Unhandled Promise Rejection on 'sendRequest'

[gabmontes]

When .send()'ing a contract method, web3 creates the handling logic, returns a promiEvent and finally executes the call at:

https://github.com/ethereum/web3.js/blob/0d54d94e637832abf97834e4fc444fbff87f874b/packages/web3-core-method/src/index.js#L581

Inside sendRequest, there is a call to signTransaction:

https://github.com/ethereum/web3.js/blob/0d54d94e637832abf97834e4fc444fbff87f874b/packages/web3-core-method/src/index.js#L536

If for any reason the signing fails, i.e. the net API is not enabled in the underlying node, signTransaction returns a failed promise that will be lost as the original sendRequest call does handle it (does not act on defer or defer.eventEmitter).

The result is an Unhandled Promise Rejection error and the web3 user code client hangs given the promiEvent does never emit even an error event.

@nivida I'm happy to contribute with a fix/PR. Just wondering if you or @frozeman have any thoughts on the better way to handle this.

Issue #1220 is possibly related or similar to this.

[nivida]

This will be fixed with the PR #2000

[nivida]

This is fixed since beta.38.