kotlin:S1656 Should recognize setter method of the variable and Livedata

[jihun.im]

versions used

• SonarScanner 4.2.0.1873-macosx
• Sonarqube 8.2.0.32929 Docker

I am not sure if this is categorized as False-positive.

There could be additional operation other than just assigning value in the setter method.
In this case this is not an issue.

For e.g.

 private fun updateViewLayoutParameters() {
        rootView.layoutParams.height = myConfig.panelHeight
        // To call parent.onSetLayoutParams() and requestLayout()
        rootView.layoutParams = rootView.layoutParams

This code triggers View#setLayoutParams

Moreover, in Android usecase, there is Livedata.
If it is a LiveData, self-assigning calls Observer:onChanged(T).
In this case this is not an issue.

fun doSomething() {
    // ...
    myViewModel.name.observe(this, myObserver)
    myViewModel.name.value = viewModel.name.value
}

[Lena (Elena Vilchik)]

Hi,

Thanks for reporting this false positive (you’ve chosen a good category!). Still I’m afraid we will not fix it any time soon. The only way to ignore such cases is to have the information about setter/getter of the expression on lhs/rhs. We don’t have that info during analysis and I don’t think we will have it any time soon. Also even if this code is not a bug, it’s pretty confusing for the maintainers, so I hope it is not a frequent pattern in your code, so resolving such issues as “false positive” or “won’t fix” is acceptable.

Sorry for the inconvenience and thanks for the feedback anyway!