag {
+	t := tag{}
+	s := strings.Split(ts, ",")
+	t.ident = s[0]
+	for _, tse := range s[1:] {
+		if strings.HasPrefix(tse, "int=") {
+			t.intMode = tse[len("int="):]
+		}
+	}
+	return t
+}
+
+func fieldFold(v reflect.Value, name string) (reflect.Value, tag) {
+	var n string
+	r0, _ := utf8.DecodeRuneInString(name)
+	if unicode.IsLetter(r0) && !unicode.IsLower(r0) && !unicode.IsUpper(r0) {
+		n = "X"
+	}
+	n += strings.Replace(name, "-", "_", -1)
+	f, ok := v.Type().FieldByNameFunc(func(fieldName string) bool {
+		if !v.FieldByName(fieldName).CanSet() {
+			return false
+		}
+		f, _ := v.Type().FieldByName(fieldName)
+		t := newTag(f.Tag.Get("gcfg"))
+		if t.ident != "" {
+			return strings.EqualFold(t.ident, name)
+		}
+		return strings.EqualFold(n, fieldName)
+	})
+	if !ok {
+		return reflect.Value{}, tag{}
+	}
+	return v.FieldByName(f.Name), newTag(f.Tag.Get("gcfg"))
+}
+
+type setter func(destp interface{}, blank bool, val string, t tag) error
+
+var errUnsupportedType = fmt.Errorf("unsupported type")
+var errBlankUnsupported = fmt.Errorf("blank value not supported for type")
+
+var setters = []setter{
+	typeSetter, textUnmarshalerSetter, kindSetter, scanSetter,
+}
+
+func textUnmarshalerSetter(d interface{}, blank bool, val string, t tag) error {
+	dtu, ok := d.(encoding.TextUnmarshaler)
+	if !ok {
+		return errUnsupportedType
+	}
+	if blank {
+		return errBlankUnsupported
+	}
+	return dtu.UnmarshalText([]byte(val))
+}
+
+func boolSetter(d interface{}, blank bool, val string, t tag) error {
+	if blank {
+		reflect.ValueOf(d).Elem().Set(reflect.ValueOf(true))
+		return nil
+	}
+	b, err := types.ParseBool(val)
+	if err == nil {
+		reflect.ValueOf(d).Elem().Set(reflect.ValueOf(b))
+	}
+	return err
+}
+
+func intMode(mode string) types.IntMode {
+	var m types.IntMode
+	if strings.ContainsAny(mode, "dD") {
+		m |= types.Dec
+	}
+	if strings.ContainsAny(mode, "hH") {
+		m |= types.Hex
+	}
+	if strings.ContainsAny(mode, "oO") {
+		m |= types.Oct
+	}
+	return m
+}
+
+var typeModes = map[reflect.Type]types.IntMode{
+	reflect.TypeOf(int(0)):    types.Dec | types.Hex,
+	reflect.TypeOf(int8(0)):   types.Dec | types.Hex,
+	reflect.TypeOf(int16(0)):  types.Dec | types.Hex,
+	reflect.TypeOf(int32(0)):  types.Dec | types.Hex,
+	reflect.TypeOf(int64(0)):  types.Dec | types.Hex,
+	reflect.TypeOf(uint(0)):   types.Dec | types.Hex,
+	reflect.TypeOf(uint8(0)):  types.Dec | types.Hex,
+	reflect.TypeOf(uint16(0)): types.Dec | types.Hex,
+	reflect.TypeOf(uint32(0)): types.Dec | types.Hex,
+	reflect.TypeOf(uint64(0)): types.Dec | types.Hex,
+	// use default mode (allow dec/hex/oct) for uintptr type
+	reflect.TypeOf(big.Int{}): types.Dec | types.Hex,
+}
+
+func intModeDefault(t reflect.Type) types.IntMode {
+	m, ok := typeModes[t]
+	if !ok {
+		m = types.Dec | types.Hex | types.Oct
+	}
+	return m
+}
+
+func intSetter(d interface{}, blank bool, val string, t tag) error {
+	if blank {
+		return errBlankUnsupported
+	}
+	mode := intMode(t.intMode)
+	if mode == 0 {
+		mode = intModeDefault(reflect.TypeOf(d).Elem())
+	}
+	return types.ParseInt(d, val, mode)
+}
+
+func stringSetter(d interface{}, blank bool, val string, t tag) error {
+	if blank {
+		return errBlankUnsupported
+	}
+	dsp, ok := d.(*string)
+	if !ok {
+		return errUnsupportedType
+	}
+	*dsp = val
+	return nil
