all: switch out defunct set library to different one (#16873)

* keystore, ethash, eth, miner, rpc, whisperv6: tech debt with now defunct set.

* whisperv5: swap out gopkg.in/fatih/set.v0 with supported set

25 files changed, 1069 insertions, 843 deletions

diff --git a/AUTHORS b/AUTHORS
index bd44a3de5..609dc48c7 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -171,3 +171,4 @@ xiekeyang <xiekeyang@users.noreply.github.com>
 yoza <yoza.is12s@gmail.com>
 ΞTHΞЯSPHΞЯΞ <{viktor.tron,nagydani,zsfelfoldi}@gmail.com>
 Максим Чусовлянов <mchusovlianov@gmail.com>
+Ralph Caraveo <deckarep@gmail.com>
diff --git a/accounts/keystore/account_cache.go b/accounts/keystore/account_cache.go
index 71f698ece..da3a46eb8 100644
--- a/accounts/keystore/account_cache.go
+++ b/accounts/keystore/account_cache.go
@@ -27,10 +27,10 @@ import (
 	"sync"
 	"time"
 
+	mapset "github.com/deckarep/golang-set"
 	"github.com/ethereum/go-ethereum/accounts"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/log"
-	"gopkg.in/fatih/set.v0"
 )
 
 // Minimum amount of time between cache reloads. This limit applies if the platform does
@@ -79,7 +79,7 @@ func newAccountCache(keydir string) (*accountCache, chan struct{}) {
 		keydir: keydir,
 		byAddr: make(map[common.Address][]accounts.Account),
 		notify: make(chan struct{}, 1),
-		fileC:  fileCache{all: set.NewNonTS()},
+		fileC:  fileCache{all: mapset.NewThreadUnsafeSet()},
 	}
 	ac.watcher = newWatcher(ac)
 	return ac, ac.notify
@@ -237,7 +237,7 @@ func (ac *accountCache) scanAccounts() error {
 		log.Debug("Failed to reload keystore contents", "err", err)
 		return err
 	}
-	if creates.Size() == 0 && deletes.Size() == 0 && updates.Size() == 0 {
+	if creates.Cardinality() == 0 && deletes.Cardinality() == 0 && updates.Cardinality() == 0 {
 		return nil
 	}
 	// Create a helper method to scan the contents of the key files
@@ -272,15 +272,15 @@ func (ac *accountCache) scanAccounts() error {
 	// Process all the file diffs
 	start := time.Now()
 
-	for _, p := range creates.List() {
+	for _, p := range creates.ToSlice() {
 		if a := readAccount(p.(string)); a != nil {
 			ac.add(*a)
 		}
 	}
-	for _, p := range deletes.List() {
+	for _, p := range deletes.ToSlice() {
 		ac.deleteByFile(p.(string))
 	}
-	for _, p := range updates.List() {
+	for _, p := range updates.ToSlice() {
 		path := p.(string)
 		ac.deleteByFile(path)
 		if a := readAccount(path); a != nil {
diff --git a/accounts/keystore/file_cache.go b/accounts/keystore/file_cache.go
index c91b7b7b6..26da34dcf 100644
--- a/accounts/keystore/file_cache.go
+++ b/accounts/keystore/file_cache.go
@@ -24,20 +24,20 @@ import (
 	"sync"
 	"time"
 
+	mapset "github.com/deckarep/golang-set"
 	"github.com/ethereum/go-ethereum/log"
-	set "gopkg.in/fatih/set.v0"
 )
 
 // fileCache is a cache of files seen during scan of keystore.
 type fileCache struct {
-	all     *set.SetNonTS // Set of all files from the keystore folder
-	lastMod time.Time     // Last time instance when a file was modified
+	all     mapset.Set // Set of all files from the keystore folder
+	lastMod time.Time  // Last time instance when a file was modified
 	mu      sync.RWMutex
 }
 
 // scan performs a new scan on the given directory, compares against the already
 // cached filenames, and returns file sets: creates, deletes, updates.
-func (fc *fileCache) scan(keyDir string) (set.Interface, set.Interface, set.Interface, error) {
+func (fc *fileCache) scan(keyDir string) (mapset.Set, mapset.Set, mapset.Set, error) {
 	t0 := time.Now()
 
 	// List all the failes from the keystore folder
@@ -51,8 +51,8 @@ func (fc *fileCache) scan(keyDir string) (set.Interface, set.Interface, set.Inte
 	defer fc.mu.Unlock()
 
 	// Iterate all the files and gather their metadata
-	all := set.NewNonTS()
-	mods := set.NewNonTS()
+	all := mapset.NewThreadUnsafeSet()
+	mods := mapset.NewThreadUnsafeSet()
 
 	var newLastMod time.Time
 	for _, fi := range files {
@@ -76,9 +76,9 @@ func (fc *fileCache) scan(keyDir string) (set.Interface, set.Interface, set.Inte
 	t2 := time.Now()
 
 	// Update the tracked files and return the three sets
-	deletes := set.Difference(fc.all, all)   // Deletes = previous - current
-	creates := set.Difference(all, fc.all)   // Creates = current - previous
-	updates := set.Difference(mods, creates) // Updates = modified - creates
+	deletes := fc.all.Difference(all)   // Deletes = previous - current
+	creates := all.Difference(fc.all)   // Creates = current - previous
+	updates := mods.Difference(creates) // Updates = modified - creates
 
 	fc.all, fc.lastMod = all, newLastMod
 	t3 := time.Now()
diff --git a/consensus/ethash/consensus.go b/consensus/ethash/consensus.go
index bc97dbca4..eb0f73d98 100644
--- a/consensus/ethash/consensus.go
+++ b/consensus/ethash/consensus.go
@@ -24,6 +24,7 @@ import (
 	"runtime"
 	"time"
 
+	mapset "github.com/deckarep/golang-set"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/math"
 	"github.com/ethereum/go-ethereum/consensus"
@@ -31,7 +32,6 @@ import (
 	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/params"
-	set "gopkg.in/fatih/set.v0"
 )
 
 // Ethash proof-of-work protocol constants.
@@ -177,7 +177,7 @@ func (ethash *Ethash) VerifyUncles(chain consensus.ChainReader, block *types.Blo
 		return errTooManyUncles
 	}
 	// Gather the set of past uncles and ancestors
-	uncles, ancestors := set.New(), make(map[common.Hash]*types.Header)
+	uncles, ancestors := mapset.NewSet(), make(map[common.Hash]*types.Header)
 
 	number, parent := block.NumberU64()-1, block.ParentHash()
 	for i := 0; i < 7; i++ {
@@ -198,7 +198,7 @@ func (ethash *Ethash) VerifyUncles(chain consensus.ChainReader, block *types.Blo
 	for _, uncle := range block.Uncles() {
 		// Make sure every uncle is rewarded only once
 		hash := uncle.Hash()
-		if uncles.Has(hash) {
+		if uncles.Contains(hash) {
 			return errDuplicateUncle
 		}
 		uncles.Add(hash)
diff --git a/eth/peer.go b/eth/peer.go
index 953aca17b..b5f450855 100644
--- a/eth/peer.go
+++ b/eth/peer.go
@@ -23,11 +23,11 @@ import (
 	"sync"
 	"time"
 
+	mapset "github.com/deckarep/golang-set"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/p2p"
 	"github.com/ethereum/go-ethereum/rlp"
-	"gopkg.in/fatih/set.v0"
 )
 
 var (
@@ -85,8 +85,8 @@ type peer struct {
 	td   *big.Int
 	lock sync.RWMutex
 
-	knownTxs    *set.Set                  // Set of transaction hashes known to be known by this peer
-	knownBlocks *set.Set                  // Set of block hashes known to be known by this peer
+	knownTxs    mapset.Set                // Set of transaction hashes known to be known by this peer
+	knownBlocks mapset.Set                // Set of block hashes known to be known by this peer
 	queuedTxs   chan []*types.Transaction // Queue of transactions to broadcast to the peer
 	queuedProps chan *propEvent           // Queue of blocks to broadcast to the peer
 	queuedAnns  chan *types.Block         // Queue of blocks to announce to the peer
@@ -99,8 +99,8 @@ func newPeer(version int, p *p2p.Peer, rw p2p.MsgReadWriter) *peer {
 		rw:          rw,
 		version:     version,
 		id:          fmt.Sprintf("%x", p.ID().Bytes()[:8]),
-		knownTxs:    set.New(),
-		knownBlocks: set.New(),
+		knownTxs:    mapset.NewSet(),
+		knownBlocks: mapset.NewSet(),
 		queuedTxs:   make(chan []*types.Transaction, maxQueuedTxs),
 		queuedProps: make(chan *propEvent, maxQueuedProps),
 		queuedAnns:  make(chan *types.Block, maxQueuedAnns),
@@ -177,7 +177,7 @@ func (p *peer) SetHead(hash common.Hash, td *big.Int) {
 // never be propagated to this particular peer.
 func (p *peer) MarkBlock(hash common.Hash) {
 	// If we reached the memory allowance, drop a previously known block hash
-	for p.knownBlocks.Size() >= maxKnownBlocks {
+	for p.knownBlocks.Cardinality() >= maxKnownBlocks {
 		p.knownBlocks.Pop()
 	}
 	p.knownBlocks.Add(hash)
@@ -187,7 +187,7 @@ func (p *peer) MarkBlock(hash common.Hash) {
 // will never be propagated to this particular peer.
 func (p *peer) MarkTransaction(hash common.Hash) {
 	// If we reached the memory allowance, drop a previously known transaction hash
-	for p.knownTxs.Size() >= maxKnownTxs {
+	for p.knownTxs.Cardinality() >= maxKnownTxs {
 		p.knownTxs.Pop()
 	}
 	p.knownTxs.Add(hash)
@@ -470,7 +470,7 @@ func (ps *peerSet) PeersWithoutBlock(hash common.Hash) []*peer {
 
 	list := make([]*peer, 0, len(ps.peers))
 	for _, p := range ps.peers {
-		if !p.knownBlocks.Has(hash) {
+		if !p.knownBlocks.Contains(hash) {
 			list = append(list, p)
 		}
 	}
@@ -485,7 +485,7 @@ func (ps *peerSet) PeersWithoutTx(hash common.Hash) []*peer {
 
 	list := make([]*peer, 0, len(ps.peers))
 	for _, p := range ps.peers {
-		if !p.knownTxs.Has(hash) {
+		if !p.knownTxs.Contains(hash) {
 			list = append(list, p)
 		}
 	}
diff --git a/miner/worker.go b/miner/worker.go
index ff48ecabc..e4e42f877 100644
--- a/miner/worker.go
+++ b/miner/worker.go
@@ -24,6 +24,7 @@ import (
 	"sync/atomic"
 	"time"
 
