chore: apply suggestions from code review

Co-Authored-By: Jacob Heun <[email protected]>

src/topology/README.md

@@ -108,7 +108,7 @@ Add a peer to the topology.
 - `topology.disconnect(peerId)`
 
 **Parameters**
-- `peerId` is the [PeerIid][peer-id] of the peer disconnected.
+- `peerId` is the [PeerId][peer-id] of the peer disconnected.
 
 ###  Multicodec Topology
 
@@ -139,3 +139,5 @@ const toplogy = new MulticodecTopology({
   - `handlers` is an optional `Object` containing the handler called when a peer is connected or disconnected.
     - `onConnect` is a `function` called everytime a peer is connected in the topology context.
     - `onDisconnect` is a `function` called everytime a peer is disconnected in the topology context.
+
+[peer-id]: https://github.com/libp2p/js-peer-id

src/topology/index.js

@@ -26,8 +26,11 @@ class Topology {
     this._onConnect = handlers.onConnect || noop
     this._onDisconnect = handlers.onDisconnect || noop
 
-    // TODO: can this be a set?
-    this.peers = new Map()
+    /**
+     * Set of peers that support the protocol.
+     * @type {Set<string>}
+     */
+    this.peers = new Set()
   }
 
   set registrar (registrar) {

src/topology/multicodec-topology.js

@@ -55,14 +55,14 @@ class MulticodecTopology extends Topology {
 
   /**
    * Update topology.
-   * @param {Array<PeerData>} peerDataIterable
+   * @param {Array<{id: PeerId, multiaddrs: Array<Multiaddr>}>} peerDataIterable
    * @returns {void}
    */
   _updatePeers (peerDataIterable) {
     for (const peerData of peerDataIterable) {
       if (this.multicodecs.filter(multicodec => peerData.protocols.includes(multicodec)).length) {
         // Add the peer regardless of whether or not there is currently a connection
-        this.peers.set(peerData.id.toB58String(), peerData.id)
+        this.peers.add(peerData.id.toB58String())
         // If there is a connection, call _onConnect
         const connection = this._registrar.getConnection(peerData.id)
         connection && this._onConnect(peerData.id, connection)
@@ -80,11 +80,11 @@ class MulticodecTopology extends Topology {
    * @param {Array<string>} props.protocols
    */
   _onProtocolChange ({ peerId, protocols }) {
-    const existingPeer = this.peers.get(peerId.toB58String())
+    const hadPeer = this.peers.has(peerId.toB58String())
     const hasProtocol = protocols.filter(protocol => this.multicodecs.includes(protocol))
 
     // Not supporting the protocol anymore?
-    if (existingPeer && hasProtocol.length === 0) {
+    if (hadPeer && hasProtocol.length === 0) {
       this._onDisconnect(peerId)
     }