RFC: Performance after upgrading from 25.2.1 to 25.3.0

[MykytaKryvenko]

Issue :

25.3.0 version is extremely slow compared to 25.2.x.
E.g. my previous test runs were 17s, and 135s after update.

[ahnpnl]

can you please provide more information ? Do you run with or without cache ? Did you clear cache after upgrading to 25.3.0 ?

[MykytaKryvenko]

I tried to run jest with --clearCache, did not help.

[ahnpnl]

from what I can see is, before upgrading probably your tests ran with cache. After upgrading, old cache becomes invalid so tests will need to cache again. That's why you saw a big difference. Several steps that you can help us to verify is:

• Clear cache
• Run tests with --no-cache for 25.2.1
• Clear cache again
• Run tests with --no-cache for 25.3.0

If the amount of time tests take is the same for these above steps, it means no downgrade

[MykytaKryvenko]

Thank you for the suggestion, but it did not help as well :(
After all steps and running with no-cache it takes ~270s to finish.

[ahnpnl]

Hmm I don’t see any issues on my side. Also confirmed from #1450 (comment)

[ahnpnl]

Any chances to have your repo to try out ?

[MykytaKryvenko]

Unfortunately no.
We have pinned version for now. Maybe someone else will face this issue too.

[bmesuere]

Maybe it's related but moving to 25.3.0, it seems that a lot more files are getting compiled. We use this in a rails project and are now getting a bunch of errors like error TS5055: Cannot write file '/<<path>>/config/webpack/development.js' because it would overwrite input file. which suggests it now handles every js file in repository.

[ahnpnl]

Maybe it's related but moving to 25.3.0, it seems that a lot more files are getting compiled. We use this in a rails project and are now getting a bunch of errors like error TS5055: Cannot write file '/<<path>>/config/webpack/development.js' because it would overwrite input file. which suggests it now handles every js file in repository.

thanks for your feedback. Do you use allowJs in your repo ?

[bmesuere]

yes, I do. After checking the other issues, I think #1472 will probably resolve the error for me.

[ahnpnl]

Thanks. Probably the issue is bigger than just the fix #1472 as you mentioned that there are more files getting compile. That is a useful hint to solve this issue.

Up til now, imo #1472 is just a workaround and there should be a proper fix.

[MykytaKryvenko]

I want to add that we are using allowJs too, without it compilation fails for 25.3.0, but works for 25.2.1

[ahnpnl]

if you guys don't mind, please test with this tgz file. I just made an attempt to fix it but not so sure.

[LasaleFamine]

I'm hitting the same problem just after the upgrade to 25.3.0 and I have a lot of:
Cannot write file 'path/to/file.js' because it would overwrite input file

I'm using allowJs too. Also if I add the outDir tests will work but they are extremely slow.

[ahnpnl]

hi guys, please test again this branch https://github.com/ahnpnl/ts-jest/tree/fix-diagnostics to see if it helps

[LasaleFamine]

Seems like I cannot install it from GitHub with yarn add --dev -W https://github.com/ahnpnl/ts-jest#fix-diagnostics. Here is the error:

$ npm run build
npm WARN lifecycle The node binary used for scripts is /var/folders/sl/w6pt8g5j2b332rk_776pwdbc0000gn/T/yarn--1585747708265-0.824303838895643/node but npm is using /Users/occhipintia/.nvm/versions/node/v10.13.0/bin/node itself. Use the `--scripts-prepend-node-path` option to include the path for the node binary npm was executed with.

> ts-jest@25.3.0 prebuild /Users/occhipintia/Library/Caches/Yarn/v6/.tmp/5c55e78258b66b7b689625fcb8d6906e.dd8b2e4e117869706228fab75b0ba68f183752f0.prepare
> node scripts/clean-dist.js


> ts-jest@25.3.0 build /Users/occhipintia/Library/Caches/Yarn/v6/.tmp/5c55e78258b66b7b689625fcb8d6906e.dd8b2e4e117869706228fab75b0ba68f183752f0.prepare
> tsc -p tsconfig.build.json

src/cli/config/migrate.ts:3:32 - error TS2497: This module can only be referenced with ECMAScript imports/exports by turning on the 'esModuleInterop' flag and referencing its default export.

3 import * as stringifyJson from 'fast-json-stable-stringify'
                                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~

NOTE: I'm in a monorepo.

[ahnpnl]

Here is the zip of the tgz file.
ts-jest-25.3.1.tgz.zip

[LasaleFamine]

Alright, seems like we have some good news: installed the new version from your zip I can run the tests without the Cannot write file 'path/to/file.js' because it would overwrite input file error.

Also I have notice the slowness just the first time I run it, but the second run, using the cache, it goes down to 5 seconds running all tests. So I can say the last fix solved the problem. Looking forward for the 25.3.1 release!

It is also worth to say that I haven't changed my tsconfig.json to make this work again.

Thanks for your time @ahnpnl!

[ahnpnl]

thanks a lot for helping us !. I will make a PR shortly 👍

[MykytaKryvenko]

@ahnpnl, thanks a lot for the fix! Do you know when it will be released?

[ahnpnl]

we are having a bit issue with publishing today, but will be solved shortly. Stay tune :)

Updated: 25.3.1 is out

[kirillgroshkov]

Yes, we also experienced perf degradation. Will test with 25.3.1