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-rw-r--r--vendor/github.com/google/go-intervals/LICENSE202
-rw-r--r--vendor/github.com/google/go-intervals/intervalset/intervalset.go545
-rw-r--r--vendor/github.com/google/go-intervals/intervalset/intervalset_immutable.go85
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diff --git a/vendor/github.com/google/go-intervals/LICENSE b/vendor/github.com/google/go-intervals/LICENSE
new file mode 100644
index 000000000..d64569567
--- /dev/null
+++ b/vendor/github.com/google/go-intervals/LICENSE
@@ -0,0 +1,202 @@
+
+ Apache License
+ Version 2.0, January 2004
+ http://www.apache.org/licenses/
+
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diff --git a/vendor/github.com/google/go-intervals/intervalset/intervalset.go b/vendor/github.com/google/go-intervals/intervalset/intervalset.go
new file mode 100644
index 000000000..6a33db63c
--- /dev/null
+++ b/vendor/github.com/google/go-intervals/intervalset/intervalset.go
@@ -0,0 +1,545 @@
+// Copyright 2017 Google Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package intervalset provides an abtraction for dealing with sets of
+// 1-dimensional spans, such as sets of time ranges. The Set type provides set
+// arithmetic and enumeration methods based on an Interval interface.
+//
+// DISCLAIMER: This library is not yet stable, so expect breaking changes.
+package intervalset
+
+import (
+ "fmt"
+ "sort"
+ "strings"
+)
+
+// Interval is the interface for a continuous or discrete span. The interval is
+// assumed to be inclusive of the starting point and exclusive of the ending
+// point.
+//
+// All methods in the interface are non-destructive: Calls to the methods should
+// not modify the interval. Furthermore, the implementation assumes an interval
+// will not be mutated by user code, either.
+type Interval interface {
+ // Intersect returns the intersection of an interval with another
+ // interval. The function may panic if the other interval is incompatible.
+ Intersect(Interval) Interval
+
+ // Before returns true if the interval is completely before another interval.
+ Before(Interval) bool
+
+ // IsZero returns true for the zero value of an interval.
+ IsZero() bool
+
+ // Bisect returns two intervals, one on the lower side of x and one on the
+ // upper side of x, corresponding to the subtraction of x from the original
+ // interval. The returned intervals are always within the range of the
+ // original interval.
+ Bisect(x Interval) (Interval, Interval)
+
+ // Adjoin returns the union of two intervals, if the intervals are exactly
+ // adjacent, or the zero interval if they are not.
+ Adjoin(Interval) Interval
+
+ // Encompass returns an interval that covers the exact extents of two
+ // intervals.
+ Encompass(Interval) Interval
+}
+
+// Set is a set of interval objects used for
+type Set struct {
+ //non-overlapping intervals
+ intervals []Interval
+ // factory is needed when the extents of the empty set are needed.
+ factory intervalFactory
+}
+
+// SetInput is an interface implemented by Set and ImmutableSet. It is used when
+// one of these types type must take a set as an argument.
+type SetInput interface {
+ // Extent returns the Interval defined by the minimum and maximum values of
+ // the set.
+ Extent() Interval
+
+ // IntervalsBetween iterates over the intervals within extents set and calls f
+ // with each. If f returns false, iteration ceases.
+ //
+ // Any interval within the set that overlaps partially with extents is truncated
+ // before being passed to f.
+ IntervalsBetween(extents Interval, f IntervalReceiver)
+}
+
+// NewSet returns a new set given a sorted slice of intervals. This function
+// panics if the intervals are not sorted.
+func NewSet(intervals []Interval) *Set {
+ return NewSetV1(intervals, oldBehaviorFactory.makeZero)
+}
+
+// NewSetV1 returns a new set given a sorted slice of intervals. This function
+// panics if the intervals are not sorted.
+//
+// NewSetV1 will be renamed and will replace NewSet in the v1 release.
+func NewSetV1(intervals []Interval, makeZero func() Interval) *Set {
+ if err := CheckSorted(intervals); err != nil {
+ panic(err)
+ }
+ return &Set{intervals, makeIntervalFactor(makeZero)}
+}
+
+// CheckSorted checks that interval[i+1] is not before interval[i] for all
+// relevant elements of the input slice. Nil is returned when len(intervals) is
+// 0 or 1.