+	mapset "github.com/deckarep/golang-set"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/consensus"
 	"github.com/ethereum/go-ethereum/consensus/misc"
@@ -35,7 +36,6 @@ import (
 	"github.com/ethereum/go-ethereum/event"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/params"
-	"gopkg.in/fatih/set.v0"
 )
 
 const (
@@ -67,9 +67,9 @@ type Work struct {
 	signer types.Signer
 
 	state     *state.StateDB // apply state changes here
-	ancestors *set.Set       // ancestor set (used for checking uncle parent validity)
-	family    *set.Set       // family set (used for checking uncle invalidity)
-	uncles    *set.Set       // uncle set
+	ancestors mapset.Set     // ancestor set (used for checking uncle parent validity)
+	family    mapset.Set     // family set (used for checking uncle invalidity)
+	uncles    mapset.Set     // uncle set
 	tcount    int            // tx count in cycle
 	gasPool   *core.GasPool  // available gas used to pack transactions
 
@@ -362,9 +362,9 @@ func (self *worker) makeCurrent(parent *types.Block, header *types.Header) error
 		config:    self.config,
 		signer:    types.NewEIP155Signer(self.config.ChainID),
 		state:     state,
-		ancestors: set.New(),
-		family:    set.New(),
-		uncles:    set.New(),
+		ancestors: mapset.NewSet(),
+		family:    mapset.NewSet(),
+		uncles:    mapset.NewSet(),
 		header:    header,
 		createdAt: time.Now(),
 	}
@@ -492,13 +492,13 @@ func (self *worker) commitNewWork() {
 
 func (self *worker) commitUncle(work *Work, uncle *types.Header) error {
 	hash := uncle.Hash()
-	if work.uncles.Has(hash) {
+	if work.uncles.Contains(hash) {
 		return fmt.Errorf("uncle not unique")
 	}
-	if !work.ancestors.Has(uncle.ParentHash) {
+	if !work.ancestors.Contains(uncle.ParentHash) {
 		return fmt.Errorf("uncle's parent unknown (%x)", uncle.ParentHash[0:4])
 	}
-	if work.family.Has(hash) {
+	if work.family.Contains(hash) {
 		return fmt.Errorf("uncle already in family (%x)", hash)
 	}
 	work.uncles.Add(uncle.Hash())
diff --git a/rpc/server.go b/rpc/server.go
index 8925419fe..90ffadd25 100644
--- a/rpc/server.go
+++ b/rpc/server.go
@@ -25,8 +25,8 @@ import (
 	"sync"
 	"sync/atomic"
 
+	mapset "github.com/deckarep/golang-set"
 	"github.com/ethereum/go-ethereum/log"
-	"gopkg.in/fatih/set.v0"
 )
 
 const MetadataApi = "rpc"
@@ -46,7 +46,7 @@ const (
 func NewServer() *Server {
 	server := &Server{
 		services: make(serviceRegistry),
-		codecs:   set.New(),
+		codecs:   mapset.NewSet(),
 		run:      1,
 	}
 
diff --git a/rpc/types.go b/rpc/types.go
index f2375604e..4252c3602 100644
--- a/rpc/types.go
+++ b/rpc/types.go
@@ -23,8 +23,8 @@ import (
 	"strings"
 	"sync"
 
+	mapset "github.com/deckarep/golang-set"
 	"github.com/ethereum/go-ethereum/common/hexutil"
-	"gopkg.in/fatih/set.v0"
 )
 
 // API describes the set of methods offered over the RPC interface
@@ -73,7 +73,7 @@ type Server struct {
 
 	run      int32
 	codecsMu sync.Mutex
-	codecs   *set.Set
+	codecs   mapset.Set
 }
 
 // rpcRequest represents a raw incoming RPC request
diff --git a/rpc/websocket.go b/rpc/websocket.go
index a6e1cec28..e7a86ddae 100644
--- a/rpc/websocket.go
+++ b/rpc/websocket.go
@@ -29,9 +29,9 @@ import (
 	"strings"
 	"time"
 
+	mapset "github.com/deckarep/golang-set"
 	"github.com/ethereum/go-ethereum/log"
 	"golang.org/x/net/websocket"
-	"gopkg.in/fatih/set.v0"
 )
 
 // websocketJSONCodec is a custom JSON codec with payload size enforcement and
@@ -84,7 +84,7 @@ func NewWSServer(allowedOrigins []string, srv *Server) *http.Server {
 // websocket upgrade process. When a '*' is specified as an allowed origins all
 // connections are accepted.
 func wsHandshakeValidator(allowedOrigins []string) func(*websocket.Config, *http.Request) error {
-	origins := set.New()
+	origins := mapset.NewSet()
 	allowAllOrigins := false
 
 	for _, origin := range allowedOrigins {
@@ -97,18 +97,18 @@ func wsHandshakeValidator(allowedOrigins []string) func(*websocket.Config, *http
 	}
 
 	// allow localhost if no allowedOrigins are specified.
-	if len(origins.List()) == 0 {
+	if len(origins.ToSlice()) == 0 {
 		origins.Add("http://localhost")
 		if hostname, err := os.Hostname(); err == nil {
 			origins.Add("http://" + strings.ToLower(hostname))
 		}
 	}
 
-	log.Debug(fmt.Sprintf("Allowed origin(s) for WS RPC interface %v\n", origins.List()))
+	log.Debug(fmt.Sprintf("Allowed origin(s) for WS RPC interface %v\n", origins.ToSlice()))
 
 	f := func(cfg *websocket.Config, req *http.Request) error {
 		origin := strings.ToLower(req.Header.Get("Origin"))
-		if allowAllOrigins || origins.Has(origin) {
+		if allowAllOrigins || origins.Contains(origin) {
 			return nil
 		}
 		log.Warn(fmt.Sprintf("origin '%s' not allowed on WS-RPC interface\n", origin))
diff --git a/vendor/gopkg.in/fatih/set.v0/LICENSE.md b/vendor/github.com/deckarep/golang-set/LICENSE
index 25fdaf639..b5768f89c 100644
--- a/vendor/gopkg.in/fatih/set.v0/LICENSE.md
+++ b/vendor/github.com/deckarep/golang-set/LICENSE
@@ -1,20 +1,22 @@
-The MIT License (MIT)
+Open Source Initiative OSI - The MIT License (MIT):Licensing
 
-Copyright (c) 2013 Fatih Arslan
+The MIT License (MIT)
+Copyright (c) 2013 Ralph Caraveo (deckarep@gmail.com)
 
 Permission is hereby granted, free of charge, to any person obtaining a copy of
 this software and associated documentation files (the "Software"), to deal in
 the Software without restriction, including without limitation the rights to
-use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
-the Software, and to permit persons to whom the Software is furnished to do so,
-subject to the following conditions:
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
 
 The above copyright notice and this permission notice shall be included in all
 copies or substantial portions of the Software.
 
