Bug on parameter's class that reached maximum line

[gbusiri]

Expected Behavior

No error.

Observed Behavior

Error.

Steps to Reproduce

I have parameter lambda code like this, let say my parameter is reached maximum limit of line :

There is error detected on open bracket (. I already clicked Format with ktlint, but still error.

Your Environment

• Version of ktlint used: 0.43.2
• Version of Gradle used (if applicable): AGP 7
• Operating System and version: MacOS Big Sur

[paul-dingemans]

Next time, please post your code instead of an image. It is more convenient when trying to reproduce a problem.

The code below is comparable to your example:

// Assume, the line breaks at the pipe symbol on the right                  -> |
val foo1: ((s1: String, s2: String, s3: String, s4: String, s5: String, s6: String) -> Unit)? = null

The ktlint --verbose --relative command results in:

src/main/kotlin/Issue1324.kt:1:1: Exceeded max line length (80) (cannot be auto-corrected) (max-line-length)
src/main/kotlin/Issue1324.kt:1:13: Parameter should be on a separate line (unless all parameters can fit a single line) (parameter-list-wrapping)
src/main/kotlin/Issue1324.kt:1:25: Parameter should be on a separate line (unless all parameters can fit a single line) (parameter-list-wrapping)
src/main/kotlin/Issue1324.kt:1:37: Parameter should be on a separate line (unless all parameters can fit a single line) (parameter-list-wrapping)
src/main/kotlin/Issue1324.kt:1:49: Parameter should be on a separate line (unless all parameters can fit a single line) (parameter-list-wrapping)
src/main/kotlin/Issue1324.kt:1:61: Parameter should be on a separate line (unless all parameters can fit a single line) (parameter-list-wrapping)
src/main/kotlin/Issue1324.kt:1:73: Parameter should be on a separate line (unless all parameters can fit a single line) (parameter-list-wrapping)
src/main/kotlin/Issue1324.kt:1:83: Missing newline before ")" (parameter-list-wrapping)

From this it can be seen that both the max-line-length and the parameter-list-wrapping report violations in the original code.

Auto-correct by the parameter-list-wrapping resolves the max line length violation and results in code below:

// Assume, next line exceeds the max line length                            -> |
val foo1: (
        (
            s1: String,
            s2: String,
            s3: String,
            s4: String,
            s5: String,
            s6: String
        ) -> Unit
    )? = null

but that same rule immediately reports now another lint error as you reported as well:

src/main/kotlin/Issue1324.kt:3:5: Unnecessary newline before "(" (parameter-list-wrapping)

So far, I have found no way to refactor the code manually in such a way that the code is accepted by both ktlint as well as by the IntelliJ default code formatting which nowadays is a requirement when we make (bugfixes on) rules. For example, the previous code sample will be transformed by IntelliJ default formatting to following:

// Assume, next line exceeds the max line length                            -> |
val foo1: (
    (
    s1: String,
    s2: String,
    s3: String,
    s4: String,
    s5: String,
    s6: String
) -> Unit
)? = null

This is horrible code.

For now, I see no other way for you to disable both rules and stick with one really long line:

val foo1: ((s1: String, s2: String, s3: String, s4: String, s5: String, s6: String) -> Unit)? = null // ktlint-disable max-line-length parameter-list-wrapping

Maybe, someone else has a briljant idea how to the resulting code should look like in such a way that both ktlint as well as IntelliJ default formatting do not alter that code. Next step would then be to fix the rules do that the code will be formatted as such.

[paul-dingemans]

For a function type wrapped in a nullable type it is perfectly acceptable to have a opening parenthesis starting on a new line. So the violation should indeed not have been reported. The conflicting formatting is caused by the indent rule. This will not be fixed (e.g. "uglified" to be compatible with IntelliJ IDEA formatting).