+}
+
+var kindSetters = map[reflect.Kind]setter{
+	reflect.String:  stringSetter,
+	reflect.Bool:    boolSetter,
+	reflect.Int:     intSetter,
+	reflect.Int8:    intSetter,
+	reflect.Int16:   intSetter,
+	reflect.Int32:   intSetter,
+	reflect.Int64:   intSetter,
+	reflect.Uint:    intSetter,
+	reflect.Uint8:   intSetter,
+	reflect.Uint16:  intSetter,
+	reflect.Uint32:  intSetter,
+	reflect.Uint64:  intSetter,
+	reflect.Uintptr: intSetter,
+}
+
+var typeSetters = map[reflect.Type]setter{
+	reflect.TypeOf(big.Int{}): intSetter,
+}
+
+func typeSetter(d interface{}, blank bool, val string, tt tag) error {
+	t := reflect.ValueOf(d).Type().Elem()
+	setter, ok := typeSetters[t]
+	if !ok {
+		return errUnsupportedType
+	}
+	return setter(d, blank, val, tt)
+}
+
+func kindSetter(d interface{}, blank bool, val string, tt tag) error {
+	k := reflect.ValueOf(d).Type().Elem().Kind()
+	setter, ok := kindSetters[k]
+	if !ok {
+		return errUnsupportedType
+	}
+	return setter(d, blank, val, tt)
+}
+
+func scanSetter(d interface{}, blank bool, val string, tt tag) error {
+	if blank {
+		return errBlankUnsupported
+	}
+	return types.ScanFully(d, val, 'v')
+}
+
+func newValue(c *warnings.Collector, sect string, vCfg reflect.Value,
+	vType reflect.Type) (reflect.Value, error) {
+	//
+	pv := reflect.New(vType)
+	dfltName := "default-" + sect
+	dfltField, _ := fieldFold(vCfg, dfltName)
+	var err error
+	if dfltField.IsValid() {
+		b := bytes.NewBuffer(nil)
+		ge := gob.NewEncoder(b)
+		if err = c.Collect(ge.EncodeValue(dfltField)); err != nil {
+			return pv, err
+		}
+		gd := gob.NewDecoder(bytes.NewReader(b.Bytes()))
+		if err = c.Collect(gd.DecodeValue(pv.Elem())); err != nil {
+			return pv, err
+		}
+	}
+	return pv, nil
+}
+
+func set(c *warnings.Collector, cfg interface{}, sect, sub, name string,
+	 value string, blankValue bool, subsectPass bool) error {
+	//
+	vPCfg := reflect.ValueOf(cfg)
+	if vPCfg.Kind() != reflect.Ptr || vPCfg.Elem().Kind() != reflect.Struct {
+		panic(fmt.Errorf("config must be a pointer to a struct"))
+	}
+	vCfg := vPCfg.Elem()
+	vSect, _ := fieldFold(vCfg, sect)
+	if !vSect.IsValid() {
+		err := extraData{section: sect}
+		return c.Collect(err)
+	}
+	isSubsect := vSect.Kind() == reflect.Map
+	if subsectPass != isSubsect {
+		return nil
+	}
+	if isSubsect {
+		vst := vSect.Type()
+		if vst.Key().Kind() != reflect.String ||
+			vst.Elem().Kind() != reflect.Ptr ||
+			vst.Elem().Elem().Kind() != reflect.Struct {
+			panic(fmt.Errorf("map field for section must have string keys and "+
+				" pointer-to-struct values: section %q", sect))
+		}
+		if vSect.IsNil() {
+			vSect.Set(reflect.MakeMap(vst))
+		}
+		k := reflect.ValueOf(sub)
+		pv := vSect.MapIndex(k)
+		if !pv.IsValid() {
+			vType := vSect.Type().Elem().Elem()
+			var err error
+			if pv, err = newValue(c, sect, vCfg, vType); err != nil {
+				return err
+			}
+			vSect.SetMapIndex(k, pv)
+		}
+		vSect = pv.Elem()
+	} else if vSect.Kind() != reflect.Struct {
+		panic(fmt.Errorf("field for section must be a map or a struct: "+
+			"section %q", sect))
+	} else if sub != "" {
+		err := extraData{section: sect, subsection: &sub}
+		return c.Collect(err)
+	}
+	// Empty name is a special value, meaning that only the
+	// section/subsection object is to be created, with no values set.