 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
-FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
-COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
-IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
-CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
\ No newline at end of file
diff --git a/vendor/github.com/deckarep/golang-set/README.md b/vendor/github.com/deckarep/golang-set/README.md
new file mode 100644
index 000000000..c3b50b2c5
--- /dev/null
+++ b/vendor/github.com/deckarep/golang-set/README.md
@@ -0,0 +1,95 @@
+[![Build Status](https://travis-ci.org/deckarep/golang-set.svg?branch=master)](https://travis-ci.org/deckarep/golang-set)
+[![Go Report Card](https://goreportcard.com/badge/github.com/deckarep/golang-set)](https://goreportcard.com/report/github.com/deckarep/golang-set)
+[![GoDoc](https://godoc.org/github.com/deckarep/golang-set?status.svg)](http://godoc.org/github.com/deckarep/golang-set)
+
+## golang-set
+
+
+The missing set collection for the Go language.  Until Go has sets built-in...use this.
+
+Coming from Python one of the things I miss is the superbly wonderful set collection.  This is my attempt to mimic the primary features of the set from Python.
+You can of course argue that there is no need for a set in Go, otherwise the creators would have added one to the standard library.  To those I say simply ignore this repository
+and carry-on and to the rest that find this useful please contribute in helping me make it better by:
+
+* Helping to make more idiomatic improvements to the code.
+* Helping to increase the performance of it. ~~(So far, no attempt has been made, but since it uses a map internally, I expect it to be mostly performant.)~~
+* Helping to make the unit-tests more robust and kick-ass.
+* Helping to fill in the [documentation.](http://godoc.org/github.com/deckarep/golang-set)
+* Simply offering feedback and suggestions.  (Positive, constructive feedback is appreciated.)
+
+I have to give some credit for helping seed the idea with this post on [stackoverflow.](http://programmers.stackexchange.com/questions/177428/sets-data-structure-in-golang)
+
+*Update* - as of 3/9/2014, you can use a compile-time generic version of this package in the [gen](http://clipperhouse.github.io/gen/) framework.  This framework allows you to use the golang-set in a completely generic and type-safe way by allowing you to generate a supporting .go file based on your custom types.
+
+## Features (as of 9/22/2014)
+
+* a CartesianProduct() method has been added with unit-tests: [Read more about the cartesian product](http://en.wikipedia.org/wiki/Cartesian_product)
+
+## Features (as of 9/15/2014)
+
+* a PowerSet() method has been added with unit-tests: [Read more about the Power set](http://en.wikipedia.org/wiki/Power_set)
+
+## Features (as of 4/22/2014)
+
+* One common interface to both implementations
+* Two set implementations to choose from
+  * a thread-safe implementation designed for concurrent use
+  * a non-thread-safe implementation designed for performance
+* 75 benchmarks for both implementations
+* 35 unit tests for both implementations
+* 14 concurrent tests for the thread-safe implementation
+
+
+
+Please see the unit test file for additional usage examples.  The Python set documentation will also do a better job than I can of explaining how a set typically [works.](http://docs.python.org/2/library/sets.html)    Please keep in mind
+however that the Python set is a built-in type and supports additional features and syntax that make it awesome.
+
+## Examples but not exhaustive:
+
+```go
+requiredClasses := mapset.NewSet()
+requiredClasses.Add("Cooking")
+requiredClasses.Add("English")
+requiredClasses.Add("Math")
+requiredClasses.Add("Biology")
+
+scienceSlice := []interface{}{"Biology", "Chemistry"}
+scienceClasses := mapset.NewSetFromSlice(scienceSlice)
+
+electiveClasses := mapset.NewSet()
+electiveClasses.Add("Welding")
+electiveClasses.Add("Music")
+electiveClasses.Add("Automotive")
+
+bonusClasses := mapset.NewSet()
+bonusClasses.Add("Go Programming")
+bonusClasses.Add("Python Programming")
+
+//Show me all the available classes I can take
+allClasses := requiredClasses.Union(scienceClasses).Union(electiveClasses).Union(bonusClasses)
+fmt.Println(allClasses) //Set{Cooking, English, Math, Chemistry, Welding, Biology, Music, Automotive, Go Programming, Python Programming}
+
+
+//Is cooking considered a science class?
+fmt.Println(scienceClasses.Contains("Cooking")) //false
+
+//Show me all classes that are not science classes, since I hate science.
+fmt.Println(allClasses.Difference(scienceClasses)) //Set{Music, Automotive, Go Programming, Python Programming, Cooking, English, Math, Welding}
+
+//Which science classes are also required classes?
+fmt.Println(scienceClasses.Intersect(requiredClasses)) //Set{Biology}
+
+//How many bonus classes do you offer?
+fmt.Println(bonusClasses.Cardinality()) //2
+
+//Do you have the following classes? Welding, Automotive and English?
+fmt.Println(allClasses.IsSuperset(mapset.NewSetFromSlice([]interface{}{"Welding", "Automotive", "English"}))) //true
+```
+
+Thanks!
+
+-Ralph
+
+[![Bitdeli Badge](https://d2weczhvl823v0.cloudfront.net/deckarep/golang-set/trend.png)](https://bitdeli.com/free "Bitdeli Badge")
+
+[![Analytics](https://ga-beacon.appspot.com/UA-42584447-2/deckarep/golang-set)](https://github.com/igrigorik/ga-beacon)
diff --git a/vendor/github.com/deckarep/golang-set/iterator.go b/vendor/github.com/deckarep/golang-set/iterator.go
new file mode 100644
index 000000000..9dfecade4
--- /dev/null
+++ b/vendor/github.com/deckarep/golang-set/iterator.go
@@ -0,0 +1,58 @@
+/*
+Open Source Initiative OSI - The MIT License (MIT):Licensing
+
+The MIT License (MIT)
+Copyright (c) 2013 Ralph Caraveo (deckarep@gmail.com)
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+*/
+
+package mapset
+
+// Iterator defines an iterator over a Set, its C channel can be used to range over the Set's
+// elements.
+type Iterator struct {
+	C    <-chan interface{}
+	stop chan struct{}
+}
+
+// Stop stops the Iterator, no further elements will be received on C, C will be closed.
+func (i *Iterator) Stop() {
+	// Allows for Stop() to be called multiple times
+	// (close() panics when called on already closed channel)
+	defer func() {
+		recover()
+	}()
+
+	close(i.stop)
+
+	// Exhaust any remaining elements.
+	for range i.C {
+	}
+}
+
+// newIterator returns a new Iterator instance together with its item and stop channels.
+func newIterator() (*Iterator, chan<- interface{}, <-chan struct{}) {
+	itemChan := make(chan interface{})
+	stopChan := make(chan struct{})
+	return &Iterator{
+		C:    itemChan,
+		stop: stopChan,
+	}, itemChan, stopChan
+}
diff --git a/vendor/github.com/deckarep/golang-set/set.go b/vendor/github.com/deckarep/golang-set/set.go
new file mode 100644
index 000000000..29eb2e5a2
--- /dev/null
+++ b/vendor/github.com/deckarep/golang-set/set.go
@@ -0,0 +1,217 @@
+/*
+Open Source Initiative OSI - The MIT License (MIT):Licensing
+
+The MIT License (MIT)
+Copyright (c) 2013 Ralph Caraveo (deckarep@gmail.com)
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+*/
+
+// Package mapset implements a simple and generic set collection.
+// Items stored within it are unordered and unique. It supports
+// typical set operations: membership testing, intersection, union,
+// difference, symmetric difference and cloning.
+//
+// Package mapset provides two implementations of the Set
+// interface. The default implementation is safe for concurrent
+// access, but a non-thread-safe implementation is also provided for
+// programs that can benefit from the slight speed improvement and
+// that can enforce mutual exclusion through other means.
+package mapset
+
+// Set is the primary interface provided by the mapset package.  It
+// represents an unordered set of data and a large number of
+// operations that can be applied to that set.
+type Set interface {
+	// Adds an element to the set. Returns whether
+	// the item was added.
+	Add(i interface{}) bool
+
+	// Returns the number of elements in the set.
+	Cardinality() int
+
+	// Removes all elements from the set, leaving
+	// the empty set.
+	Clear()
+
+	// Returns a clone of the set using the same
+	// implementation, duplicating all keys.
+	Clone() Set
+
+	// Returns whether the given items
+	// are all in the set.
+	Contains(i ...interface{}) bool
+
+	// Returns the difference between this set
+	// and other. The returned set will contain
+	// all elements of this set that are not also
+	// elements of other.
+	//
+	// Note that the argument to Difference
+	// must be of the same type as the receiver
+	// of the method. Otherwise, Difference will
+	// panic.
+	Difference(other Set) Set
+
+	// Determines if two sets are equal to each
+	// other. If they have the same cardinality
+	// and contain the same elements, they are
+	// considered equal. The order in which
+	// the elements were added is irrelevant.
+	//
+	// Note that the argument to Equal must be
