parallelize FFI language binding tests in contrib/test.sh

[caarloshenriq]

Parallelizes the language binding tests in payjoin-ffi/contrib/test.sh
instead of running them sequentially.

This is a follow-up to a comment by @spacebear21 on #1492.

AI Assistance: Used Claude to help implement the parallelization approach.

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[coveralls]

Coverage Report for CI Build 25125404880

Coverage remained the same at 84.989%

Details

• Coverage remained the same as the base build.
• Patch coverage: No coverable lines changed in this PR.
• No coverage regressions found.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

No coverage regressions found.

---

Coverage Stats

Relevant Lines:	13437
Covered Lines:	11420
Line Coverage:	84.99%
Coverage Strength:	398.83 hits per line

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💛 - Coveralls

[benalleng]

Added a commit to fix the execution permissions which were a problem in JS too.

TACK 8b64a29

[benalleng]

So I have it in writing I did have to clean the ~/payjoin-ffi/dart/native/Cargo.lock as it was suffering from a failure due to the stuff from #1502. Maybe it would be useful to have a script to just clean this deep nested lockfile every time we run tests assuming it doesn't get touched very often.

[caarloshenriq]

Maybe it would be useful to have a script to just clean this

added a script in dart/contrib/test.sh to clean this.

[spacebear21]

cACK

I'm afk this week so may not get around to testing this but ideally would like someone to validate and post the output of:

• all succeeds
• fails for one specific language
• fails for all languages

[caarloshenriq]

would like someone to validate and post the output

Here are the three scenarios you requested. I've trimmed the outputs for readability as they were quite verbose:

1. All succeeds (exit code: 0):

== Running dart tests...
00:21 +17: All tests passed!

== Running C# tests...
Payjoin.Tests - Payjoin.Tests.dll
Test run for Payjoin.Tests.dll (.NETCoreApp,Version=v8.0)

== Running tests... (python)
Ran 17 tests in 13.993s OK

== Running JavaScript tests...
npm run ubrn:web && npm run compile && npm run copy-wasm && npm run fix-imports
✓ All done

$ echo $? - 0

2. Fails for one specific language — javascript (exit code: 1):

00:20 +17: All tests passed! (dart)
Ran 17 tests in 11.809s OK (python)

error: failed to select a version for `bitcoin-units`
...failed to select a version for `bitcoin-units` which could resolve this conflict
Error: Failed to run command (javascript)

$ echo $? - 1

3. Fails for all languages (exit code: 1):

running 0 tests
test result: ok. 0 passed (rust)

dart: exit 1
javascript: exit 1
python: exit 1
csharp: exit 1

$ echo $? - 1

In all failure scenarios the script correctly returns exit code 1, and in scenario 2 the passing languages continued running in parallel without being blocked by the failing one.