fix: avoid sync callbacks in async code

src/decision-engine/index.js

@@ -71,7 +71,7 @@ class DecisionEngine {
           cb()
         })
       } else {
-        cb()
+        setImmediate(cb)
       }
     }, cb)
   }
@@ -179,7 +179,7 @@ class DecisionEngine {
     const ledger = this._findOrCreate(peerId)
 
     if (msg.empty) {
-      return cb()
+      return setImmediate(cb)
     }
 
     // If the message was a full wantlist clear the current one
@@ -190,7 +190,7 @@ class DecisionEngine {
     this._processBlocks(msg.blocks, ledger)
 
     if (msg.wantlist.size === 0) {
-      return cb()
+      return setImmediate(cb)
     }
 
     let cancels = []
@@ -219,7 +219,7 @@ class DecisionEngine {
     })
   }
 
-  _addWants (ledger, peerId, entries, cb) {
+  _addWants (ledger, peerId, entries, callback) {
     each(entries, (entry, cb) => {
       // If we already have the block, serve it
       this.blockstore.has(entry.cid, (err, exists) => {
@@ -235,7 +235,7 @@ class DecisionEngine {
       })
     }, () => {
       this._outbox()
-      cb()
+      callback()
     })
   }
 

src/index.js

@@ -4,6 +4,7 @@ const waterfall = require('async/waterfall')
 const reject = require('async/reject')
 const each = require('async/each')
 const series = require('async/series')
+const setImmediate = require('async/setImmediate')
 const map = require('async/map')
 
 const WantManager = require('./want-manager')
@@ -108,7 +109,7 @@ class Bitswap {
       (has, cb) => {
         this._updateReceiveCounters(peerId.toB58String(), block, has)
         if (has) {
-          return cb()
+          return setImmediate(cb)
         }
 
         this._putBlock(block, cb)
@@ -146,7 +147,7 @@ class Bitswap {
   _putBlock (block, callback) {
     this.blockstore.put(block, (err) => {
       if (err) {
-        return callback(err)
+        return setImmediate(() => callback(err))
       }
 
       this.notifications.hasBlock(block)
@@ -310,7 +311,7 @@ class Bitswap {
       (cb) => this.blockstore.has(block.cid, cb),
       (has, cb) => {
         if (has) {
-          return cb()
+          return setImmediate(cb)
         }
 
         this._putBlock(block, cb)
@@ -333,7 +334,7 @@ class Bitswap {
       }, cb),
       (newBlocks, cb) => this.blockstore.putMany(newBlocks, (err) => {
         if (err) {
-          return cb(err)
+          return setImmediate(() => cb(err))
         }
 
         newBlocks.forEach((block) => {
@@ -345,7 +346,7 @@ class Bitswap {
             }
           })
         })
-        cb()
+        setImmediate(cb)
       })
     ], callback)
   }

src/types/message/index.js

@@ -187,7 +187,7 @@ BitswapMessage.deserialize = (raw, callback) => {
   if (decoded.payload.length > 0) {
     return each(decoded.payload, (p, cb) => {
       if (!p.prefix || !p.data) {
-        cb()
+        return setImmediate(cb)
       }
       const values = vd(p.prefix)
       const cidVersion = values[0]
@@ -203,7 +203,7 @@ BitswapMessage.deserialize = (raw, callback) => {
         try {
           cid = new CID(cidVersion, codecName[multicodec.toString('16')], hash)
         } catch (err) {
-          return callback(err)
+          return cb(err)
         }
 
         msg.addBlock(new Block(p.data, cid))