+	// of the same type as the receiver of the
+	// method. Otherwise, Equal will panic.
+	Equal(other Set) bool
+
+	// Returns a new set containing only the elements
+	// that exist only in both sets.
+	//
+	// Note that the argument to Intersect
+	// must be of the same type as the receiver
+	// of the method. Otherwise, Intersect will
+	// panic.
+	Intersect(other Set) Set
+
+	// Determines if every element in this set is in
+	// the other set but the two sets are not equal.
+	//
+	// Note that the argument to IsProperSubset
+	// must be of the same type as the receiver
+	// of the method. Otherwise, IsProperSubset
+	// will panic.
+	IsProperSubset(other Set) bool
+
+	// Determines if every element in the other set
+	// is in this set but the two sets are not
+	// equal.
+	//
+	// Note that the argument to IsSuperset
+	// must be of the same type as the receiver
+	// of the method. Otherwise, IsSuperset will
+	// panic.
+	IsProperSuperset(other Set) bool
+
+	// Determines if every element in this set is in
+	// the other set.
+	//
+	// Note that the argument to IsSubset
+	// must be of the same type as the receiver
+	// of the method. Otherwise, IsSubset will
+	// panic.
+	IsSubset(other Set) bool
+
+	// Determines if every element in the other set
+	// is in this set.
+	//
+	// Note that the argument to IsSuperset
+	// must be of the same type as the receiver
+	// of the method. Otherwise, IsSuperset will
+	// panic.
+	IsSuperset(other Set) bool
+
+	// Iterates over elements and executes the passed func against each element.
+	// If passed func returns true, stop iteration at the time.
+	Each(func(interface{}) bool)
+
+	// Returns a channel of elements that you can
+	// range over.
+	Iter() <-chan interface{}
+
+	// Returns an Iterator object that you can
+	// use to range over the set.
+	Iterator() *Iterator
+
+	// Remove a single element from the set.
+	Remove(i interface{})
+
+	// Provides a convenient string representation
+	// of the current state of the set.
+	String() string
+
+	// Returns a new set with all elements which are
+	// in either this set or the other set but not in both.
+	//
+	// Note that the argument to SymmetricDifference
+	// must be of the same type as the receiver
+	// of the method. Otherwise, SymmetricDifference
+	// will panic.
+	SymmetricDifference(other Set) Set
+
+	// Returns a new set with all elements in both sets.
+	//
+	// Note that the argument to Union must be of the
+
+	// same type as the receiver of the method.
+	// Otherwise, IsSuperset will panic.
+	Union(other Set) Set
+
+	// Pop removes and returns an arbitrary item from the set.
+	Pop() interface{}
+
+	// Returns all subsets of a given set (Power Set).
+	PowerSet() Set
+
+	// Returns the Cartesian Product of two sets.
+	CartesianProduct(other Set) Set
+
+	// Returns the members of the set as a slice.
+	ToSlice() []interface{}
+}
+
+// NewSet creates and returns a reference to an empty set.  Operations
+// on the resulting set are thread-safe.
+func NewSet(s ...interface{}) Set {
+	set := newThreadSafeSet()
+	for _, item := range s {
+		set.Add(item)
+	}
+	return &set
+}
+
+// NewSetWith creates and returns a new set with the given elements.
+// Operations on the resulting set are thread-safe.
+func NewSetWith(elts ...interface{}) Set {
+	return NewSetFromSlice(elts)
+}
+
+// NewSetFromSlice creates and returns a reference to a set from an
+// existing slice.  Operations on the resulting set are thread-safe.
+func NewSetFromSlice(s []interface{}) Set {
+	a := NewSet(s...)
+	return a
+}
+
+// NewThreadUnsafeSet creates and returns a reference to an empty set.
+// Operations on the resulting set are not thread-safe.
+func NewThreadUnsafeSet() Set {
+	set := newThreadUnsafeSet()
+	return &set
+}
+
+// NewThreadUnsafeSetFromSlice creates and returns a reference to a
+// set from an existing slice.  Operations on the resulting set are
+// not thread-safe.
+func NewThreadUnsafeSetFromSlice(s []interface{}) Set {
+	a := NewThreadUnsafeSet()
+	for _, item := range s {
+		a.Add(item)
+	}
+	return a
+}
diff --git a/vendor/github.com/deckarep/golang-set/threadsafe.go b/vendor/github.com/deckarep/golang-set/threadsafe.go
new file mode 100644
index 000000000..002e06af1
--- /dev/null
+++ b/vendor/github.com/deckarep/golang-set/threadsafe.go
@@ -0,0 +1,277 @@
+/*
+Open Source Initiative OSI - The MIT License (MIT):Licensing
+
+The MIT License (MIT)
+Copyright (c) 2013 Ralph Caraveo (deckarep@gmail.com)
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+*/
+
+package mapset
+
+import "sync"
+
+type threadSafeSet struct {
+	s threadUnsafeSet
+	sync.RWMutex
+}
+
+func newThreadSafeSet() threadSafeSet {
+	return threadSafeSet{s: newThreadUnsafeSet()}
+}
+
+func (set *threadSafeSet) Add(i interface{}) bool {
+	set.Lock()
+	ret := set.s.Add(i)
+	set.Unlock()
+	return ret
+}
+
+func (set *threadSafeSet) Contains(i ...interface{}) bool {
+	set.RLock()
+	ret := set.s.Contains(i...)
+	set.RUnlock()
+	return ret
+}
+
+func (set *threadSafeSet) IsSubset(other Set) bool {
+	o := other.(*threadSafeSet)
+
+	set.RLock()
+	o.RLock()
+
+	ret := set.s.IsSubset(&o.s)
+	set.RUnlock()
+	o.RUnlock()
+	return ret
+}
+
+func (set *threadSafeSet) IsProperSubset(other Set) bool {
+	o := other.(*threadSafeSet)
+
+	set.RLock()
+	defer set.RUnlock()
+	o.RLock()
+	defer o.RUnlock()
+
+	return set.s.IsProperSubset(&o.s)
+}
+
+func (set *threadSafeSet) IsSuperset(other Set) bool {
+	return other.IsSubset(set)
+}
+
+func (set *threadSafeSet) IsProperSuperset(other Set) bool {
+	return other.IsProperSubset(set)
+}
+
+func (set *threadSafeSet) Union(other Set) Set {
+	o := other.(*threadSafeSet)
+
+	set.RLock()
+	o.RLock()
+
+	unsafeUnion := set.s.Union(&o.s).(*threadUnsafeSet)
+	ret := &threadSafeSet{s: *unsafeUnion}
+	set.RUnlock()
+	o.RUnlock()
+	return ret
+}
+
+func (set *threadSafeSet) Intersect(other Set) Set {
+	o := other.(*threadSafeSet)
+
+	set.RLock()
+	o.RLock()
+
+	unsafeIntersection := set.s.Intersect(&o.s).(*threadUnsafeSet)
+	ret := &threadSafeSet{s: *unsafeIntersection}
+	set.RUnlock()
+	o.RUnlock()
+	return ret
+}
+
+func (set *threadSafeSet) Difference(other Set) Set {
+	o := other.(*threadSafeSet)
+
+	set.RLock()
+	o.RLock()
+
+	unsafeDifference := set.s.Difference(&o.s).(*threadUnsafeSet)
+	ret := &threadSafeSet{s: *unsafeDifference}
+	set.RUnlock()
+	o.RUnlock()
+	return ret
+}
+
+func (set *threadSafeSet) SymmetricDifference(other Set) Set {
+	o := other.(*threadSafeSet)
+
+	set.RLock()
+	o.RLock()
+
+	unsafeDifference := set.s.SymmetricDifference(&o.s).(*threadUnsafeSet)
+	ret := &threadSafeSet{s: *unsafeDifference}
+	set.RUnlock()
+	o.RUnlock()
+	return ret
+}
+
+func (set *threadSafeSet) Clear() {
+	set.Lock()
+	set.s = newThreadUnsafeSet()
+	set.Unlock()
+}
+
+func (set *threadSafeSet) Remove(i interface{}) {
+	set.Lock()
+	delete(set.s, i)
+	set.Unlock()
+}
+
+func (set *threadSafeSet) Cardinality() int {
+	set.RLock()
+	defer set.RUnlock()
+	return len(set.s)
+}
+
+func (set *threadSafeSet) Each(cb func(interface{}) bool) {
+	set.RLock()
+	for elem := range set.s {
+		if cb(elem) {
+			break
+		}
+	}
+	set.RUnlock()
+}
+
+func (set *threadSafeSet) Iter() <-chan interface{} {
+	ch := make(chan interface{})
+	go func() {
+		set.RLock()
+
+		for elem := range set.s {
+			ch <- elem
+		}
+		close(ch)
+		set.RUnlock()
+	}()
+
+	return ch
+}
+
+func (set *threadSafeSet) Iterator() *Iterator {
+	iterator, ch, stopCh := newIterator()
+
+	go func() {
+		set.RLock()
+	L:
+		for elem := range set.s {
+			select {
+			case <-stopCh:
+				break L
+			case ch <- elem:
+			}
+		}
+		close(ch)
+		set.RUnlock()
+	}()
+
+	return iterator
+}
+
+func (set *threadSafeSet) Equal(other Set) bool {
+	o := other.(*threadSafeSet)
+
+	set.RLock()
+	o.RLock()
+
+	ret := set.s.Equal(&o.s)
+	set.RUnlock()
+	o.RUnlock()
+	return ret
+}
+
+func (set *threadSafeSet) Clone() Set {
+	set.RLock()
+
+	unsafeClone := set.s.Clone().(*threadUnsafeSet)
+	ret := &threadSafeSet{s: *unsafeClone}
+	set.RUnlock()
+	return ret
+}
+
+func (set *threadSafeSet) String() string {
+	set.RLock()
+	ret := set.s.String()
+	set.RUnlock()
+	return ret
+}
+
+func (set *threadSafeSet) PowerSet() Set {
+	set.RLock()
+	ret := set.s.PowerSet()
+	set.RUnlock()
+	return ret
+}
+
+func (set *threadSafeSet) Pop() interface{} {
+	set.Lock()
+	defer set.Unlock()
+	return set.s.Pop()
+}
+
+func (set *threadSafeSet) CartesianProduct(other Set) Set {
+	o := other.(*threadSafeSet)
+
+	set.RLock()
+	o.RLock()
+
+	unsafeCartProduct := set.s.CartesianProduct(&o.s).(*threadUnsafeSet)
+	ret := &threadSafeSet{s: *unsafeCartProduct}
+	set.RUnlock()
+	o.RUnlock()
+	return ret
+}
+
+func (set *threadSafeSet) ToSlice() []interface{} {
+	keys := make([]interface{}, 0, set.Cardinality())
+	set.RLock()
+	for elem := range set.s {
+		keys = append(keys, elem)
+	}
+	set.RUnlock()
+	return keys
+}
+
+func (set *threadSafeSet) MarshalJSON() ([]byte, error) {
+	set.RLock()
+	b, err := set.s.MarshalJSON()
+	set.RUnlock()
+
+	return b, err
+}
+
+func (set *threadSafeSet) UnmarshalJSON(p []byte) error {
