libs/common: remove heap.go (#3780)

* Remove file heap.go

- cmn.Heap is not being used in cosmos-sdk, iavl nor tendermint repo.

Signed-off-by: Marko Baricevic <marbar3778@yahoo.com>

* changelog entry

* Update CHANGELOG_PENDING.md

closes #2432

CHANGELOG_PENDING.md

@@ -1,6 +1,6 @@
 ## v0.32.1
 
-**
+\*\*
 
 Special thanks to external contributors on this release:
 
@@ -9,33 +9,37 @@ program](https://hackerone.com/tendermint).
 
 ### BREAKING CHANGES:
 
-* CLI/RPC/Config
+- CLI/RPC/Config
 
-* Apps
+- Apps
+
+- Go API
 
-* Go API
   - [abci] \#2127 ABCI / mempool: Add a "Recheck Tx" indicator. Breaks the ABCI
     client interface (`abcicli.Client`) to allow for supplying the ABCI
     `types.RequestCheckTx` and `types.RequestDeliverTx` structs, and lets the
     mempool indicate to the ABCI app whether a CheckTx request is a recheck or
     not.
   - [libs] Remove unused `db/debugDB` and `common/colors.go` & `errors/errors.go` files (@marbar3778)
+  - [libs] \#2432 Remove unused `common/heap.go` file (@marbar3778)
 
-* Blockchain Protocol
+- Blockchain Protocol
 
-* P2P Protocol
+- P2P Protocol
 
 ### FEATURES:
+
 - [node] Refactor `NewNode` to use functional options to make it more flexible
   and extensible in the future.
-- [node] [\#3730](https://github.com/tendermint/tendermint/pull/3730) Add `CustomReactors` option to `NewNode` allowing caller to pass
+- [node][\#3730](https://github.com/tendermint/tendermint/pull/3730) Add `CustomReactors` option to `NewNode` allowing caller to pass
   custom reactors to run inside Tendermint node (@ParthDesai)
 
 ### IMPROVEMENTS:
-  - [rpc] \#3700 Make possible to set absolute paths for TLS cert and key (@climber73)
+
+- [rpc] \#3700 Make possible to set absolute paths for TLS cert and key (@climber73)
 
 ### BUG FIXES:
+
 - [p2p] \#3338 Prevent "sent next PEX request too soon" errors by not calling
   ensurePeers outside of ensurePeersRoutine
 - [behaviour] Return correct reason in MessageOutOfOrder (@jim380)
-  

libs/common/heap.go

@@ -1,125 +0,0 @@
-package common
-
-import (
-	"bytes"
-	"container/heap"
-)
-
-/*
-	Example usage:
-
-	```
-	h := NewHeap()
-
-	h.Push("msg1", 1)
-	h.Push("msg3", 3)
-	h.Push("msg2", 2)
-
-	fmt.Println(h.Pop()) // msg1
-	fmt.Println(h.Pop()) // msg2
-	fmt.Println(h.Pop()) // msg3
-	```
-*/
-type Heap struct {
-	pq priorityQueue
-}
-
-func NewHeap() *Heap {
-	return &Heap{pq: make([]*pqItem, 0)}
-}
-
-func (h *Heap) Len() int64 {
-	return int64(len(h.pq))
-}
-
-func (h *Heap) Push(value interface{}, priority int) {
-	heap.Push(&h.pq, &pqItem{value: value, priority: cmpInt(priority)})
-}
-
-func (h *Heap) PushBytes(value interface{}, priority []byte) {
-	heap.Push(&h.pq, &pqItem{value: value, priority: cmpBytes(priority)})
-}
-
-func (h *Heap) PushComparable(value interface{}, priority Comparable) {
-	heap.Push(&h.pq, &pqItem{value: value, priority: priority})
-}
-
-func (h *Heap) Peek() interface{} {
-	if len(h.pq) == 0 {
-		return nil
-	}
-	return h.pq[0].value
-}
-
-func (h *Heap) Update(value interface{}, priority Comparable) {
-	h.pq.Update(h.pq[0], value, priority)
-}
-
-func (h *Heap) Pop() interface{} {
-	item := heap.Pop(&h.pq).(*pqItem)
-	return item.value
-}
-
-//-----------------------------------------------------------------------------
-// From: http://golang.org/pkg/container/heap/#example__priorityQueue
-
-type pqItem struct {
-	value    interface{}
-	priority Comparable
-	index    int
-}
-
-type priorityQueue []*pqItem
-
-func (pq priorityQueue) Len() int { return len(pq) }
-
-func (pq priorityQueue) Less(i, j int) bool {
-	return pq[i].priority.Less(pq[j].priority)
-}
-
-func (pq priorityQueue) Swap(i, j int) {
-	pq[i], pq[j] = pq[j], pq[i]
-	pq[i].index = i
-	pq[j].index = j
-}
-
-func (pq *priorityQueue) Push(x interface{}) {
-	n := len(*pq)
-	item := x.(*pqItem)
-	item.index = n
-	*pq = append(*pq, item)
-}
-
-func (pq *priorityQueue) Pop() interface{} {
-	old := *pq
-	n := len(old)
-	item := old[n-1]
-	item.index = -1 // for safety
-	*pq = old[0 : n-1]
-	return item
-}
-
-func (pq *priorityQueue) Update(item *pqItem, value interface{}, priority Comparable) {
-	item.value = value
-	item.priority = priority
-	heap.Fix(pq, item.index)
-}
-
-//--------------------------------------------------------------------------------
-// Comparable
-
-type Comparable interface {
-	Less(o interface{}) bool
-}
-
-type cmpInt int
-
-func (i cmpInt) Less(o interface{}) bool {
-	return int(i) < int(o.(cmpInt))
-}
-
-type cmpBytes []byte
-
-func (bz cmpBytes) Less(o interface{}) bool {
-	return bytes.Compare([]byte(bz), []byte(o.(cmpBytes))) < 0
-}