Testing fails in the case of custom node generated from subflow

[kazuhitoyokoi]

I have tried to create test cases for custom nodes generated from a subflow but the test using helper module fails. In this issue, I wrote the example case of the error using a lower-case node created from subflow which contains a function node to use msg.payload.toLowerCase();.

What are the steps to reproduce?

Prepare the following files under the node-red-contrib-example-lower-case directory. And then, execute the npm install and npm test commands.

• test/lower-case_spec.js (the same as official document)

var helper = require("node-red-node-test-helper");
var lowerNode = require("../lower-case.js");

describe('lower-case Node', function () {

  afterEach(function () {
    helper.unload();
  });

  it('should be loaded', function (done) {
    var flow = [{ id: "n1", type: "lower-case", name: "test name" }];
    helper.load(lowerNode, flow, function () {
      var n1 = helper.getNode("n1");
      n1.should.have.property('name', 'test name');
      done();
    });
  });

  it('should make payload lower case', function (done) {
    var flow = [{ id: "n1", type: "lower-case", name: "test name",wires:[["n2"]] },
    { id: "n2", type: "helper" }];
    helper.load(lowerNode, flow, function () {
      var n2 = helper.getNode("n2");
      var n1 = helper.getNode("n1");
      n2.on("input", function (msg) {
        msg.should.have.property('payload', 'uppercase');
        done();
      });
      n1.receive({ payload: "UpperCase" });
    });
  });
});

• package.json

{
  "name": "node-red-contrib-example-lower-case",
  "scripts": {
    "test": "mocha \"test/**/*_spec.js\""
  },
  "node-red": {
    "nodes": {
      "lower-case": "lower-case.js"
    }
  },
  "dependencies": {
    "mocha": "10.1.0",
    "node-red": "3.0.2",
    "node-red-node-test-helper": "0.3.0"
  }
}

• lower-case.js

module.exports = function (RED) {
    const fs = require('fs');
    const path = require("path");
    const file = path.join(__dirname, "subflow.json");
    const text = fs.readFileSync(file);
    const flow = JSON.parse(text);
    RED.nodes.registerSubflow(flow);
}

• subflow.json

{
    "id": "277d18ee2b9e83c9",
    "type": "subflow",
    "name": "lower-case",
    "info": "",
    "category": "",
    "in": [
        {
            "x": 60,
            "y": 80,
            "wires": [
                {
                    "id": "5b296b72cfed90ed"
                }
            ]
        }
    ],
    "out": [
        {
            "x": 340,
            "y": 80,
            "wires": [
                {
                    "id": "5b296b72cfed90ed",
                    "port": 0
                }
            ]
        }
    ],
    "env": [],
    "meta": {
        "module": "node-red-contrib-example-lower-case",
        "type": "lower-case",
        "version": "1.0.0",
        "license": "Apache-2.0"
    },
    "color": "#DDAA99",
    "flow": [
        {
            "id": "5b296b72cfed90ed",
            "type": "function",
            "z": "277d18ee2b9e83c9",
            "name": "function 1",
            "func": "msg.payload = msg.payload.toLowerCase();\nnode.send(msg);",
            "outputs": 1,
            "noerr": 0,
            "initialize": "",
            "finalize": "",
            "libs": [],
            "x": 200,
            "y": 80,
            "wires": [
                []
            ]
        },
        {
            "id": "a10f2fbc4615646b",
            "type": "subflow:277d18ee2b9e83c9",
            "z": "07d1ca735eae83bd",
            "name": "",
            "x": 410,
            "y": 120,
            "wires": [
                [
                    "8c055b9e31ec3702"
                ]
            ]
        }
    ]
}

What happens?

The npm test command outputs the timeout error.

$ npm test

> test
> mocha "test/**/*_spec.js"



  lower-case Node
    1) should be loaded
    2) should make payload lower case


  0 passing (4s)
  2 failing

  1) lower-case Node
       should be loaded:
     Error: Timeout of 2000ms exceeded. For async tests and hooks, ensure "done()" is called; if returning a Promise, ensure it resolves. (/Users/kazuhitoyokoi/Desktop/node-red-contrib-example-lower-case/test/lower-case_spec.js)
      at listOnTimeout (node:internal/timers:564:17)
      at process.processTimers (node:internal/timers:507:7)

  2) lower-case Node
       should make payload lower case:
     Error: Timeout of 2000ms exceeded. For async tests and hooks, ensure "done()" is called; if returning a Promise, ensure it resolves. (/Users/kazuhitoyokoi/Desktop/node-red-contrib-example-lower-case/test/lower-case_spec.js)
      at listOnTimeout (node:internal/timers:564:17)
      at process.processTimers (node:internal/timers:507:7)

What do you expect to happen?

The npm test command passes the test cases. The following is the output of a custom node created by general node development.

$ npm test

> test
> mocha "test/**/*_spec.js"



  lower-case Node
    ✔ should be loaded
    ✔ should make payload lower case


  2 passing (10ms)

Please tell us about your environment:

• Node-RED version: v3.0.2
• Node.js version: v18.7.0
• npm version: v8.15.0
• Platform/OS: macOS Venture 13.0.1, MacBook Air M1, 2020

[naoyaikeda]

I think what makes this project difficult to determine is the common error of timeout errors in a fairly wide range of cases.