pinterest / ktlint

An anti-bikeshedding Kotlin linter with built-in formatter
https://pinterest.github.io/ktlint/
MIT License
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Conflict between `range-spacing` and `curly-spacing` #2539

Closed mgroth0 closed 4 months ago

mgroth0 commented 5 months ago

Expected Behavior

range-spacing and curly-spacing should work together.

Observed Behavior

It is possible to write code which makes it impossible to satisfy both rules.

Steps to Reproduce

Try to lint or format the following code.

val list = listOf(true)
println(list.count { it }..1)

If the } is directly before the ., curly-spacing will fail. If a space is added in between them, range-spacing will fail.

Your Environment

paul-dingemans commented 5 months ago

It is possible to write code which makes it impossible to satisfy both rules.

Yes, it is a bug when rules are conflicting.

But you can also see it as a sign that the code is not clear. The combination of a method chain with range operator is not very readable. I don't like any of the alternatives below.

println(list.count { it }..1)

Due to space before '{ it }there is a disconnect between the method chainlist.count { it }` and the range operator.

println(list.count { it } ..1)

This does not seem to be consistent. Why is space used before the range operator and not after it.

println(list.count { it } .. 1)

This looks consistent for this particular line. But it will not be consistent with other lines in which the range operator is used with integer constants in left and right hand side of operator.

In case that a variable is used like in code below, ktlint will not report any violations. So, the best approach to resolve th conflict seems to be that the curly-spacing rule should ignore the space after the } when followed by a range operator.

val bar = 0
println(bar..1)

For now, you can just suppress this specific example.

mgroth0 commented 5 months ago

But you can also see it as a sign that the code is not clear. The combination of a method chain with range operator is not very readable

I completely agree. I'd even favor a rule that disallows braces or other complex expressions from being part of a range.