Eslint-plugin-react: Add configuration for no-did-update-set-state to allow usage inside condition

[dcocchia]

As @gaearon has mentioned here and other places, using setState inside componenDidUpdate is acceptable, so long as it's within a conditional check.

Does it seem reasonable to allow a configuration option for this rule to allow setState usage within componenDidUpdate, so long as it's within a conditional check of some kind?

For example, this would pass here:

componentDidUpdate() {
  if (!this.state.isEnabled) {
    this.setState({ isEnabled: true })
  }
}

but this would still fail:

componentDidUpdate() {
  this.setState({ isEnabled: true })
}

An issue here would be that it's still not entirely guaranteed that more complex use cases wouldn't still end up in an infinite loop.

[ljharb]

The comment you linked to says it has to be inside a function - not inside a conditional check.

[himynameisdave]

This would be awesome. I think it's fine if it's in a conditional or if you move the setState call off to another method.

[brandonburkett]

In the react docs for componentDidUpdate, it says You may call setState() immediately in componentDidUpdate() but note that it must be wrapped in a condition and the example is an if statement.

[ljharb]

The condition would have to be one that prevents an infinite loop, which isn’t something that’s be statically knowable.

[himynameisdave]

@ljharb true, but I still want to use this rule. Maybe I'll just change it to a warning in our codebase, but overall I prefer rules to be strict so that they cannot be committed at all.

[gaurav5430]

any updates on whether this is going to be an option or not ?