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kotlinlang

Kotest *<https://kotest.io/docs/framework/framework.html#test-with-style|uses>* following format for defining specs (tests):
```class MyTests : StringSpec({
   "length should return size of string" {
      "hello".length shouldBe 5
   }
})```
Kotest (standard ruleset) formats it as following:
```class MyTests : StringSpec(
  {
    "length should return size of string" {
      "hello".length shouldBe 5
    }
  },
)```
How do I prevent it from add a newline for the spec body lambda here? I see there was already this <https://github.com/pinterest/ktlint/issues/810|ticket> for this from 4 years ago but curious if there's a solution here? What's the rule controlling this behavior?

I think it's multiline-expression-wrapping that causes the issue. You can disable it by adding this to your `.editorconfig`
```ktlint_standard_string-template-indent = disabled
ktlint_standard_multiline-expression-wrapping = disabled```

I think it's the trailing comma at the call site actually

`ij_kotlin_allow_trailing_comma_on_call_site = false` disabling this fixes it

Is there a way to make trailing commas at callsite optional? That is, they don't get added automatically but they don't get removed either.

It's nice to have in most cases, but I guess I wish it didn't remove the comms even if the rule is disabled

No this can not be configured.  Either you choose to use them always, or never. Ktlint is more restrictive in this then default formatter of Intellij IDEA.