+	set.RLock()
+	err := set.s.UnmarshalJSON(p)
+	set.RUnlock()
+
+	return err
+}
diff --git a/vendor/github.com/deckarep/golang-set/threadunsafe.go b/vendor/github.com/deckarep/golang-set/threadunsafe.go
new file mode 100644
index 000000000..10bdd46f1
--- /dev/null
+++ b/vendor/github.com/deckarep/golang-set/threadunsafe.go
@@ -0,0 +1,337 @@
+/*
+Open Source Initiative OSI - The MIT License (MIT):Licensing
+
+The MIT License (MIT)
+Copyright (c) 2013 Ralph Caraveo (deckarep@gmail.com)
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+*/
+
+package mapset
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"reflect"
+	"strings"
+)
+
+type threadUnsafeSet map[interface{}]struct{}
+
+// An OrderedPair represents a 2-tuple of values.
+type OrderedPair struct {
+	First  interface{}
+	Second interface{}
+}
+
+func newThreadUnsafeSet() threadUnsafeSet {
+	return make(threadUnsafeSet)
+}
+
+// Equal says whether two 2-tuples contain the same values in the same order.
+func (pair *OrderedPair) Equal(other OrderedPair) bool {
+	if pair.First == other.First &&
+		pair.Second == other.Second {
+		return true
+	}
+
+	return false
+}
+
+func (set *threadUnsafeSet) Add(i interface{}) bool {
+	_, found := (*set)[i]
+	if found {
+		return false //False if it existed already
+	}
+
+	(*set)[i] = struct{}{}
+	return true
+}
+
+func (set *threadUnsafeSet) Contains(i ...interface{}) bool {
+	for _, val := range i {
+		if _, ok := (*set)[val]; !ok {
+			return false
+		}
+	}
+	return true
+}
+
+func (set *threadUnsafeSet) IsSubset(other Set) bool {
+	_ = other.(*threadUnsafeSet)
+	for elem := range *set {
+		if !other.Contains(elem) {
+			return false
+		}
+	}
+	return true
+}
+
+func (set *threadUnsafeSet) IsProperSubset(other Set) bool {
+	return set.IsSubset(other) && !set.Equal(other)
+}
+
+func (set *threadUnsafeSet) IsSuperset(other Set) bool {
+	return other.IsSubset(set)
+}
+
+func (set *threadUnsafeSet) IsProperSuperset(other Set) bool {
+	return set.IsSuperset(other) && !set.Equal(other)
+}
+
+func (set *threadUnsafeSet) Union(other Set) Set {
+	o := other.(*threadUnsafeSet)
+
+	unionedSet := newThreadUnsafeSet()
+
+	for elem := range *set {
+		unionedSet.Add(elem)
+	}
+	for elem := range *o {
+		unionedSet.Add(elem)
+	}
+	return &unionedSet
+}
+
+func (set *threadUnsafeSet) Intersect(other Set) Set {
+	o := other.(*threadUnsafeSet)
+
+	intersection := newThreadUnsafeSet()
+	// loop over smaller set
+	if set.Cardinality() < other.Cardinality() {
+		for elem := range *set {
+			if other.Contains(elem) {
+				intersection.Add(elem)
+			}
+		}
+	} else {
+		for elem := range *o {
+			if set.Contains(elem) {
+				intersection.Add(elem)
+			}
+		}
+	}
+	return &intersection
+}
+
+func (set *threadUnsafeSet) Difference(other Set) Set {
+	_ = other.(*threadUnsafeSet)
+
+	difference := newThreadUnsafeSet()
+	for elem := range *set {
+		if !other.Contains(elem) {
+			difference.Add(elem)
+		}
+	}
+	return &difference
+}
+
+func (set *threadUnsafeSet) SymmetricDifference(other Set) Set {
+	_ = other.(*threadUnsafeSet)
+
+	aDiff := set.Difference(other)
+	bDiff := other.Difference(set)
+	return aDiff.Union(bDiff)
+}
+
+func (set *threadUnsafeSet) Clear() {
+	*set = newThreadUnsafeSet()
+}
+
+func (set *threadUnsafeSet) Remove(i interface{}) {
+	delete(*set, i)
+}
+
+func (set *threadUnsafeSet) Cardinality() int {
+	return len(*set)
+}
+
+func (set *threadUnsafeSet) Each(cb func(interface{}) bool) {
+	for elem := range *set {
+		if cb(elem) {
+			break
+		}
+	}
+}
+
+func (set *threadUnsafeSet) Iter() <-chan interface{} {
+	ch := make(chan interface{})
+	go func() {
+		for elem := range *set {
+			ch <- elem
+		}
+		close(ch)
+	}()
+
+	return ch
+}
+
+func (set *threadUnsafeSet) Iterator() *Iterator {
+	iterator, ch, stopCh := newIterator()
+
+	go func() {
+	L:
+		for elem := range *set {
+			select {
+			case <-stopCh:
+				break L
+			case ch <- elem:
+			}
+		}
+		close(ch)
+	}()
+
+	return iterator
+}
+
+func (set *threadUnsafeSet) Equal(other Set) bool {
+	_ = other.(*threadUnsafeSet)
+
+	if set.Cardinality() != other.Cardinality() {
+		return false
+	}
+	for elem := range *set {
+		if !other.Contains(elem) {
+			return false
+		}
+	}
+	return true
+}
+
+func (set *threadUnsafeSet) Clone() Set {
+	clonedSet := newThreadUnsafeSet()
+	for elem := range *set {
+		clonedSet.Add(elem)
+	}
+	return &clonedSet
+}
+
+func (set *threadUnsafeSet) String() string {
+	items := make([]string, 0, len(*set))
+
+	for elem := range *set {
+		items = append(items, fmt.Sprintf("%v", elem))
+	}
+	return fmt.Sprintf("Set{%s}", strings.Join(items, ", "))
+}
+
+// String outputs a 2-tuple in the form "(A, B)".
+func (pair OrderedPair) String() string {
+	return fmt.Sprintf("(%v, %v)", pair.First, pair.Second)
+}
+
+func (set *threadUnsafeSet) Pop() interface{} {
+	for item := range *set {
+		delete(*set, item)
+		return item
+	}
+	return nil
+}
+
+func (set *threadUnsafeSet) PowerSet() Set {
+	powSet := NewThreadUnsafeSet()
+	nullset := newThreadUnsafeSet()
+	powSet.Add(&nullset)
+
+	for es := range *set {
+		u := newThreadUnsafeSet()
+		j := powSet.Iter()
+		for er := range j {
+			p := newThreadUnsafeSet()
+			if reflect.TypeOf(er).Name() == "" {
+				k := er.(*threadUnsafeSet)
+				for ek := range *(k) {
+					p.Add(ek)
+				}
+			} else {
+				p.Add(er)
+			}
+			p.Add(es)
+			u.Add(&p)
+		}
+
+		powSet = powSet.Union(&u)
+	}
+
+	return powSet
+}
+
+func (set *threadUnsafeSet) CartesianProduct(other Set) Set {
+	o := other.(*threadUnsafeSet)
+	cartProduct := NewThreadUnsafeSet()
+
+	for i := range *set {
+		for j := range *o {
+			elem := OrderedPair{First: i, Second: j}
+			cartProduct.Add(elem)
+		}
+	}
+
+	return cartProduct
+}
+
+func (set *threadUnsafeSet) ToSlice() []interface{} {
+	keys := make([]interface{}, 0, set.Cardinality())
+	for elem := range *set {
+		keys = append(keys, elem)
+	}
+
+	return keys
+}
+
+// MarshalJSON creates a JSON array from the set, it marshals all elements
+func (set *threadUnsafeSet) MarshalJSON() ([]byte, error) {
+	items := make([]string, 0, set.Cardinality())
+
+	for elem := range *set {
+		b, err := json.Marshal(elem)
+		if err != nil {
+			return nil, err
+		}
+
+		items = append(items, string(b))
+	}
+
+	return []byte(fmt.Sprintf("[%s]", strings.Join(items, ","))), nil
+}
+
+// UnmarshalJSON recreates a set from a JSON array, it only decodes
+// primitive types. Numbers are decoded as json.Number.
+func (set *threadUnsafeSet) UnmarshalJSON(b []byte) error {
+	var i []interface{}
+
+	d := json.NewDecoder(bytes.NewReader(b))
+	d.UseNumber()
+	err := d.Decode(&i)
+	if err != nil {
+		return err
+	}
+
+	for _, v := range i {
+		switch t := v.(type) {
+		case []interface{}, map[string]interface{}:
+			continue
+		default:
+			set.Add(t)
+		}
+	}
+
+	return nil
+}
diff --git a/vendor/gopkg.in/fatih/set.v0/README.md b/vendor/gopkg.in/fatih/set.v0/README.md
deleted file mode 100644
index 23afdd98d..000000000
--- a/vendor/gopkg.in/fatih/set.v0/README.md
+++ /dev/null
@@ -1,245 +0,0 @@
-# Set [![GoDoc](http://img.shields.io/badge/go-documentation-blue.svg?style=flat-square)](https://godoc.org/gopkg.in/fatih/set.v0) [![Build Status](http://img.shields.io/travis/fatih/set.svg?style=flat-square)](https://travis-ci.org/fatih/set)
-
-Set is a basic and simple, hash-based, **Set** data structure implementation
-in Go (Golang).
-
-Set provides both threadsafe and non-threadsafe implementations of a generic
-set data structure. The thread safety encompasses all operations on one set.
-Operations on multiple sets are consistent in that the elements of each set
-used was valid at exactly one point in time between the start and the end of
-the operation. Because it's thread safe, you can use it concurrently with your
-goroutines.
-
-For usage see examples below or click on the godoc badge.
-
-## Install and Usage
-
-Install the package with:
-
-```bash
-go get gopkg.in/fatih/set.v0
-```
-
-Import it with:
-
-```go
-import "gopkg.in/fatih/set.v0"
-```
-
-and use `set` as the package name inside the code.
-
-## Examples
-
-#### Initialization of a new Set
-
-```go
-
-// create a set with zero items
-s := set.New()
-s := set.NewNonTS() // non thread-safe version
-
-// ... or with some initial values
-s := set.New("istanbul", "frankfurt", 30.123, "san francisco", 1234)
-s := set.NewNonTS("kenya", "ethiopia", "sumatra")
-
-```
-
-#### Basic Operations
-
-```go
-// add items
-s.Add("istanbul")
-s.Add("istanbul") // nothing happens if you add duplicate item
-
-// add multiple items
-s.Add("ankara", "san francisco", 3.14)
-
-// remove item
-s.Remove("frankfurt")
-s.Remove("frankfurt") // nothing happes if you remove a nonexisting item
-
-// remove multiple items
-s.Remove("barcelona", 3.14, "ankara")
-
-// removes an arbitary item and return it
-item := s.Pop()
-
-// create a new copy
-other := s.Copy()
-
-// remove all items
-s.Clear()
-
-// number of items in the set
-len := s.Size()
-
-// return a list of items
-items := s.List()
-
-// string representation of set
