ChunkLoadError > Loading chunk cypress-support-file failed

[bene-starzengruber]

Current behavior

After updating from cypress@12.16.0 to cypress@13.6.2, we are seeing this error occasionally on our CI runs.

ChunkLoadError: The following error originated from your test code, not from Cypress.
> Loading chunk cypress-support-file failed.
[(error: http://localhost:8080/__cypress/src/cypress-support-file.js)]
When Cypress detects uncaught errors originating from your test code it will automatically fail the current test.
Cypress could not associate this error to any specific test.
We dynamically generated a new test to display this failure.
[at __webpack_require__.f.j (http://localhost:8080/__cypress/src/runtime.js:272:29)]
[at <unknown> (http://localhost:8080/__cypress/src/runtime.js:126:40)]
at Array.reduce (<anonymous>)
[at __webpack_require__.e (http://localhost:8080/__cypress/src/runtime.js:125:67)]
[at Object.load (http://localhost:8080/__cypress/src/cypress-entry.js:33:192)]
[at <unknown> (http://localhost:8080/__cypress/runner/cypress_runner.js:110819:21)]
[at tryCatcher (http://localhost:8080/__cypress/runner/cypress_runner.js:1807:23)]
[at Object.gotValue (http://localhost:8080/__cypress/runner/cypress_runner.js:6476:18)]
[at Object.gotAccum (http://localhost:8080/__cypress/runner/cypress_runner.js:6465:25)]
[at Object.tryCatcher (http://localhost:8080/__cypress/runner/cypress_runner.js:1807:23)]

Unfortunately it is not reproducable locally, so I can not give you a repository to check.
I know that this might make it hard to investigate but maybe somebody already fell over the same issue or others are experiencing it as well.

The test fails around 30% of the time.

Desired behavior

No response

Test code to reproduce

no reproduction repository

Cypress Version

13.6.2

Node version

18.19.0

Operating System

Ubuntu 22.04.3

Debug Logs

No response

Other

No response

[jennifer-shehane]

We made an update from webpack 4 to webpack 5 in 12.17.4, I wonder if it has anything to do with that upgrade. https://docs.cypress.io/guides/references/changelog#12-17-4

[cubanx]

We are getting the same error also intermittently. I don't think we had it as far back as 12.17.4 but I can't say that for certain.

It only seems to happen toward the end of our Component Test runs. We have 1500+ component tests that we are running.

The following error originated from your test code, not from Cypress.

  > Loading chunk cypress-support-file failed.
(error: http://localhost:8080/__cypress/src/cypress-support-file.js)

When Cypress detects uncaught errors originating from your test code it will automatically fail the current test.

Cypress could not associate this error to any specific test.

We dynamically generated a new test to display this failure.
ChunkLoadError: The following error originated from your test code, not from Cypress.
  > Loading chunk cypress-support-file failed.
(error: http://localhost:8080/__cypress/src/cypress-support-file.js
When Cypress detects uncaught errors originating from your test code it will automatically fail the current test.
Cypress could not associate this error to any specific test.
We dynamically generated a new test to display this failure.
    at __webpack_require__.f.j (http://localhost:8080/__cypress/src/main.js:8702:29
    at <unknown> (http://localhost:8080/__cypress/src/main.js:8552:40
    at Array.reduce (<anonymous>)
    at __webpack_require__.e (http://localhost:8080/__cypress/src/main.js:8551:67
    at Object.load (http://localhost:8080/__cypress/src/main.js:1510:582
    at <unknown> (http://localhost:8080/__cypress/runner/cypress_runner.js:110819:21
    at tryCatcher (http://localhost:8080/__cypress/runner/cypress_runner.js:1807:23
    at Object.gotValue (http://localhost:8080/__cypress/runner/cypress_runner.js:6476:18
    at Object.gotAccum (http://localhost:8080/__cypress/runner/cypress_runner.js:6465:25
    at Object.tryCatcher (http://localhost:8080/__cypress/runner/cypress_runner.js:1807:23
[Open in build log](https://teamcity.haivision.com/buildConfiguration/CineNet4x_Projects_CypressComponents/690401?hideProblemsFromDependencies=false&expandBuildTestsSection=true&hideTestsFromDependencies=false&expandBuildChangesSection=true&showLog=690401_2000000247_2000000247&logFilter=debug)

[werge2121]

Same for us too

[amir1218]

We have been running into this sporadically when Component testing after migrating from CY 12.x to 13.6.2. Similarly to cases above, it happens towards the end of running a batch of suites (files) together.

Resorted to running cypress with DEBUG='cypress:*'. This is an instance of a crash:

