Truffle: Uncaught TypeError: Cannot read property 'constructor' of undefined

[danielfebrero]

Issue

Comparing a bool from a Structure return error when combined with an Event.

Cannot read property 'constructor' of undefined

when running Truffle test

Steps to Reproduce

Contract

Contract Bug {
    One demo;

    event Ramdom(String);

    struct One {
        bool active;
        address user;
    }

    function init() {
        demo = One({active: false, address: 0x0});
    }

    function isActive() returns (bool) {
        Ramdom("buggy");
        // Option 1
        if(demo.active == true){
            return true;
        }else { return false; }

        // Option 2
        if(demo.address == address(0)){
            return false;
        }else { return true; }
    }
}

Test:

it('is a demo test', () => {
        return Bug.init()
            .then(txObject => Bug.isActive())
      })

Expected Behavior

Return True or False when the Structure.bool is true or false.

Actual Results

When using Option 1, the bug happens;
When using Option 2, it works fine;

Environment

• Operating System: macOs
• Truffle version: 3.2.8
• Ethereum client: testrpc
• Solidity: 0.4.11
• node version: 6.7.0
• npm version: 4.0.3

[izqui]

Naming the event parameter in solidity solved this issue for us.

Try replacing event Random(string) for event Random(string random)

[danielfebrero]

Interesting, thank you, I will try it!

[mikeshultz]

Just ran into this. This is a very odd bug. Is not naming event params technically a bad pattern in Solidity code?

[tomasienrbc]

Had this problem as well - I share Mike's question, what's the pressing need to name event attributes? I'll assume it's the right design decision going forward but I didn't know that.

[alexaltair]

I ran into this problem also. I defined an event and did not name the address parameter, which resulted in Uncaught TypeError: Cannot read property 'constructor' of undefined. If this issue hadn't come up in google I never would have figure it out.

[roderik]

Indeed, same issue for me. I like to use event Debug(bool, bool, bool) for example to debug values in my smart contracts. event Debug(bool a, bool b, bool c) works like a charm

[weslienlive]

Adding the name worked for me too.

[bellaj]

I confirm i can reproduce the same error
and it's solved as stated by other developers by adding arguments names like following :
eventX(bool b, address a...)

[john-osullivan]

Another confirmation for the pile -- saw the same bug, fixed it by naming the event params.

[stale[bot]]

Thank you for raising this issue! It has been automatically marked as stale because it has not had recent activity. It will be closed in 7 days if no further activity occurs. If you would like to keep this issue open, please respond with information about the current state of this problem.

[stale[bot]]

There has been no new activity on this issue since it was marked as stale 7 days ago, so it is being automatically closed. If you'd like help with this or a different problem, please open a new issue. Thanks!

[l-henri]

Same issue here

[adibas03]

@l-henri check at the comment above
https://github.com/trufflesuite/truffle/issues/494#issuecomment-316044753