+func CheckSorted(intervals []Interval) error {
+ for i := 0; i < len(intervals)-1; i++ {
+ if !intervals[i].Before(intervals[i+1]) {
+ return fmt.Errorf("!intervals[%d].Before(intervals[%d]) for %s, %s", i, i+1, intervals[i], intervals[i+1])
+ }
+ }
+ return nil
+}
+
+// Empty returns a new, empty set of intervals.
+func Empty() *Set {
+ return EmptyV1(oldBehaviorFactory.makeZero)
+}
+
+// EmptyV1 returns a new, empty set of intervals using the semantics of the V1
+// API, which will require a factory method for construction of an empty interval.
+func EmptyV1(makeZero func() Interval) *Set {
+ return &Set{nil, makeIntervalFactor(makeZero)}
+}
+
+// Copy returns a copy of a set that may be mutated without affecting the original.
+func (s *Set) Copy() *Set {
+ return &Set{append([]Interval(nil), s.intervals...), s.factory}
+}
+
+// String returns a human-friendly representation of the set.
+func (s *Set) String() string {
+ var strs []string
+ for _, x := range s.intervals {
+ strs = append(strs, fmt.Sprintf("%s", x))
+ }
+ return fmt.Sprintf("{%s}", strings.Join(strs, ", "))
+}
+
+// Extent returns the Interval defined by the minimum and maximum values of the
+// set.
+func (s *Set) Extent() Interval {
+ if len(s.intervals) == 0 {
+ return s.factory.makeZero()
+ }
+ return s.intervals[0].Encompass(s.intervals[len(s.intervals)-1])
+}
+
+// Add adds all the elements of another set to this set.
+func (s *Set) Add(b SetInput) {
+ // Deal with nil extent. See https://github.com/google/go-intervals/issues/6.
+ bExtent := b.Extent()
+ if bExtent == nil {
+ return // no changes needed
+ }
+
+ // Loop through the intervals of x
+ b.IntervalsBetween(bExtent, func(x Interval) bool {
+ s.insert(x)
+ return true
+ })
+}
+
+// Contains reports whether an interval is entirely contained by the set.
+func (s *Set) Contains(ival Interval) bool {
+ // Loop through the intervals of x
+ next := s.iterator(ival, true)
+ for setInterval := next(); setInterval != nil; setInterval = next() {
+ left, right := ival.Bisect(setInterval)
+ if !left.IsZero() {
+ return false
+ }
+ ival = right
+ }
+ return ival.IsZero()
+}
+
+// adjoinOrAppend adds an interval to the end of intervals unless that value
+// directly adjoins the last element of intervals, in which case the last
+// element will be replaced by the adjoined interval.
+func adjoinOrAppend(intervals []Interval, x Interval) []Interval {
+ lastIndex := len(intervals) - 1
+ if lastIndex == -1 {
+ return append(intervals, x)
+ }
+ adjoined := intervals[lastIndex].Adjoin(x)
+ if adjoined.IsZero() {
+ return append(intervals, x)
+ }
+ intervals[lastIndex] = adjoined
+ return intervals
+}
+
+func (s *Set) insert(insertion Interval) {
+ if s.Contains(insertion) {
+ return
+ }
+ // TODO(reddaly): Something like Java's ArrayList would allow both O(log(n))
+ // insertion and O(log(n)) lookup. For now, we have O(log(n)) lookup and O(n)
+ // insertion.
+ var newIntervals []Interval
+ push := func(x Interval) {
+ newIntervals = adjoinOrAppend(newIntervals, x)
+ }
+ inserted := false
+ for _, x := range s.intervals {
+ if inserted {
+ push(x)
+ continue
+ }
+ if insertion.Before(x) {
+ push(insertion)
+ push(x)
+ inserted = true
+ continue
+ }
+ // [===left===)[==x===)[===right===)
+ left, right := insertion.Bisect(x)
+ if !left.IsZero() {
+ push(left)
+ }
+ push(x)
+ // Replace the interval being inserted with the remaining portion of the
+ // interval to be inserted.
+ if right.IsZero() {
+ inserted = true
+ } else {
+ insertion = right
+ }
+ }
+ if !inserted {
+ push(insertion)
+ }
+ s.intervals = newIntervals
+}
+
+// Sub destructively modifies the set by subtracting b.
+func (s *Set) Sub(b SetInput) {
+ extent := s.Extent()
+ // Deal with nil extent. See https://github.com/google/go-intervals/issues/6.
