fixed the case when the client is disconnected while tests were running

Author: gdavidkov

packages/server/fixtures/client.js.js

@@ -0,0 +1,10 @@
+const { Client } = require("mocha-remote-client");
+
+const client = new Client({
+    autoConnect: true,
+    tests: () => {
+        it("should reject", (done) => {
+            done(new Error("This should not happen"));
+        });
+    }
+});

packages/server/fixtures/clientVeryLongRun.js

@@ -0,0 +1,13 @@
+const { Client } = require("mocha-remote-client");
+
+const client = new Client({
+    autoConnect: true,
+    timeout: 1000000,
+    tests: () => {
+        it("endless", (done) => {
+            setTimeout(() => {
+                done();
+            }, 1000000);
+        });
+    }
+});

packages/server/src/Server.test.ts

@@ -1,6 +1,8 @@
 import { expect } from "chai";
 import { WebSocket } from "ws";
 import flatted from "flatted";
+import { ChildProcess, fork } from "child_process";
+import { resolve } from "path";
 
 import { Server } from "./Server";
 
@@ -91,4 +93,85 @@ describe("Mocha Remote Server", () => {
       }
     }
   });
+
+  const startRemoteClient = (script: string, server: Server) => {
+    return new Promise<ChildProcess>((resolve) => {
+      const clientProcess = fork(script, { stdio: "inherit" });
+      const onConnection = () => {
+        cleanup();
+        resolve(clientProcess);
+      };
+      const cleanup = () => {
+        server.off("connection", onConnection);
+      }
+      server.on("connection", onConnection);
+    });
+  };
+
+  const stopRemoteClient = (childClientProcess: ChildProcess) => {
+    return new Promise<void>((resolve, reject) => {
+      childClientProcess.once("exit", () => {
+        resolve();
+      });
+      childClientProcess.kill();
+    });
+  };
+
+  const runTests = (server: Server) => {
+    return new Promise<number>((resolve, reject) => {
+      server.run((failures) => {
+        resolve(failures);
+      });
+    });
+  };
+
+  it("should be able to start again, when the server is stopped during a run", async () => {
+    // Create and start the server
+    const server = new Server({
+      port: 8090,
+      reporter: "base",
+      autoRun: false,
+    });
+
+    await server.start();
+
+    const clientThatHangsScriptPath = resolve(__dirname, "../fixtures/clientVeryLongRun.js");
+    const childClientProcess = await startRemoteClient(clientThatHangsScriptPath, server);
+
+    server.run(() => {
+      //
+    });
+
+    await server.stop();
+    await server.start();
+    
+    await server.stop();
+    await stopRemoteClient(childClientProcess);
+  });
+
+  it("should be able to start again, on client disconnection while running", async () => {
+    // Create and start the server
+    const server = new Server({
+      port: 8090,
+      reporter: "base",
+      autoRun: false,
+    });
+
+    await server.start();
+
+    const clientThatHangsScriptPath = resolve(__dirname, "../fixtures/clientVeryLongRun.js");
+    const childClientProcess = await startRemoteClient(clientThatHangsScriptPath, server);
+
+    const results = await Promise.all([runTests(server), stopRemoteClient(childClientProcess)]);
+    const failures = results[0];
+    expect(failures).to.equal(0);
+
+    const clientScriptPath = resolve(__dirname, "../fixtures/client.js");
+    const remoteClientProcess = await startRemoteClient(clientScriptPath, server);
+
+    const result = await runTests(server);
+    expect(result).to.equal(1);
+    await server.stop();
+    await stopRemoteClient(remoteClientProcess);
+  });
 });

packages/server/src/Server.ts

@@ -151,7 +151,6 @@ export class Server extends ServerEventEmitter {
         this.wss.close(err => {
           // Delete the runner to allow another run
           delete this.runner;
-
           // Forget about the server
           delete this.wss;
           // Reject or resolve the promise
@@ -324,6 +323,11 @@ export class Server extends ServerEventEmitter {
     // Check that the protocol matches
     const expectedProtocol = `mocha-remote-${this.config.id}`;
     ws.on("close", (code, reason) => {
+      if(this.runner) {
+        this.debug("Client disconnected while tests were running");
+        this.runner.emit("end");
+        delete this.runner;
+      }
       this.emit("disconnection", ws, code, reason.toString());
     });
     // Signal that a client has connected