AI Test Fix: Jest & ESM Configuration
Hey guys! Let's dive into a bit of a head-scratcher we've run into with our AI tests. Basically, we're seeing some issues where the way our Jest testing setup and our ESM (ECMAScript Modules) configurations aren't quite playing nice together. It's causing some test failures, but thankfully, it's not affecting how our AI actually runs in the real world. Think of it as a minor bump in the road for our testing process.
The Core of the Problem: Jest, ESM, and import.meta.url
So, what's the deal? Well, the main culprit seems to be a conflict between how Jest, which is our JavaScript testing framework, handles ESM, and the use of import.meta.url
within our AI code. This import.meta.url
is a handy JavaScript feature that gives us the file path of the current module. Our problem is that Jest, by default, doesn't always play well with this feature, especially when it comes to the module system being used.
The import.meta.url
Saga
The first error we're seeing is the dreaded TS1343 error. This pops up in our moveSelection.ts
file and basically says, "Hey, import.meta
isn't allowed here unless you're using a specific module system like node16
or nodenext
." Jest, or rather, the way we've configured it, isn't quite aligned with this requirement for this specific file, causing the test to fail. Imagine trying to use a special tool without the right adapter; it just won't work!
ESM Parse Errors: When Modules Clash
Next up, we've got some ESM parse errors. This happens when our tests try to load files from our core
directory, which in turn tries to use modules from our AI's dist
folder. The dist
folder contains the built, or compiled, version of our AI code. Since the dist
folder is designed to work with ESM, and Jest might not be perfectly configured to handle ESM from this location, we get a "Cannot use import statement outside a module" error. This is because Jest might not be recognizing the ESM syntax in the dist
files correctly. It's like trying to read a book in a language you don't understand; the words are there, but they don't make sense!
How to Reproduce the Issue
If you want to see this firsthand, here's how you can make it happen:
- From the root of our repository, run
npm run test:ai
. This command kicks off our AI test suite.
When you do this, you should see the failures we've described above. Specifically, you'll likely see the TS1343
error and the ESM parse error. If you're curious about the specifics of the files involved, take a look at the "Files/Tests implicated" section in the original report. This section lists the exact files and tests that are causing trouble.
Digging Deeper: The Failing Tests
Let's take a closer look at the tests that are failing. We've got a few key files that are causing the problems:
packages/ai/src/moveSelection.ts
: This is where theimport.meta.url
is causing problems.packages/ai/src/ extbf{tests} extbf{/index.test.ts}
: This test file is likely importing modules that are causing the ESM parse errors.packages/ai/src/ extbf{tests} extbf{/gbg-bot-failure.test.ts}
: Another test that's probably running into the same ESM issues.packages/ai/src/ extbf{tests} extbf{/bar-reentry-dice-bug.test.ts}
: This test pulls in code from thecore
directory, which then tries to use ESM modules from thedist
directory of our AI. This is where we see the ESM parse error.
These tests are crucial for making sure our AI works correctly. It is a good thing that we are aware of them and can correct the errors.
Proposed Fixes: A Path Forward
We've got a few ideas on how to fix this, and we can choose the one that makes the most sense. Here's a rundown of the proposed fixes:
Jest/ts-jest Configuration Tweaks
- Module Target Adjustment: We could configure Jest and
ts-jest
(which helps Jest run TypeScript code) to use thenode16
ornodenext
module target for our tests. This would allow the use ofimport.meta
without throwing an error. This is like telling Jest, "Hey, understand this new way of writing code!" It's usually the best way to solve this type of error. - Conditional or Alternate Path Resolution: Another option is to change how we use
import.meta.url
in the code. We could use a conditional check to see if we're running in a testing environment and use a different method to get the file path. This is a bit of a workaround, but it might be necessary if we can't easily change the Jest configuration.
ESM Interop Strategies
- Source Imports or Mocking: Instead of importing from the
dist
folder in our tests, we could import directly from the source code. This would bypass the ESM issues since the source code is likely not compiled in the same way. Or, we could mock the affected modules so that we don't need to load the actual code at all. This is like pretending a piece of code is there and ensuring it doesn't cause problems in your tests. - Transforming
dist
with Jest: We could configure Jest to transform the ESM in thedist
folder. This means Jest would convert the ESM code into something it can understand. This can be complex, and might not always be worth the effort. - Native ESM Mode for Jest: The most direct approach might be to switch Jest to native ESM mode in this package. This would tell Jest to use ESM directly. This would need us to change the whole architecture.
Why Low Priority?
Because all of these errors happen only in tests, and not in production code. The AI still works correctly. We can correct it when we have the time.
What to Expect after the Fix
Our main goal is to get the npm run test:ai
command to run without any errors, and make our tests green. We're also making sure that we don't change how the AI works in our real application. The fix should only affect the tests and should keep the ESM build for packages. We want to adjust the test configuration, or the test imports or mocks, to resolve these issues.
Conclusion
So, there you have it, guys. We've got a bit of a configuration mismatch between Jest and our ESM setup, causing some test failures. But don't worry, the core AI functionality is unaffected. We've got a few potential solutions to explore, and we'll get these tests running smoothly again soon. It's all about making sure our AI is as reliable as possible! By the way, the regression test passes, which is good!