+ if extent == nil {
+ // Set is already empty, no changes necessary.
+ return
+ }
+ var newIntervals []Interval
+ push := func(x Interval) {
+ newIntervals = adjoinOrAppend(newIntervals, x)
+ }
+ nextX := s.iterator(extent, true)
+ nextY, cancel := setIntervalIterator(b, extent)
+ defer cancel()
+
+ x := nextX()
+ y := nextY()
+ for x != nil {
+ // If y == nil, all of the remaining intervals in A are to the right of B,
+ // so just yield them.
+ if y == nil {
+ push(x)
+ x = nextX()
+ continue
+ }
+ // Split x into parts left and right of y.
+ // The diagrams below show the bisection results for various situations.
+ // if left.IsZero() && !right.IsZero()
+ // xxx
+ // y1y1 y2y2 y3 y4y4
+ // xxx
+ // or
+ // xxxxxxxxxxxx
+ // y1y1 y2y2 y3 y4y4
+ //
+ // if !left.IsZero() && !right.IsZero()
+ // x1x1x1x1x1
+ // y1 y2
+ //
+ // if left.IsZero() && right.IsZero()
+ // x1x1x1x1 x2x2x2
+ // y1y1y1y1y1y1y1
+ //
+ // if !left.IsZero() && right.IsZero()
+ // x1x1 x2
+ // y1y1y1y1
+ left, right := x.Bisect(y)
+
+ // If the left side of x is non-zero, it can definitely be pushed to the
+ // resulting interval set since no subsequent y value will intersect it.
+ // The sequences look something like
+ // x1x1x1x1x1 OR x1x1x1 x2
+ // y1 y2 y1y1y1
+ // left = x1x1 x1x1x1
+ // right = x1x1 {zero}
+ if !left.IsZero() {
+ push(left)
+ }
+
+ if !right.IsZero() {
+ // If the right side of x is non-zero:
+ // 1) Right is the remaining portion of x that needs to be pushed.
+ x = right
+ // 2) It's not possible for current y to intersect it, so advance y. It's
+ // possible nextY() will intersect it, so don't push yet.
+ y = nextY()
+ } else {
+ // There's nothing left of x to push, so advance x.
+ x = nextX()
+ }
+ }
+
+ // Setting s.intervals is the only side effect in this function.
+ s.intervals = newIntervals
+}
+
+// intersectionIterator returns a function that yields intervals that are
+// members of the intersection of s and b, in increasing order.
+func (s *Set) intersectionIterator(b SetInput) (iter func() Interval, cancel func()) {
+ return intervalMapperToIterator(func(f IntervalReceiver) {
+ sExtent, bExtent := s.Extent(), b.Extent()
+ // Deal with nil extent. See https://github.com/google/go-intervals/issues/6.
+ if sExtent == nil || bExtent == nil {
+ // IF either set is already empty, the intersection is empty. This
+ // voids a panic below where a valid Interval is needed for each
+ // extent.
+ return
+ }
+ nextX := s.iterator(bExtent, true)
+ nextY, cancel := setIntervalIterator(b, sExtent)
+ defer cancel()
+
+ x := nextX()
+ y := nextY()
+ // Loop through corresponding intervals of S and B.
+ // If y == nil, all of the remaining intervals in S are to the right of B.
+ // If x == nil, all of the remaining intervals in B are to the right of S.
+ for x != nil && y != nil {
+ if x.Before(y) {
+ x = nextX()
+ continue
+ }
+ if y.Before(x) {
+ y = nextY()
+ continue
+ }
+ xyIntersect := x.Intersect(y)
+ if !xyIntersect.IsZero() {
+ if !f(xyIntersect) {
+ return
+ }
+ _, right := x.Bisect(y)
+ if !right.IsZero() {
+ x = right
+ } else {
+ x = nextX()
+ }
+ }
+ }
+ })
+}
+
+// Intersect destructively modifies the set by intersectin it with b.
+func (s *Set) Intersect(b SetInput) {
+ iter, cancel := s.intersectionIterator(b)
+ defer cancel()
+ var newIntervals []Interval
+ for x := iter(); x != nil; x = iter() {
+ newIntervals = append(newIntervals, x)
+ }
+ s.intervals = newIntervals
+}
+
+// searchLow returns the first index in s.intervals that is not before x.