+	if name == "" {
+		return nil
+	}
+	vVar, t := fieldFold(vSect, name)
+	if !vVar.IsValid() {
+		var err error
+		if isSubsect {
+			err = extraData{section: sect, subsection: &sub, variable: &name}
+		} else {
+			err = extraData{section: sect, variable: &name}
+		}
+		return c.Collect(err)
+	}
+	// vVal is either single-valued var, or newly allocated value within multi-valued var
+	var vVal reflect.Value
+	// multi-value if unnamed slice type
+	isMulti := vVar.Type().Name() == "" && vVar.Kind() == reflect.Slice ||
+		vVar.Type().Name() == "" && vVar.Kind() == reflect.Ptr && vVar.Type().Elem().Name() == "" && vVar.Type().Elem().Kind() == reflect.Slice
+	if isMulti && vVar.Kind() == reflect.Ptr {
+		if vVar.IsNil() {
+			vVar.Set(reflect.New(vVar.Type().Elem()))
+		}
+		vVar = vVar.Elem()
+	}
+	if isMulti && blankValue {
+		vVar.Set(reflect.Zero(vVar.Type()))
+		return nil
+	}
+	if isMulti {
+		vVal = reflect.New(vVar.Type().Elem()).Elem()
+	} else {
+		vVal = vVar
+	}
+	isDeref := vVal.Type().Name() == "" && vVal.Type().Kind() == reflect.Ptr
+	isNew := isDeref && vVal.IsNil()
+	// vAddr is address of value to set (dereferenced & allocated as needed)
+	var vAddr reflect.Value
+	switch {
+	case isNew:
+		vAddr = reflect.New(vVal.Type().Elem())
+	case isDeref && !isNew:
+		vAddr = vVal
+	default:
+		vAddr = vVal.Addr()
+	}
+	vAddrI := vAddr.Interface()
+	err, ok := error(nil), false
+	for _, s := range setters {
+		err = s(vAddrI, blankValue, value, t)
+		if err == nil {
+			ok = true
+			break
+		}
+		if err != errUnsupportedType {
+			return err
+		}
+	}
+	if !ok {
+		// in case all setters returned errUnsupportedType
+		return err
+	}
+	if isNew { // set reference if it was dereferenced and newly allocated
+		vVal.Set(vAddr)
+	}
+	if isMulti { // append if multi-valued
+		vVar.Set(reflect.Append(vVar, vVal))
+	}
+	return nil
+}

source/vendor/github.com/go-git/gcfg/token/position.go

+// Copyright 2010 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.
+
+// TODO(gri) consider making this a separate package outside the go directory.
+
+package token
+
+import (
+	"fmt"
+	"sort"
+	"sync"
+)
+
+// -----------------------------------------------------------------------------
+// Positions
+
+// Position describes an arbitrary source position
+// including the file, line, and column location.
+// A Position is valid if the line number is > 0.
+//
+type Position struct {
+	Filename string // filename, if any
+	Offset   int    // offset, starting at 0
+	Line     int    // line number, starting at 1
+	Column   int    // column number, starting at 1 (character count)
+}
+
+// IsValid returns true if the position is valid.
+func (pos *Position) IsValid() bool { return pos.Line > 0 }
+
+// String returns a string in one of several forms:
+//
+//	file:line:column    valid position with file name
+//	line:column         valid position without file name
+//	file                invalid position with file name
+//	-                   invalid position without file name
+//
+func (pos Position) String() string {
+	s := pos.Filename
+	if pos.IsValid() {
+		if s != "" {
+			s += ":"
+		}
+		s += fmt.Sprintf("%d:%d", pos.Line, pos.Column)
+	}
+	if s == "" {
+		s = "-"
+	}
+	return s
+}
+
+// Pos is a compact encoding of a source position within a file set.
+// It can be converted into a Position for a more convenient, but much
+// larger, representation.
+//
+// The Pos value for a given file is a number in the range [base, base+size],
+// where base and size are specified when adding the file to the file set via
+// AddFile.
+//
+// To create the Pos value for a specific source offset, first add
+// the respective file to the current file set (via FileSet.AddFile)
+// and then call File.Pos(offset) for that file. Given a Pos value p
+// for a specific file set fset, the corresponding Position value is
+// obtained by calling fset.Position(p).
