Add subscription tests for disconnect & setProvider (#3190)

test/eth.subscribe.ganache.js

@@ -1,14 +1,15 @@
 const assert = require('assert');
 const ganache = require('ganache-cli');
 const pify = require('pify');
-const Web3 = require('./helpers/test.utils').getWeb3();
+const { getWeb3, waitSeconds } = require('./helpers/test.utils');
 
 describe('subscription connect/reconnect', function () {
     let server;
     let web3;
     let accounts;
     let subscription;
     const port = 8545;
+    const Web3 = getWeb3();
 
     beforeEach(async function () {
         server = ganache.server({port: port, blockTime: 1});
@@ -100,6 +101,61 @@ describe('subscription connect/reconnect', function () {
         }, 500);
     });
 
+    // The ganache unit tests are erroring under similar conditions -
+    it('does not error when client closes after disconnect', async function(){
+        this.timeout(7000);
+
+        return new Promise(async function(resolve, reject) {
+            web3.eth
+                .subscribe('newBlockHeaders')
+                .once("error", function (err) {
+                    reject(new Error('Should not hear an error '));
+                });
+
+            // Let a couple blocks mine..
+            await waitSeconds(2)
+            web3.currentProvider.disconnect();
+
+            // This delay seems to be required (on Travis).
+            await waitSeconds(1);
+
+            await pify(server.close)();
+
+            await waitSeconds(1)
+            resolve();
+        });
+    });
+
+    // Verify subscription cleanup on setProvider
+    it('does not hear old subscriptions after setting a new provider', async function(){
+        this.timeout(7000);
+        let counter = 0;
+
+        return new Promise(async function(resolve, reject) {
+            web3.eth
+                .subscribe('newBlockHeaders')
+                .on("data", function (_) {
+                    counter++;
+                });
+
+            // Let a couple blocks mine..
+            await waitSeconds(2)
+            assert(counter >= 1);
+
+            // Connect to a different client;
+            const newServer = ganache.server({port: 8777, blockTime: 1});
+            await pify(newServer.listen)(8777);
+
+            const finalCount = counter;
+            web3.setProvider(new Web3.providers.WebsocketProvider('ws://localhost:8777'));
+
+            await waitSeconds(2);
+            assert.equal(counter, finalCount);
+            await pify(newServer.close)();
+            resolve();
+        });
+    })
+
     it('allows a subscription which does not exist', function () {
         web3.eth.subscribe('subscription-does-not-exists');
     });

test/helpers/test.utils.js

@@ -51,12 +51,17 @@ var getWebsocketPort = function(){
     return ( process.env.GANACHE || global.window ) ?  8545 : 8546;
 }
 
+// Delay
+var waitSeconds = async function(seconds = 0){
+    return new Promise(resolve => setTimeout(() => resolve(), seconds * 1000))
+}
+
 module.exports = {
     methodExists: methodExists,
     propertyExists: propertyExists,
     mine: mine,
     extractReceipt: extractReceipt,
     getWeb3: getWeb3,
     getWebsocketPort: getWebsocketPort,
+    waitSeconds: waitSeconds
 };
-