-fmt.Printf("set is %s", s.String())
-
-```
-
-#### Check Operations
-
-```go
-// check for set emptiness, returns true if set is empty
-s.IsEmpty()
-
-// check for a single item exist
-s.Has("istanbul")
-
-// ... or for multiple items. This will return true if all of the items exist.
-s.Has("istanbul", "san francisco", 3.14)
-
-// create two sets for the following checks...
-s := s.New("1", "2", "3", "4", "5")
-t := s.New("1", "2", "3")
-
-
-// check if they are the same
-if !s.IsEqual(t) {
-    fmt.Println("s is not equal to t")
-}
-
-// if s contains all elements of t
-if s.IsSubset(t) {
-	fmt.Println("t is a subset of s")
-}
-
-// ... or if s is a superset of t
-if t.IsSuperset(s) {
-	fmt.Println("s is a superset of t")
-}
-
-
-```
-
-#### Set Operations
-
-
-```go
-// let us initialize two sets with some values
-a := set.New("ankara", "berlin", "san francisco")
-b := set.New("frankfurt", "berlin")
-
-// creates a new set with the items in a and b combined.
-// [frankfurt, berlin, ankara, san francisco]
-c := set.Union(a, b)
-
-// contains items which is in both a and b
-// [berlin]
-c := set.Intersection(a, b)
-
-// contains items which are in a but not in b
-// [ankara, san francisco]
-c := set.Difference(a, b)
-
-// contains items which are in one of either, but not in both.
-// [frankfurt, ankara, san francisco]
-c := set.SymmetricDifference(a, b)
-
-```
-
-```go
-// like Union but saves the result back into a.
-a.Merge(b)
-
-// removes the set items which are in b from a and saves the result back into a.
-a.Separate(b)
-
-```
-
-#### Multiple Set Operations
-
-```go
-a := set.New("1", "3", "4", "5")
-b := set.New("2", "3", "4", "5")
-c := set.New("4", "5", "6", "7")
-
-// creates a new set with items in a, b and c
-// [1 2 3 4 5 6 7]
-u := set.Union(a, b, c)
-
-// creates a new set with items in a but not in b and c
-// [1]
-u := set.Difference(a, b, c)
-
-// creates a new set with items that are common to a, b and c
-// [5]
-u := set.Intersection(a, b, c)
-```
-
-#### Helper methods
-
-The Slice functions below are a convenient way to extract or convert your Set data
-into basic data types.
-
-
-```go
-// create a set of mixed types
-s := set.New("ankara", "5", "8", "san francisco", 13, 21)
-
-
-// convert s into a slice of strings (type is []string)
-// [ankara 5 8 san francisco]
-t := set.StringSlice(s)
-
-
-// u contains a slice of ints (type is []int)
-// [13, 21]
-u := set.IntSlice(s)
-
-```
-
-#### Concurrent safe usage
-
-Below is an example of a concurrent way that uses set. We call ten functions
-concurrently and wait until they are finished. It basically creates a new
-string for each goroutine and adds it to our set.
-
-```go
-package main
-
-import (
-	"fmt"
-	"github.com/fatih/set"
-	"strconv"
-	"sync"
-)
-
-func main() {
-	var wg sync.WaitGroup // this is just for waiting until all goroutines finish
-
-	// Initialize our thread safe Set
-	s := set.New()
-
-	// Add items concurrently (item1, item2, and so on)
-	for i := 0; i < 10; i++ {
-		wg.Add(1)
-		go func(i int) {
-			item := "item" + strconv.Itoa(i)
-			fmt.Println("adding", item)
-			s.Add(item)
-			wg.Done()
-		}(i)
-	}
-
-	// Wait until all concurrent calls finished and print our set
-	wg.Wait()
-	fmt.Println(s)
-}
-```
-
-## Credits
-
- * [Fatih Arslan](https://github.com/fatih)
- * [Arne Hormann](https://github.com/arnehormann)
- * [Sam Boyer](https://github.com/sdboyer)
- * [Ralph Loizzo](https://github.com/friartech)
-
-## License
-
-The MIT License (MIT) - see LICENSE.md for more details
-
diff --git a/vendor/gopkg.in/fatih/set.v0/set.go b/vendor/gopkg.in/fatih/set.v0/set.go
deleted file mode 100644
index ac0240ce7..000000000
--- a/vendor/gopkg.in/fatih/set.v0/set.go
+++ /dev/null
@@ -1,121 +0,0 @@
-// Package set provides both threadsafe and non-threadsafe implementations of
-// a generic set data structure. In the threadsafe set, safety encompasses all
-// operations on one set. Operations on multiple sets are consistent in that
-// the elements of each set used was valid at exactly one point in time
-// between the start and the end of the operation.
-package set
-
-// Interface is describing a Set. Sets are an unordered, unique list of values.
-type Interface interface {
-	New(items ...interface{}) Interface
-	Add(items ...interface{})
-	Remove(items ...interface{})
-	Pop() interface{}
-	Has(items ...interface{}) bool
-	Size() int
-	Clear()
-	IsEmpty() bool
-	IsEqual(s Interface) bool
-	IsSubset(s Interface) bool
-	IsSuperset(s Interface) bool
-	Each(func(interface{}) bool)
-	String() string
-	List() []interface{}
-	Copy() Interface
-	Merge(s Interface)
-	Separate(s Interface)
-}
-
-// helpful to not write everywhere struct{}{}
-var keyExists = struct{}{}
-
-// Union is the merger of multiple sets. It returns a new set with all the
-// elements present in all the sets that are passed.
-//
-// The dynamic type of the returned set is determined by the first passed set's
-// implementation of the New() method.
-func Union(set1, set2 Interface, sets ...Interface) Interface {
-	u := set1.Copy()
-	set2.Each(func(item interface{}) bool {
-		u.Add(item)
-		return true
-	})
-	for _, set := range sets {
-		set.Each(func(item interface{}) bool {
-			u.Add(item)
-			return true
-		})
-	}
-
-	return u
-}
-
-// Difference returns a new set which contains items which are in in the first
-// set but not in the others. Unlike the Difference() method you can use this
-// function separately with multiple sets.
-func Difference(set1, set2 Interface, sets ...Interface) Interface {
-	s := set1.Copy()
-	s.Separate(set2)
-	for _, set := range sets {
-		s.Separate(set) // seperate is thread safe
-	}
-	return s
-}
-
-// Intersection returns a new set which contains items that only exist in all given sets.
-func Intersection(set1, set2 Interface, sets ...Interface) Interface {
-	all := Union(set1, set2, sets...)
-	result := Union(set1, set2, sets...)
-
-	all.Each(func(item interface{}) bool {
-		if !set1.Has(item) || !set2.Has(item) {
-			result.Remove(item)
-		}
-
-		for _, set := range sets {
-			if !set.Has(item) {
-				result.Remove(item)
-			}
-		}
-		return true
-	})
-	return result
-}
-
-// SymmetricDifference returns a new set which s is the difference of items which are in
-// one of either, but not in both.
-func SymmetricDifference(s Interface, t Interface) Interface {
-	u := Difference(s, t)
-	v := Difference(t, s)
-	return Union(u, v)
-}
-
-// StringSlice is a helper function that returns a slice of strings of s. If
-// the set contains mixed types of items only items of type string are returned.
-func StringSlice(s Interface) []string {
-	slice := make([]string, 0)
-	for _, item := range s.List() {
-		v, ok := item.(string)
-		if !ok {
-			continue
-		}
-
-		slice = append(slice, v)
-	}
-	return slice
-}
-
-// IntSlice is a helper function that returns a slice of ints of s. If
-// the set contains mixed types of items only items of type int are returned.
-func IntSlice(s Interface) []int {
-	slice := make([]int, 0)
-	for _, item := range s.List() {
-		v, ok := item.(int)
-		if !ok {
-			continue
-		}
-
-		slice = append(slice, v)
-	}
-	return slice
-}
diff --git a/vendor/gopkg.in/fatih/set.v0/set_nots.go b/vendor/gopkg.in/fatih/set.v0/set_nots.go
deleted file mode 100644
index ec1ab2285..000000000
--- a/vendor/gopkg.in/fatih/set.v0/set_nots.go
+++ /dev/null
@@ -1,195 +0,0 @@
-package set
-
-import (
-	"fmt"
-	"strings"
-)
-
-// Provides a common set baseline for both threadsafe and non-ts Sets.
-type set struct {
-	m map[interface{}]struct{} // struct{} doesn't take up space
-}
-
-// SetNonTS defines a non-thread safe set data structure.
-type SetNonTS struct {
-	set
-}
-
-// NewNonTS creates and initialize a new non-threadsafe Set.
-// It accepts a variable number of arguments to populate the initial set.
-// If nothing is passed a SetNonTS with zero size is created.
-func NewNonTS(items ...interface{}) *SetNonTS {
-	s := &SetNonTS{}
-	s.m = make(map[interface{}]struct{})
-
-	// Ensure interface compliance
-	var _ Interface = s
-
-	s.Add(items...)
-	return s
-}
-
-// New creates and initalizes a new Set interface. It accepts a variable
-// number of arguments to populate the initial set. If nothing is passed a
-// zero size Set based on the struct is created.
-func (s *set) New(items ...interface{}) Interface {
-	return NewNonTS(items...)
-}
-
-// Add includes the specified items (one or more) to the set. The underlying
-// Set s is modified. If passed nothing it silently returns.
-func (s *set) Add(items ...interface{}) {
-	if len(items) == 0 {
-		return
-	}
-
-	for _, item := range items {
-		s.m[item] = keyExists
-	}
-}
-
-// Remove deletes the specified items from the set.  The underlying Set s is
-// modified. If passed nothing it silently returns.
-func (s *set) Remove(items ...interface{}) {
-	if len(items) == 0 {
-		return
-	}
-
-	for _, item := range items {
-		delete(s.m, item)
-	}
-}
-
-// Pop  deletes and return an item from the set. The underlying Set s is
-// modified. If set is empty, nil is returned.