+func (s *Set) searchLow(x Interval) int {
+ return sort.Search(len(s.intervals), func(i int) bool {
+ return !s.intervals[i].Before(x)
+ })
+}
+
+// searchLow returns the index of the first interval in s.intervals that is
+// entirely after x.
+func (s *Set) searchHigh(x Interval) int {
+ return sort.Search(len(s.intervals), func(i int) bool {
+ return x.Before(s.intervals[i])
+ })
+}
+
+// iterator returns a function that yields elements of the set in order.
+//
+// The function returned will return nil when finished iterating.
+func (s *Set) iterator(extents Interval, forward bool) func() Interval {
+ low, high := s.searchLow(extents), s.searchHigh(extents)
+
+ i, stride := low, 1
+ if !forward {
+ i, stride = high-1, -1
+ }
+
+ return func() Interval {
+ if i < 0 || i >= len(s.intervals) {
+ return nil
+ }
+ x := s.intervals[i]
+ i += stride
+ return x
+ }
+}
+
+// IntervalReceiver is a function used for iterating over a set of intervals. It
+// takes the start and end times and returns true if the iteration should
+// continue.
+type IntervalReceiver func(Interval) bool
+
+// IntervalsBetween iterates over the intervals within extents set and calls f
+// with each. If f returns false, iteration ceases.
+//
+// Any interval within the set that overlaps partially with extents is truncated
+// before being passed to f.
+func (s *Set) IntervalsBetween(extents Interval, f IntervalReceiver) {
+ // Begin = first index in s.intervals that is not before extents.
+ begin := sort.Search(len(s.intervals), func(i int) bool {
+ return !s.intervals[i].Before(extents)
+ })
+
+ // TODO(reddaly): Optimize this by performing a binary search for the ending
+ // point.
+ for _, interval := range s.intervals[begin:] {
+ // If the interval is after the extents, there will be no more overlap, so
+ // break out of the loop.
+ if extents.Before(interval) {
+ break
+ }
+ portionOfInterval := extents.Intersect(interval)
+ if portionOfInterval.IsZero() {
+ continue
+ }
+
+ if !f(portionOfInterval) {
+ return
+ }
+ }
+}
+
+// Intervals iterates over all the intervals within the set and calls f with
+// each one. If f returns false, iteration ceases.
+func (s *Set) Intervals(f IntervalReceiver) {
+ for _, interval := range s.intervals {
+ if !f(interval) {
+ return
+ }
+ }
+}
+
+// AllIntervals returns an ordered slice of all the intervals in the set.
+func (s *Set) AllIntervals() []Interval {
+ return append(make([]Interval, 0, len(s.intervals)), s.intervals...)
+}
+
+// ImmutableSet returns an immutable copy of this set.
+func (s *Set) ImmutableSet() *ImmutableSet {
+ return NewImmutableSet(s.AllIntervals())
+}
+
+// mapFn reports true if an iteration should continue. It is called on values of
+// a collection.
+type mapFn func(interface{}) bool
+
+// mapFn calls mapFn for each member of a collection.
+type mapperFn func(mapFn)
+
+// iteratorFn returns the next item in an iteration or the zero value. The
+// second return value indicates whether the first return value is a member of
+// the collection.
+type iteratorFn func() (interface{}, bool)
+
+// generatorFn returns an iterator.
+type generatorFn func() iteratorFn
+
+// cancelFn should be called to clean up the goroutine that would otherwise leak.
+type cancelFn func()
+
+// mapperToIterator returns an iteratorFn version of a mappingFn. The second
+// return value must be called at the end of iteration, or the underlying
+// goroutine will leak.