+//
+// Pos values can be compared directly with the usual comparison operators:
+// If two Pos values p and q are in the same file, comparing p and q is
+// equivalent to comparing the respective source file offsets. If p and q
+// are in different files, p < q is true if the file implied by p was added
+// to the respective file set before the file implied by q.
+//
+type Pos int
+
+// The zero value for Pos is NoPos; there is no file and line information
+// associated with it, and NoPos().IsValid() is false. NoPos is always
+// smaller than any other Pos value. The corresponding Position value
+// for NoPos is the zero value for Position.
+//
+const NoPos Pos = 0
+
+// IsValid returns true if the position is valid.
+func (p Pos) IsValid() bool {
+	return p != NoPos
+}
+
+// -----------------------------------------------------------------------------
+// File
+
+// A File is a handle for a file belonging to a FileSet.
+// A File has a name, size, and line offset table.
+//
+type File struct {
+	set  *FileSet
+	name string // file name as provided to AddFile
+	base int    // Pos value range for this file is [base...base+size]
+	size int    // file size as provided to AddFile
+
+	// lines and infos are protected by set.mutex
+	lines []int
+	infos []lineInfo
+}
+
+// Name returns the file name of file f as registered with AddFile.
+func (f *File) Name() string {
+	return f.name
+}
+
+// Base returns the base offset of file f as registered with AddFile.
+func (f *File) Base() int {
+	return f.base
+}
+
+// Size returns the size of file f as registered with AddFile.
+func (f *File) Size() int {
+	return f.size
+}
+
+// LineCount returns the number of lines in file f.
+func (f *File) LineCount() int {
+	f.set.mutex.RLock()
+	n := len(f.lines)
+	f.set.mutex.RUnlock()
+	return n
+}
+
+// AddLine adds the line offset for a new line.
+// The line offset must be larger than the offset for the previous line
+// and smaller than the file size; otherwise the line offset is ignored.
+//
+func (f *File) AddLine(offset int) {
+	f.set.mutex.Lock()
+	if i := len(f.lines); (i == 0 || f.lines[i-1] < offset) && offset < f.size {
+		f.lines = append(f.lines, offset)
+	}
+	f.set.mutex.Unlock()
+}
+
+// SetLines sets the line offsets for a file and returns true if successful.
+// The line offsets are the offsets of the first character of each line;
+// for instance for the content "ab\nc\n" the line offsets are {0, 3}.
+// An empty file has an empty line offset table.
+// Each line offset must be larger than the offset for the previous line
+// and smaller than the file size; otherwise SetLines fails and returns
+// false.
+//
+func (f *File) SetLines(lines []int) bool {
+	// verify validity of lines table
+	size := f.size
+	for i, offset := range lines {
+		if i > 0 && offset <= lines[i-1] || size <= offset {
+			return false
+		}
+	}
+
+	// set lines table
+	f.set.mutex.Lock()
+	f.lines = lines
+	f.set.mutex.Unlock()
+	return true
+}
+
+// SetLinesForContent sets the line offsets for the given file content.
+func (f *File) SetLinesForContent(content []byte) {
+	var lines []int
+	line := 0
+	for offset, b := range content {
+		if line >= 0 {
+			lines = append(lines, line)
+		}
+		line = -1
+		if b == '\n' {
+			line = offset + 1
+		}
+	}
+
+	// set lines table
+	f.set.mutex.Lock()
+	f.lines = lines
+	f.set.mutex.Unlock()
+}
+
+// A lineInfo object describes alternative file and line number
+// information (such as provided via a //line comment in a .go
+// file) for a given file offset.
+type lineInfo struct {
+	// fields are exported to make them accessible to gob
+	Offset   int
+	Filename string
+	Line     int
+}
+
+// AddLineInfo adds alternative file and line number information for
+// a given file offset. The offset must be larger than the offset for
+// the previously added alternative line info and smaller than the
+// file size; otherwise the information is ignored.
+//
+// AddLineInfo is typically used to register alternative position
+// information for //line filename:line comments in source files.
+//
+func (f *File) AddLineInfo(offset int, filename string, line int) {
+	f.set.mutex.Lock()
+	if i := len(f.infos); i == 0 || f.infos[i-1].Offset < offset && offset < f.size {
+		f.infos = append(f.infos, lineInfo{offset, filename, line})
+	}
+	f.set.mutex.Unlock()
+}
+
+// Pos returns the Pos value for the given file offset;
+// the offset must be <= f.Size().