-func (s *set) Pop() interface{} {
-	for item := range s.m {
-		delete(s.m, item)
-		return item
-	}
-	return nil
-}
-
-// Has looks for the existence of items passed. It returns false if nothing is
-// passed. For multiple items it returns true only if all of  the items exist.
-func (s *set) Has(items ...interface{}) bool {
-	// assume checked for empty item, which not exist
-	if len(items) == 0 {
-		return false
-	}
-
-	has := true
-	for _, item := range items {
-		if _, has = s.m[item]; !has {
-			break
-		}
-	}
-	return has
-}
-
-// Size returns the number of items in a set.
-func (s *set) Size() int {
-	return len(s.m)
-}
-
-// Clear removes all items from the set.
-func (s *set) Clear() {
-	s.m = make(map[interface{}]struct{})
-}
-
-// IsEmpty reports whether the Set is empty.
-func (s *set) IsEmpty() bool {
-	return s.Size() == 0
-}
-
-// IsEqual test whether s and t are the same in size and have the same items.
-func (s *set) IsEqual(t Interface) bool {
-	// Force locking only if given set is threadsafe.
-	if conv, ok := t.(*Set); ok {
-		conv.l.RLock()
-		defer conv.l.RUnlock()
-	}
-
-	// return false if they are no the same size
-	if sameSize := len(s.m) == t.Size(); !sameSize {
-		return false
-	}
-
-	equal := true
-	t.Each(func(item interface{}) bool {
-		_, equal = s.m[item]
-		return equal // if false, Each() will end
-	})
-
-	return equal
-}
-
-// IsSubset tests whether t is a subset of s.
-func (s *set) IsSubset(t Interface) (subset bool) {
-	subset = true
-
-	t.Each(func(item interface{}) bool {
-		_, subset = s.m[item]
-		return subset
-	})
-
-	return
-}
-
-// IsSuperset tests whether t is a superset of s.
-func (s *set) IsSuperset(t Interface) bool {
-	return t.IsSubset(s)
-}
-
-// Each traverses the items in the Set, calling the provided function for each
-// set member. Traversal will continue until all items in the Set have been
-// visited, or if the closure returns false.
-func (s *set) Each(f func(item interface{}) bool) {
-	for item := range s.m {
-		if !f(item) {
-			break
-		}
-	}
-}
-
-// String returns a string representation of s
-func (s *set) String() string {
-	t := make([]string, 0, len(s.List()))
-	for _, item := range s.List() {
-		t = append(t, fmt.Sprintf("%v", item))
-	}
-
-	return fmt.Sprintf("[%s]", strings.Join(t, ", "))
-}
-
-// List returns a slice of all items. There is also StringSlice() and
-// IntSlice() methods for returning slices of type string or int.
-func (s *set) List() []interface{} {
-	list := make([]interface{}, 0, len(s.m))
-
-	for item := range s.m {
-		list = append(list, item)
-	}
-
-	return list
-}
-
-// Copy returns a new Set with a copy of s.
-func (s *set) Copy() Interface {
-	return NewNonTS(s.List()...)
-}
-
-// Merge is like Union, however it modifies the current set it's applied on
-// with the given t set.
-func (s *set) Merge(t Interface) {
-	t.Each(func(item interface{}) bool {
-		s.m[item] = keyExists
-		return true
-	})
-}
-
-// it's not the opposite of Merge.
-// Separate removes the set items containing in t from set s. Please aware that
-func (s *set) Separate(t Interface) {
-	s.Remove(t.List()...)
-}
diff --git a/vendor/gopkg.in/fatih/set.v0/set_ts.go b/vendor/gopkg.in/fatih/set.v0/set_ts.go
deleted file mode 100644
index 50f532565..000000000
--- a/vendor/gopkg.in/fatih/set.v0/set_ts.go
+++ /dev/null
@@ -1,200 +0,0 @@
-package set
-
-import (
-	"sync"
-)
-
-// Set defines a thread safe set data structure.
-type Set struct {
-	set
-	l sync.RWMutex // we name it because we don't want to expose it
-}
-
-// New creates and initialize a new Set. It's accept a variable number of
-// arguments to populate the initial set. If nothing passed a Set with zero
-// size is created.
-func New(items ...interface{}) *Set {
-	s := &Set{}
-	s.m = make(map[interface{}]struct{})
-
-	// Ensure interface compliance
-	var _ Interface = s
-
-	s.Add(items...)
-	return s
-}
-
-// New creates and initalizes a new Set interface. It accepts a variable
-// number of arguments to populate the initial set. If nothing is passed a
-// zero size Set based on the struct is created.
-func (s *Set) New(items ...interface{}) Interface {
-	return New(items...)
-}
-
-// Add includes the specified items (one or more) to the set. The underlying
-// Set s is modified. If passed nothing it silently returns.
-func (s *Set) Add(items ...interface{}) {
-	if len(items) == 0 {
-		return
-	}
-
-	s.l.Lock()
-	defer s.l.Unlock()
-
-	for _, item := range items {
-		s.m[item] = keyExists
-	}
-}
-
-// Remove deletes the specified items from the set.  The underlying Set s is
-// modified. If passed nothing it silently returns.
-func (s *Set) Remove(items ...interface{}) {
-	if len(items) == 0 {
-		return
-	}
-
-	s.l.Lock()
-	defer s.l.Unlock()
-
-	for _, item := range items {
-		delete(s.m, item)
-	}
-}
-
-// Pop  deletes and return an item from the set. The underlying Set s is
-// modified. If set is empty, nil is returned.
-func (s *Set) Pop() interface{} {
-	s.l.RLock()
-	for item := range s.m {
-		s.l.RUnlock()
-		s.l.Lock()
-		delete(s.m, item)
-		s.l.Unlock()
-		return item
-	}
-	s.l.RUnlock()
-	return nil
-}
-
-// Has looks for the existence of items passed. It returns false if nothing is
-// passed. For multiple items it returns true only if all of  the items exist.
-func (s *Set) Has(items ...interface{}) bool {
-	// assume checked for empty item, which not exist
-	if len(items) == 0 {
-		return false
-	}
-
-	s.l.RLock()
-	defer s.l.RUnlock()
-
-	has := true
-	for _, item := range items {
-		if _, has = s.m[item]; !has {
-			break
-		}
-	}
-	return has
-}
-
-// Size returns the number of items in a set.
-func (s *Set) Size() int {
-	s.l.RLock()
-	defer s.l.RUnlock()
-
-	l := len(s.m)
-	return l
-}
-
-// Clear removes all items from the set.
-func (s *Set) Clear() {
-	s.l.Lock()
-	defer s.l.Unlock()
-
-	s.m = make(map[interface{}]struct{})
-}
-
-// IsEqual test whether s and t are the same in size and have the same items.
-func (s *Set) IsEqual(t Interface) bool {
-	s.l.RLock()
-	defer s.l.RUnlock()
-
-	// Force locking only if given set is threadsafe.
-	if conv, ok := t.(*Set); ok {
-		conv.l.RLock()
-		defer conv.l.RUnlock()
-	}
-
-	// return false if they are no the same size
-	if sameSize := len(s.m) == t.Size(); !sameSize {
-		return false
-	}
-
-	equal := true
-	t.Each(func(item interface{}) bool {
-		_, equal = s.m[item]
-		return equal // if false, Each() will end
-	})
-
-	return equal
-}
-
-// IsSubset tests whether t is a subset of s.
-func (s *Set) IsSubset(t Interface) (subset bool) {
-	s.l.RLock()
-	defer s.l.RUnlock()
-
-	subset = true
-
-	t.Each(func(item interface{}) bool {
-		_, subset = s.m[item]
-		return subset
-	})
-
-	return
-}
-
-// Each traverses the items in the Set, calling the provided function for each
-// set member. Traversal will continue until all items in the Set have been
-// visited, or if the closure returns false.
-func (s *Set) Each(f func(item interface{}) bool) {
-	s.l.RLock()
-	defer s.l.RUnlock()
-
-	for item := range s.m {
-		if !f(item) {
-			break
-		}
-	}
-}
-
-// List returns a slice of all items. There is also StringSlice() and
-// IntSlice() methods for returning slices of type string or int.
-func (s *Set) List() []interface{} {
-	s.l.RLock()
-	defer s.l.RUnlock()
-
-	list := make([]interface{}, 0, len(s.m))
-
-	for item := range s.m {
-		list = append(list, item)
-	}
-
-	return list
-}
-
-// Copy returns a new Set with a copy of s.
-func (s *Set) Copy() Interface {
-	return New(s.List()...)
-}
-
-// Merge is like Union, however it modifies the current set it's applied on
-// with the given t set.
-func (s *Set) Merge(t Interface) {
-	s.l.Lock()
-	defer s.l.Unlock()
-
-	t.Each(func(item interface{}) bool {
-		s.m[item] = keyExists
-		return true
-	})
-}
diff --git a/vendor/vendor.json b/vendor/vendor.json
index 66a61dcec..00729ca47 100644
--- a/vendor/vendor.json
+++ b/vendor/vendor.json
@@ -81,6 +81,12 @@
 			"revisionTime": "2016-10-29T20:57:26Z"
 		},
 		{
+			"checksumSHA1": "1xK7ycc1ICRInk/S9iiyB9Rpv50=",
+			"path": "github.com/deckarep/golang-set",
+			"revision": "504e848d77ea4752b3057b8fb46da0e7f746ccf3",
+			"revisionTime": "2018-06-03T19:32:48Z"
+		},
+		{
 			"checksumSHA1": "2Fy1Y6Z3lRRX1891WF/+HT4XS2I=",
 			"path": "github.com/dgrijalva/jwt-go",
 			"revision": "2268707a8f0843315e2004ee4f1d021dc08baedf",
@@ -892,12 +898,6 @@
 			"revisionTime": "2016-12-08T18:13:25Z"
 		},
 		{
-			"checksumSHA1": "NGg7/qIJVUfXi7xnEyyDLocdi6Y=",
-			"path": "gopkg.in/fatih/set.v0",
-			"revision": "27c40922c40b43fe04554d8223a402af3ea333f3",
-			"revisionTime": "2014-12-10T08:48:24Z"
-		},
-		{
 			"checksumSHA1": "DQXNV0EivoHm4q+bkdahYXrjjfE=",
 			"path": "gopkg.in/karalabe/cookiejar.v2/collections/prque",
 			"revision": "8dcd6a7f4951f6ff3ee9cbb919a06d8925822e57",
diff --git a/whisper/whisperv5/peer.go b/whisper/whisperv5/peer.go
index da0763199..2bb5677c7 100644
--- a/whisper/whisperv5/peer.go
+++ b/whisper/whisperv5/peer.go
@@ -20,11 +20,11 @@ import (
 	"fmt"
 	"time"
 
