JS Testing Feature: Multiple return values from interaction

[srinjoyc]

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Description (Problem Statement)

The JS Testing Framework has two functions: sendTransaction and executeScript that currently return a single result from their execution. It does not have a good way of handling errors that should be caught and processed. This can cause issues with multiple interactions called in succession.

Experience Required

• Great proficiency with JavaScript
• Good understanding of Cadence and Flow JS SDK

Minimum Feature Set (Acceptance Criteria)

• Catch error inside interaction code and always return tuple [result, error].

• This should make it easier to assert the result of interaction using jest and other libraries.

• Flow Cadut interactions are already implemented in such a way (refer to this piece of code as an example - https://github.com/onflow/flow-cadut/blob/main/src/interactions.js#L55-L63) so it's mostly a refactoring task.

Extension Feature Set (Optional)

Parse error message and provide an error in form of an object, containing at least errorCode, message. If possible extract more information and format it in a human-readable and usable way.

Milestone Requirements

1. Meet the minimum feature set and optionally the extension.

Software Requirements

Maintainability

Code should be written with best practices in mind.

Other Requirements

Documentation

• Documentation should be updated according to the changes made.

Code standards or guidelines

• Follow the general contribution guidelines.

Judging Criteria

• For all projects, technical & high-level judging criteria apply.

Resources

• General Resource Guide
• Flow JS Testing
  • Repository
  • Flow Cadut

[MaxStalker]

Hey, Flow Surfer!
My name is Max. I am core member of Developer Experience team and I will be your Point-of-Contact for this task.
If you stumble into any challenges with this task, feel free to contact me via replies to this issue or over Flow Discord (my handle is MaxStarka#5714).

Looking forward to work with you! :)

[OmarMalik]

Hey Max, I want to make sure I'm understanding this correctly.

Since we are changing the return types of executeScript and executeTransaction in the flow-js-testing library, won't that break any existing code that uses these functions? Not sure how to get around this.

For example, I'm imagining the intended refactor for executeScript is the following:

export const executeScript = async (...props) => {
    try {
        const extractor = extractParameters("script");
        const { code, args } = await extractor(props);
        
        const ix = [fcl.script(code)];
        // add arguments if any
        if (args) {
          ix.push(fcl.args(resolveArguments(args, code)));
        }
        const response = await fcl.send(ix);
        const result = await fcl.decode(response);
        [result, null]
    } catch (e) {
        return [null, e]
    }
}

Am I on the right track here?

[MaxStalker]

@OmarMalik that is correct - this will be breaking change if your code previously wasn't using Jest helper methods.

There are 3 ways to go:

• use fcl.config param to decide how returned value shall look and whether to catch error or not
• introduce the breaking change with new release and make it clear how developer can refactor it
• mix two aforementioned solutions by introducing new fcl.configparam in next release and deprecate it and old way of doing things in following

Your call ;)

[MaxStalker]

Hey, @OmarMalik are you still working on this issue? :)

[hichana]

@OmarMalik if you are still working on this FLIP issue, can you let us know? If not, and if ok with @MaxStalker I'm hoping to do this one in the time that remains with @J00LZ. Thanks

[hichana]

TeamExponential members:
https://github.com/justjoolz
https://github.com/hichana
We would like to take on this flip if ok @MaxStalker.

[MaxStalker]

Green light, @hichana !

[hichana]

Hello @MaxStalker, we have made our final submission for this FLIP fest issue: #91
Looking forward to your feedback and/or approval. Thank you

[MaxStalker]

🎉 Milestone Achieved! 🎉

Thank you for your submission and participation!