Increase number of consecutive runs of ktlint in case format introduces new problem

[paul-dingemans]

Given code below:

class EnhanceStackTraceWithTreadDumpAsJsonTest : DebugTestBase() {
    @Test
    fun testEnhancedStackTraceFormatWithDeferred() = runTest {
        val enhancedStackTraceFromJson = Gson().fromJson(enhancedStackTraceAsJsonString, Array<StackTraceElementInfoFromJson>::class.java)
    }
}

and .editorconfig:

root = true

[**/*.{kt,kts}]
ktlint_code_style = ktlint_official
ktlint_experimental = enabled
ktlint_standard = enabled

then ktlint 0.50.0 is not able to format this in 3 consecutive runs.

After the first iteration, the code is transformed to:

class EnhanceStackTraceWithTreadDumpAsJsonTest : DebugTestBase() {
    @Test
    fun testEnhancedStackTraceFormatWithDeferred() =
        runTest {
            val enhancedStackTraceFromJson = Gson().fromJson(enhancedStackTraceAsJsonString, Array<StackTraceElementInfoFromJson>::class.java)
        }
}

But now line 5 is exceeding the max-line-length (defaulted to 140). After fixing this in the second iteration, the code is transformed to:

class EnhanceStackTraceWithTreadDumpAsJsonTest : DebugTestBase() {
    @Test
    fun testEnhancedStackTraceFormatWithDeferred() =
        runTest {
            val enhancedStackTraceFromJson = Gson().fromJson(
                enhancedStackTraceAsJsonString,
                Array<StackTraceElementInfoFromJson>::class.java
            )
        }
}

Next problem is that the multiline expression, starting at line 5, is wrapped in the third iteration. The code is transformed to:

class EnhanceStackTraceWithTreadDumpAsJsonTest : DebugTestBase() {
    @Test
    fun testEnhancedStackTraceFormatWithDeferred() =
        runTest {
            val enhancedStackTraceFromJson =
                Gson().fromJson(
                    enhancedStackTraceAsJsonString,
                    Array<StackTraceElementInfoFromJson>::class.java
                )
        }
}

And finally the last problem (a missing trailing comma at line 8 is identified) which is fixed in the fourth iteration:

class EnhanceStackTraceWithTreadDumpAsJsonTest : DebugTestBase() {
    @Test
    fun testEnhancedStackTraceFormatWithDeferred() =
        runTest {
            val enhancedStackTraceFromJson =
                Gson().fromJson(
                    enhancedStackTraceAsJsonString,
                    Array<StackTraceElementInfoFromJson>::class.java,
                )
        }
}

Because of the order in which the rules are executed, it is sometimes needed to iterate multiple times. Setting this number too high has consequences for total througput time in case an accidental endless loop is triggered (for example see #2128).

Options:

• Increase maximum number of consecutive runs to 5
• make the maximum number of consecutive runs configurable with current default of 3
• accept that occasionally multiple manual incovations are needed to fix all problems