+	mapset "github.com/deckarep/golang-set"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/p2p"
 	"github.com/ethereum/go-ethereum/rlp"
-	set "gopkg.in/fatih/set.v0"
 )
 
 // Peer represents a whisper protocol peer connection.
@@ -34,7 +34,7 @@ type Peer struct {
 	ws      p2p.MsgReadWriter
 	trusted bool
 
-	known *set.Set // Messages already known by the peer to avoid wasting bandwidth
+	known mapset.Set // Messages already known by the peer to avoid wasting bandwidth
 
 	quit chan struct{}
 }
@@ -46,7 +46,7 @@ func newPeer(host *Whisper, remote *p2p.Peer, rw p2p.MsgReadWriter) *Peer {
 		peer:    remote,
 		ws:      rw,
 		trusted: false,
-		known:   set.New(),
+		known:   mapset.NewSet(),
 		quit:    make(chan struct{}),
 	}
 }
@@ -127,7 +127,7 @@ func (peer *Peer) mark(envelope *Envelope) {
 
 // marked checks if an envelope is already known to the remote peer.
 func (peer *Peer) marked(envelope *Envelope) bool {
-	return peer.known.Has(envelope.Hash())
+	return peer.known.Contains(envelope.Hash())
 }
 
 // expire iterates over all the known envelopes in the host and removes all
diff --git a/whisper/whisperv5/whisper.go b/whisper/whisperv5/whisper.go
index cec233cb0..5a2b25c9e 100644
--- a/whisper/whisperv5/whisper.go
+++ b/whisper/whisperv5/whisper.go
@@ -26,6 +26,7 @@ import (
 	"sync"
 	"time"
 
+	mapset "github.com/deckarep/golang-set"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/log"
@@ -34,7 +35,6 @@ import (
 	"github.com/syndtr/goleveldb/leveldb/errors"
 	"golang.org/x/crypto/pbkdf2"
 	"golang.org/x/sync/syncmap"
-	set "gopkg.in/fatih/set.v0"
 )
 
 type Statistics struct {
@@ -63,7 +63,7 @@ type Whisper struct {
 
 	poolMu      sync.RWMutex              // Mutex to sync the message and expiration pools
 	envelopes   map[common.Hash]*Envelope // Pool of envelopes currently tracked by this node
-	expirations map[uint32]*set.SetNonTS  // Message expiration pool
+	expirations map[uint32]mapset.Set     // Message expiration pool
 
 	peerMu sync.RWMutex       // Mutex to sync the active peer set
 	peers  map[*Peer]struct{} // Set of currently active peers
@@ -90,7 +90,7 @@ func New(cfg *Config) *Whisper {
 		privateKeys:  make(map[string]*ecdsa.PrivateKey),
 		symKeys:      make(map[string][]byte),
 		envelopes:    make(map[common.Hash]*Envelope),
-		expirations:  make(map[uint32]*set.SetNonTS),
+		expirations:  make(map[uint32]mapset.Set),
 		peers:        make(map[*Peer]struct{}),
 		messageQueue: make(chan *Envelope, messageQueueLimit),
 		p2pMsgQueue:  make(chan *Envelope, messageQueueLimit),
@@ -608,9 +608,9 @@ func (w *Whisper) add(envelope *Envelope) (bool, error) {
 	if !alreadyCached {
 		w.envelopes[hash] = envelope
 		if w.expirations[envelope.Expiry] == nil {
-			w.expirations[envelope.Expiry] = set.NewNonTS()
+			w.expirations[envelope.Expiry] = mapset.NewThreadUnsafeSet()
 		}
-		if !w.expirations[envelope.Expiry].Has(hash) {
+		if !w.expirations[envelope.Expiry].Contains(hash) {
 			w.expirations[envelope.Expiry].Add(hash)
 		}
 	}
diff --git a/whisper/whisperv6/api_test.go b/whisper/whisperv6/api_test.go
index 004a41c94..cdbc7fab5 100644
--- a/whisper/whisperv6/api_test.go
+++ b/whisper/whisperv6/api_test.go
@@ -22,8 +22,8 @@ import (
 	"testing"
 	"time"
 
+	mapset "github.com/deckarep/golang-set"
 	"github.com/ethereum/go-ethereum/common"
-	set "gopkg.in/fatih/set.v0"
 )
 
 func TestMultipleTopicCopyInNewMessageFilter(t *testing.T) {
@@ -31,7 +31,7 @@ func TestMultipleTopicCopyInNewMessageFilter(t *testing.T) {
 		privateKeys:   make(map[string]*ecdsa.PrivateKey),
 		symKeys:       make(map[string][]byte),
 		envelopes:     make(map[common.Hash]*Envelope),
-		expirations:   make(map[uint32]*set.SetNonTS),
+		expirations:   make(map[uint32]mapset.Set),
 		peers:         make(map[*Peer]struct{}),
 		messageQueue:  make(chan *Envelope, messageQueueLimit),
 		p2pMsgQueue:   make(chan *Envelope, messageQueueLimit),
diff --git a/whisper/whisperv6/peer.go b/whisper/whisperv6/peer.go
index 2bf1c905b..79cc21270 100644
--- a/whisper/whisperv6/peer.go
+++ b/whisper/whisperv6/peer.go
@@ -22,11 +22,11 @@ import (
 	"sync"
 	"time"
 
+	mapset "github.com/deckarep/golang-set"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/p2p"
 	"github.com/ethereum/go-ethereum/rlp"
-	set "gopkg.in/fatih/set.v0"
 )
 
 // Peer represents a whisper protocol peer connection.
@@ -41,7 +41,7 @@ type Peer struct {
 	bloomFilter    []byte
 	fullNode       bool
 
-	known *set.Set // Messages already known by the peer to avoid wasting bandwidth
+	known mapset.Set // Messages already known by the peer to avoid wasting bandwidth
 
 	quit chan struct{}
 }
@@ -54,7 +54,7 @@ func newPeer(host *Whisper, remote *p2p.Peer, rw p2p.MsgReadWriter) *Peer {
 		ws:             rw,
 		trusted:        false,
 		powRequirement: 0.0,
-		known:          set.New(),
+		known:          mapset.NewSet(),
 		quit:           make(chan struct{}),
 		bloomFilter:    MakeFullNodeBloom(),
 		fullNode:       true,
@@ -165,7 +165,7 @@ func (peer *Peer) mark(envelope *Envelope) {
 
 // marked checks if an envelope is already known to the remote peer.
 func (peer *Peer) marked(envelope *Envelope) bool {
-	return peer.known.Has(envelope.Hash())
+	return peer.known.Contains(envelope.Hash())
 }
 
 // expire iterates over all the known envelopes in the host and removes all
diff --git a/whisper/whisperv6/whisper.go b/whisper/whisperv6/whisper.go
index 3418c7bf7..76d485808 100644
--- a/whisper/whisperv6/whisper.go
+++ b/whisper/whisperv6/whisper.go
@@ -26,6 +26,7 @@ import (
 	"sync"
 	"time"
 
+	mapset "github.com/deckarep/golang-set"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/log"
@@ -35,7 +36,6 @@ import (
 	"github.com/syndtr/goleveldb/leveldb/errors"
 	"golang.org/x/crypto/pbkdf2"
 	"golang.org/x/sync/syncmap"
-	set "gopkg.in/fatih/set.v0"
 )
 
 // Statistics holds several message-related counter for analytics
@@ -69,7 +69,7 @@ type Whisper struct {
 
 	poolMu      sync.RWMutex              // Mutex to sync the message and expiration pools
 	envelopes   map[common.Hash]*Envelope // Pool of envelopes currently tracked by this node
-	expirations map[uint32]*set.SetNonTS  // Message expiration pool
+	expirations map[uint32]mapset.Set     // Message expiration pool
 
 	peerMu sync.RWMutex       // Mutex to sync the active peer set
 	peers  map[*Peer]struct{} // Set of currently active peers
@@ -100,7 +100,7 @@ func New(cfg *Config) *Whisper {
 		privateKeys:   make(map[string]*ecdsa.PrivateKey),
 		symKeys:       make(map[string][]byte),
 		envelopes:     make(map[common.Hash]*Envelope),
-		expirations:   make(map[uint32]*set.SetNonTS),
+		expirations:   make(map[uint32]mapset.Set),
 		peers:         make(map[*Peer]struct{}),
 		messageQueue:  make(chan *Envelope, messageQueueLimit),
 		p2pMsgQueue:   make(chan *Envelope, messageQueueLimit),
@@ -796,9 +796,9 @@ func (whisper *Whisper) add(envelope *Envelope, isP2P bool) (bool, error) {
 	if !alreadyCached {
 		whisper.envelopes[hash] = envelope
 		if whisper.expirations[envelope.Expiry] == nil {
-			whisper.expirations[envelope.Expiry] = set.NewNonTS()
+			whisper.expirations[envelope.Expiry] = mapset.NewThreadUnsafeSet()
 		}
-		if !whisper.expirations[envelope.Expiry].Has(hash) {
+		if !whisper.expirations[envelope.Expiry].Contains(hash) {
 			whisper.expirations[envelope.Expiry].Add(hash)
 		}
 	}