+// f.Pos(f.Offset(p)) == p.
+//
+func (f *File) Pos(offset int) Pos {
+	if offset > f.size {
+		panic("illegal file offset")
+	}
+	return Pos(f.base + offset)
+}
+
+// Offset returns the offset for the given file position p;
+// p must be a valid Pos value in that file.
+// f.Offset(f.Pos(offset)) == offset.
+//
+func (f *File) Offset(p Pos) int {
+	if int(p) < f.base || int(p) > f.base+f.size {
+		panic("illegal Pos value")
+	}
+	return int(p) - f.base
+}
+
+// Line returns the line number for the given file position p;
+// p must be a Pos value in that file or NoPos.
+//
+func (f *File) Line(p Pos) int {
+	// TODO(gri) this can be implemented much more efficiently
+	return f.Position(p).Line
+}
+
+func searchLineInfos(a []lineInfo, x int) int {
+	return sort.Search(len(a), func(i int) bool { return a[i].Offset > x }) - 1
+}
+
+// info returns the file name, line, and column number for a file offset.
+func (f *File) info(offset int) (filename string, line, column int) {
+	filename = f.name
+	if i := searchInts(f.lines, offset); i >= 0 {
+		line, column = i+1, offset-f.lines[i]+1
+	}
+	if len(f.infos) > 0 {
+		// almost no files have extra line infos
+		if i := searchLineInfos(f.infos, offset); i >= 0 {
+			alt := &f.infos[i]
+			filename = alt.Filename
+			if i := searchInts(f.lines, alt.Offset); i >= 0 {
+				line += alt.Line - i - 1
+			}
+		}
+	}
+	return
+}
+
+func (f *File) position(p Pos) (pos Position) {
+	offset := int(p) - f.base
+	pos.Offset = offset
+	pos.Filename, pos.Line, pos.Column = f.info(offset)
+	return
+}
+
+// Position returns the Position value for the given file position p;
+// p must be a Pos value in that file or NoPos.
+//
+func (f *File) Position(p Pos) (pos Position) {
+	if p != NoPos {
+		if int(p) < f.base || int(p) > f.base+f.size {
+			panic("illegal Pos value")
+		}
+		pos = f.position(p)
+	}
+	return
+}
+
+// -----------------------------------------------------------------------------
+// FileSet
+
+// A FileSet represents a set of source files.
+// Methods of file sets are synchronized; multiple goroutines
+// may invoke them concurrently.
+//
+type FileSet struct {
+	mutex sync.RWMutex // protects the file set
+	base  int          // base offset for the next file
+	files []*File      // list of files in the order added to the set
+	last  *File        // cache of last file looked up
+}
+
+// NewFileSet creates a new file set.
+func NewFileSet() *FileSet {
+	s := new(FileSet)
+	s.base = 1 // 0 == NoPos
+	return s
+}
+
+// Base returns the minimum base offset that must be provided to
+// AddFile when adding the next file.
+//
+func (s *FileSet) Base() int {
+	s.mutex.RLock()
+	b := s.base
+	s.mutex.RUnlock()
+	return b
+
+}
+
+// AddFile adds a new file with a given filename, base offset, and file size
+// to the file set s and returns the file. Multiple files may have the same
+// name. The base offset must not be smaller than the FileSet's Base(), and
+// size must not be negative.
+//
+// Adding the file will set the file set's Base() value to base + size + 1
+// as the minimum base value for the next file. The following relationship
+// exists between a Pos value p for a given file offset offs:
+//
+//	int(p) = base + offs
+//
+// with offs in the range [0, size] and thus p in the range [base, base+size].
+// For convenience, File.Pos may be used to create file-specific position
+// values from a file offset.
+//
+func (s *FileSet) AddFile(filename string, base, size int) *File {
+	s.mutex.Lock()
+	defer s.mutex.Unlock()
+	if base < s.base || size < 0 {
+		panic("illegal base or size")
+	}
+	// base >= s.base && size >= 0
+	f := &File{s, filename, base, size, []int{0}, nil}
+	base += size + 1 // +1 because EOF also has a position
+	if base < 0 {
+		panic("token.Pos offset overflow (> 2G of source code in file set)")
+	}
+	// add the file to the file set
+	s.base = base
+	s.files = append(s.files, f)
+	s.last = f
+	return f
+}
+
+// Iterate calls f for the files in the file set in the order they were added
+// until f returns false.