 cypress: server: reporter got mocha event 'test'
with args: [u {
    title: 'An uncaught error was detected outside of a test',
    fn: [Function: o] {
        toString: [Function(anonymous)]
    },
    body: '() => {\n        throw err;\n      }',
    async: undefined,
    sync: undefined,
    _timeout: 2000,
    _slow: 250,
    _enableTimeouts: true,
    timedOut: undefined,
    _retries: -1,
    _currentRetry: 0,
    pending: false,
    type: 'test',
    duration: undefined,
    state: 'skipped',
    parent: p {
        title: '',
        ctx: {},
        suites: [],
        tests: [Array],
        pending: false,
        _beforeEach: [],
        _beforeAll: [],
        _afterEach: [],
        _afterAll: [],
        root: true,
        _timeout: 2000,
        _enableTimeouts: true,
        _slow: 250,
        _bail: false,
        _retries: -1,
        _onlyTests: [],
        _onlySuites: [],
        delayed: false,
        _events: [Object: null prototype],
        _eventsCount: 1,
        file: 'VALID_PATH_TO_FILE_DEDACTED',
        id: 'r1',
        type: 'suite'
    },
    id: 'r2',
    _testConfig: {
        testConfigList: [],
        unverifiedTestConfig: {}
    },
    order: 1,
    invocationDetails: {
        function: 'Object.getInvocationDetails',
        fileUrl: 'http://localhost:8080/__cypress/runner/cypress_runner.js',
        originalFile: 'http://localhost:8080/__cypress/runner/cypress_runner.js',
        line: 97377,
        column: 17,
        whitespace: '    ',
        stack: 'Error\n' + '    at Object.getInvocationDetails 
(http://localhost:8080/__cypress/runner/cypress_runner.js:97377:17)\n' + '    at Suite.addTest 
(http://localhost:8080/__cypress/runner/cypress_runner.js:145737:85)\n' + '    at Object.createRootTest 
(http://localhost:8080/__cypress/runner/cypress_runner.js:145872:21)\n' + '    at Object.normalizeAll 
(http://localhost:8080/__cypress/runner/cypress_runner.js:163115:17)\n' + '    at CDPBrowserSocket.<anonymous> 
(http://localhost:8080/__/assets/index-caf2649c.js:146264:46)\n' + '    at CDPBrowserSocket.on2 
(http://localhost:8080/__/assets/index-caf2649c.js:34575:11)\n' + '    at Emitter2.emit 
(http://localhost:8080/__/assets/index-caf2649c.js:34616:24)\n' + '    at http://localhost:8080/__/assets/index-caf2649c.js:37709:15'

    }
}] + 9 ms

There is a lot in the logs that makes it hard to share but please do let us know if we should be looking for or can share anything useful to help unraveling this.

[cubanx]

Does anyone know of a way to suppress this error until we can get a resolution?

[rbecheras]

We have a very similar issue with another file: node_modules_core-js_modules_es_array_concat_js-node_modules_babel_runtime_helpers_esm_define-ec4858

1) An uncaught error was detected outside of a test

  0 passing (433ms)
  1 failing

  1) An uncaught error was detected outside of a test:
     ChunkLoadError: The following error originated from your test code, not from Cypress.

  > Loading chunk node_modules_core-js_modules_es_array_concat_js-node_modules_babel_runtime_helpers_esm_define-ec4858 failed.
(error: http://localhost:8080/__cypress/src/node_modules_core-js_modules_es_array_concat_js-node_modules_babel_runtime_helpers_esm_define-ec4858.js)

When Cypress detects uncaught errors originating from your test code it will automatically fail the current test.

Cypress could not associate this error to any specific test.

It makes our test suite pass sometimes but fail randomly and frequently, on a component or another, randomly.

[benpatterson]

I'm leaving behind some notes after digging into this further.

We are experiencing this error on ~9% of our component test builds. (I can't remember offhand how many tests that entails.)

Indeed error messages above are consistent with what we see, here's an excerpt (with a slight edit on chunk name tbh):

  1) An uncaught error was detected outside of a test:
     ChunkLoadError: The following error originated from your test code, not from Cypress.

  > Loading chunk name1-name2-file~spec-11~spec-14~spec-15~spec-17~spec-22~spec-23~spec-25~spec-27~spec-28~43d59dbf failed.

It includes the localhost path as well on the next line (which I left out here).

Noteworthy...going up a few lines in the build, we are seeing something like this (I changed more file names out of caution):

  Running:  dir/myComponentSpec.spec.tsx                                                  
  Estimated: 1 second


ℹ ｢wdm｣: Compiling...
  (Attempt 1 of 3) An uncaught error was detected outside of a test
ℹ ｢wdm｣: wait until bundle finished: /<root+directory>/related-file~spec-34.js
ℹ ｢wdm｣: wait until bundle finished: /<root+directory>/related-file.js
  (Attempt 2 of 3) An uncaught error was detected outside of a test
  1) An uncaught error was detected outside of a test

It appears to me that the ChunkLoadError occurs because the next test is running before webpack compilation is completed on the devserver. I think this includes related CSS compilations, but honestly I don't know if that's all the time or a subset of examples.

Ultimately I'm convinced the next test needs to wait until compilation completes and the devserver has updated the cache. I attempted to set devserver settings around hot reload, etc, but those didn't work -- likely because the test is still trying to serve the page and is not waiting for the devserver to signal it's up to date.

When it comes to waiting for compilation to complete, we do have logic around this in CypressCTWebpackPlugin in this function. As-written, it's awaiting specs, and this is why I'm wondering if we need something to wait for related assets, too. Regardless, I think we need a way of ensuring all compilation completes, including any styling, before proceeding to the next test.

There had been a previous PR that leveraged the webpack devserver's index HTML file, which I believe would yield the result I'm thinking of (change here). That PR was intended to fix a situation specific to MacOS version, but I'm optimistic it could resolve the ChunkLoadError. The PR was merged but the code in the file today is older than the PR, so I don't know if it was rolled back at a later time.

[hogatejon]

Just commenting to say I am also experiencing this issue. Have traced it down to being introduced by 12.17.4, any version below this seems to be completely fine on our CI runs.

[jennifer-shehane]

Found this in our own tests: https://cloud.cypress.io/projects/ypt4pf/runs/53776/overview/c7135bc3-5fcb-4555-8497-c7b93658a628?roarHideRunsWithDiffGroupsAndTags=1

[jennifer-shehane]

We're spiking into this to see if we can find what's causing this.