+func mapperToIterator(m mapperFn) (iteratorFn, cancelFn) {
+ generatedValues := make(chan interface{}, 1)
+ stopCh := make(chan interface{}, 1)
+ go func() {
+ m(func(obj interface{}) bool {
+ select {
+ case <-stopCh:
+ return false
+ case generatedValues <- obj:
+ return true
+ }
+ })
+ close(generatedValues)
+ }()
+ iter := func() (interface{}, bool) {
+ value, ok := <-generatedValues
+ return value, ok
+ }
+ return iter, func() {
+ stopCh <- nil
+ }
+}
+
+func intervalMapperToIterator(mapper func(IntervalReceiver)) (iter func() Interval, cancel func()) {
+ genericMapper := func(m mapFn) {
+ mapper(func(ival Interval) bool {
+ return m(ival)
+ })
+ }
+
+ genericIter, cancel := mapperToIterator(genericMapper)
+ return func() Interval {
+ genericVal, iterationEnded := genericIter()
+ if !iterationEnded {
+ return nil
+ }
+ ival, ok := genericVal.(Interval)
+ if !ok {
+ panic("unexpected value type, internal error")
+ }
+ return ival
+ }, cancel
+}
+
+func setIntervalIterator(s SetInput, extent Interval) (iter func() Interval, cancel func()) {
+ return intervalMapperToIterator(func(f IntervalReceiver) {
+ s.IntervalsBetween(extent, f)
+ })
+}
+
+// oldBehaviorFactory returns a nil interval. This was used before
+// construction of a Set/ImmutableSet required passing in a factory method for
+// creating a zero interval object.
+var oldBehaviorFactory = makeIntervalFactor(func() Interval { return nil })
+
+// intervalFactory is used to construct a zero-value interval. The zero value
+// interval may be different for different types of intervals, so a factory is
+// sometimes needed to write generic algorithms about intervals.
+type intervalFactory struct {
+ makeZero func() Interval
+}
+
+func makeIntervalFactor(makeZero func() Interval) intervalFactory {
+ return intervalFactory{makeZero}
+}
diff --git a/vendor/github.com/google/go-intervals/intervalset/intervalset_immutable.go b/vendor/github.com/google/go-intervals/intervalset/intervalset_immutable.go
new file mode 100644
index 000000000..f6d5cbb52
--- /dev/null
+++ b/vendor/github.com/google/go-intervals/intervalset/intervalset_immutable.go
@@ -0,0 +1,85 @@
+// Copyright 2017 Google Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package intervalset
+
+// ImmutableSet is a set of interval objects. It provides various set theory
+// operations.
+type ImmutableSet struct {
+ set *Set
+}
+
+// NewImmutableSet returns a new set given a sorted slice of intervals. This
+// function panics if the intervals are not sorted.
+func NewImmutableSet(intervals []Interval) *ImmutableSet {
+ return NewImmutableSetV1(intervals, oldBehaviorFactory.makeZero)
+}
+
+// NewImmutableSetV1 returns a new set given a sorted slice of intervals. This
+// function panics if the intervals are not sorted.
+func NewImmutableSetV1(intervals []Interval, makeZero func() Interval) *ImmutableSet {
+ return &ImmutableSet{NewSetV1(intervals, makeZero)}
+}
+
+// String returns a human-friendly representation of the set.
+func (s *ImmutableSet) String() string {
+ return s.set.String()
+}
+
+// Extent returns the Interval defined by the minimum and maximum values of the
+// set.
+func (s *ImmutableSet) Extent() Interval {
+ return s.set.Extent()
+}
+
+// Contains reports whether an interval is entirely contained by the set.
+func (s *ImmutableSet) Contains(ival Interval) bool {
+ return s.set.Contains(ival)
+}
+
+// Union returns a set with the contents of this set and another set.
+func (s *ImmutableSet) Union(b SetInput) *ImmutableSet {
+ union := s.set.Copy()
+ union.Add(b)
+ return &ImmutableSet{union}
+}
+
+// Sub returns a set without the intervals of another set.
+func (s *ImmutableSet) Sub(b SetInput) *ImmutableSet {
+ x := s.set.Copy()
+ x.Sub(b)
+ return &ImmutableSet{x}
+}
+
+// Intersect returns the intersection of two sets.
+func (s *ImmutableSet) Intersect(b SetInput) *ImmutableSet {
+ x := s.set.Copy()
+ x.Intersect(b)
+ return &ImmutableSet{x}
+}
+
+// IntervalsBetween iterates over the intervals within extents set and calls f
+// with each. If f returns false, iteration ceases.
+//
+// Any interval within the set that overlaps partially with extents is truncated
+// before being passed to f.
+func (s *ImmutableSet) IntervalsBetween(extents Interval, f IntervalReceiver) {
+ s.set.IntervalsBetween(extents, f)
+}
+
+// Intervals iterates over all the intervals within the set and calls f with
+// each one. If f returns false, iteration ceases.
+func (s *ImmutableSet) Intervals(f IntervalReceiver) {
+ s.set.Intervals(f)
+}