+//
+func (s *FileSet) Iterate(f func(*File) bool) {
+	for i := 0; ; i++ {
+		var file *File
+		s.mutex.RLock()
+		if i < len(s.files) {
+			file = s.files[i]
+		}
+		s.mutex.RUnlock()
+		if file == nil || !f(file) {
+			break
+		}
+	}
+}
+
+func searchFiles(a []*File, x int) int {
+	return sort.Search(len(a), func(i int) bool { return a[i].base > x }) - 1
+}
+
+func (s *FileSet) file(p Pos) *File {
+	// common case: p is in last file
+	if f := s.last; f != nil && f.base <= int(p) && int(p) <= f.base+f.size {
+		return f
+	}
+	// p is not in last file - search all files
+	if i := searchFiles(s.files, int(p)); i >= 0 {
+		f := s.files[i]
+		// f.base <= int(p) by definition of searchFiles
+		if int(p) <= f.base+f.size {
+			s.last = f
+			return f
+		}
+	}
+	return nil
+}
+
+// File returns the file that contains the position p.
+// If no such file is found (for instance for p == NoPos),
+// the result is nil.
+//
+func (s *FileSet) File(p Pos) (f *File) {
+	if p != NoPos {
+		s.mutex.RLock()
+		f = s.file(p)
+		s.mutex.RUnlock()
+	}
+	return
+}
+
+// Position converts a Pos in the fileset into a general Position.
+func (s *FileSet) Position(p Pos) (pos Position) {
+	if p != NoPos {
+		s.mutex.RLock()
+		if f := s.file(p); f != nil {
+			pos = f.position(p)
+		}
+		s.mutex.RUnlock()
+	}
+	return
+}
+
+// -----------------------------------------------------------------------------
+// Helper functions
+
+func searchInts(a []int, x int) int {
+	// This function body is a manually inlined version of:
+	//
+	//   return sort.Search(len(a), func(i int) bool { return a[i] > x }) - 1
+	//
+	// With better compiler optimizations, this may not be needed in the
+	// future, but at the moment this change improves the go/printer
+	// benchmark performance by ~30%. This has a direct impact on the
+	// speed of gofmt and thus seems worthwhile (2011-04-29).
+	// TODO(gri): Remove this when compilers have caught up.
+	i, j := 0, len(a)
+	for i < j {
+		h := i + (j-i)/2 // avoid overflow when computing h
+		// i ≤ h < j
+		if a[h] <= x {
+			i = h + 1
+		} else {
+			j = h
+		}
+	}
+	return i - 1
+}

source/vendor/github.com/go-git/gcfg/token/serialize.go

+// Copyright 2011 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.
+
+package token
+
+type serializedFile struct {
+	// fields correspond 1:1 to fields with same (lower-case) name in File
+	Name  string
+	Base  int
+	Size  int
+	Lines []int
+	Infos []lineInfo
+}
+
+type serializedFileSet struct {
+	Base  int
+	Files []serializedFile
+}
+
+// Read calls decode to deserialize a file set into s; s must not be nil.
+func (s *FileSet) Read(decode func(interface{}) error) error {
+	var ss serializedFileSet
+	if err := decode(&ss); err != nil {
+		return err
+	}
+
+	s.mutex.Lock()
+	s.base = ss.Base
+	files := make([]*File, len(ss.Files))
+	for i := 0; i < len(ss.Files); i++ {
+		f := &ss.Files[i]
+		files[i] = &File{s, f.Name, f.Base, f.Size, f.Lines, f.Infos}
+	}
+	s.files = files
+	s.last = nil
+	s.mutex.Unlock()
+
+	return nil
+}
+
+// Write calls encode to serialize the file set s.
+func (s *FileSet) Write(encode func(interface{}) error) error {
+	var ss serializedFileSet
+
+	s.mutex.Lock()
+	ss.Base = s.base
+	files := make([]serializedFile, len(s.files))
+	for i, f := range s.files {
+		files[i] = serializedFile{f.name, f.base, f.size, f.lines, f.infos}
+	}
+	ss.Files = files
+	s.mutex.Unlock()
+
+	return encode(ss)
+}