drop transactions who's nonce is lower then the known network nonce but were not included in a block (#6388)

* transactions/pending - check nonce against the network and mark as dropped if not included in a block

* transactions/pending - unifiy "dropped" txs

* transactions/pending - test - fix for new expected behavior

* fix comment

* transactions/pending - clean up dropped event

* fix spelling

Co-Authored-By: frankiebee <frankie.diamond@gmail.com>

* nit fix

* test/tx-pending - clarify test description

2 files changed, 46 insertions, 8 deletions

diff --git a/app/scripts/controllers/transactions/index.js b/app/scripts/controllers/transactions/index.js
index 79dba7833..dd497a11e 100644
--- a/app/scripts/controllers/transactions/index.js
+++ b/app/scripts/controllers/transactions/index.js
@@ -555,6 +555,7 @@ class TransactionController extends EventEmitter {
     })
     this.pendingTxTracker.on('tx:failed', this.txStateManager.setTxStatusFailed.bind(this.txStateManager))
     this.pendingTxTracker.on('tx:confirmed', (txId) => this.confirmTransaction(txId))
+    this.pendingTxTracker.on('tx:dropped', this.txStateManager.setTxStatusDropped.bind(this.txStateManager))
     this.pendingTxTracker.on('tx:block-update', (txMeta, latestBlockNumber) => {
       if (!txMeta.firstRetryBlockNumber) {
         txMeta.firstRetryBlockNumber = latestBlockNumber
diff --git a/app/scripts/controllers/transactions/pending-tx-tracker.js b/app/scripts/controllers/transactions/pending-tx-tracker.js
index 4bf40b1db..bc11f6633 100644
--- a/app/scripts/controllers/transactions/pending-tx-tracker.js
+++ b/app/scripts/controllers/transactions/pending-tx-tracker.js
@@ -22,6 +22,7 @@ const EthQuery = require('ethjs-query')
 class PendingTransactionTracker extends EventEmitter {
   constructor (config) {
     super()
+    this.droppedBuffer = {}
     this.query = new EthQuery(config.provider)
     this.nonceTracker = config.nonceTracker
     this.getPendingTransactions = config.getPendingTransactions
@@ -139,22 +140,42 @@ class PendingTransactionTracker extends EventEmitter {
       const noTxHashErr = new Error('We had an error while submitting this transaction, please try again.')
       noTxHashErr.name = 'NoTxHashError'
       this.emit('tx:failed', txId, noTxHashErr)
+
       return
     }
 
-    // If another tx with the same nonce is mined, set as failed.
+    // If another tx with the same nonce is mined, set as dropped.
     const taken = await this._checkIfNonceIsTaken(txMeta)
-    if (taken) {
-      const nonceTakenErr = new Error('Another transaction with this nonce has been mined.')
-      nonceTakenErr.name = 'NonceTakenErr'
-      return this.emit('tx:failed', txId, nonceTakenErr)
+    let dropped
+    try {
+      // check the network if the nonce is ahead the tx
+      // and the tx has not been mined into a block
+
+      dropped = await this._checkIftxWasDropped(txMeta)
+      // the dropped buffer is in case we ask a node for the tx
+      // that is behind the node we asked for tx count
+      // IS A SECURITY FOR HITTING NODES IN INFURA THAT COULD GO OUT
+      // OF SYNC.
+      // on the next block event it will return fire as dropped
+      if (dropped && !this.droppedBuffer[txHash]) {
+        this.droppedBuffer[txHash] = true
+        dropped = false
+      } else if (dropped && this.droppedBuffer[txHash]) {
+        // clean up
+        delete this.droppedBuffer[txHash]
+      }
+
+    } catch (e) {
+      log.error(e)
+    }
+    if (taken || dropped) {
+      return this.emit('tx:dropped', txId)
     }
 
     // get latest transaction status
     try {
-      const txParams = await this.query.getTransactionByHash(txHash)
-      if (!txParams) return
-      if (txParams.blockNumber) {
+      const { blockNumber } = await this.query.getTransactionByHash(txHash) || {}
+      if (blockNumber) {
         this.emit('tx:confirmed', txId)
       }
     } catch (err) {
@@ -165,6 +186,22 @@ class PendingTransactionTracker extends EventEmitter {
       this.emit('tx:warning', txMeta, err)
     }
   }
+    /**
+    checks to see if if the tx's nonce has been used by another transaction
+    @param txMeta {Object} - txMeta object
+    @emits tx:dropped
+    @returns {boolean}
+  */
+
+  async _checkIftxWasDropped (txMeta) {
+    const { txParams: { nonce, from }, hash } = txMeta
+    const nextNonce = await this.query.getTransactionCount(from)
+    const { blockNumber } = await this.query.getTransactionByHash(hash) || {}
+    if (!blockNumber && parseInt(nextNonce) > parseInt(nonce)) {
+        return true
+    }
+    return false
+  }
 
   /**
     checks to see if a confirmed txMeta has the same nonce