Fix java.lang.ClassCastException is reading default yaml config

[picklebento]

Stacktrace

Caused by: java.lang.ClassCastException: java.lang.Integer cannot be cast to java.lang.String
	at io.gitlab.arturbosch.detekt.rules.style.MagicNumber$ignoreNumbers$2.invoke(MagicNumber.kt:259)
	at io.gitlab.arturbosch.detekt.rules.style.MagicNumber$ignoreNumbers$2.invoke(MagicNumber.kt:86)
	at io.gitlab.arturbosch.detekt.api.internal.TransformedConfigProperty.doGetValue(ConfigProperty.kt:87)
	at io.gitlab.arturbosch.detekt.api.internal.MemoizedConfigProperty.getValue(ConfigProperty.kt:64)
	at io.gitlab.arturbosch.detekt.api.internal.MemoizedConfigProperty.getValue(ConfigProperty.kt:60)
	at io.gitlab.arturbosch.detekt.rules.style.MagicNumber.getIgnoreNumbers(MagicNumber.kt:86)
	at io.gitlab.arturbosch.detekt.rules.style.MagicNumber.visitConstantExpression(MagicNumber.kt:138)

Root cause

With #3827, each line in a multi-line YAML array can be unquoted, such as

    ignoreNumbers:
      - -1
      - 0
      - 1
      - 2

This will lead to YAML config being parsed as List<Int>, but MagicNumber.ignoreValues() still have a default value of List<String>, causing the exception.

Fix

The pessimistic fix is to always print quotes in multi-line YAML array.

Testing

Since Gradle integration tests are only testing against latest published version, I have verified the fix through:

./gradlew :detekt-generator:generateDocumentation
./gradlew publishToMavenLocal
./gradlew :detekt-gradle-plugin:test
`

[marschwar]

An alternative approach would be to change the fun Config.valueOrDefaultCommaSeparated in PathFilters.kt to assume a List<Any> and call toString() on every item.

fun Config.valueOrDefaultCommaSeparated(
    key: String,
    default: List<String>
): List<String> {
    fun fallBack() = valueOrDefault(key, default.joinToString(","))
        .trim()
        .commaSeparatedPattern(",", ";")
        .toList()

    return try {
        valueOrDefault<List<Any>>(key, default).map { it.toString() }
    } catch (_: IllegalStateException) {
        fallBack()
    } catch (_: ClassCastException) {
        fallBack()
    }
}

[marschwar]

On second thought... Your solution is probably the safer bet for now. Since we only support lists that are parameterized with String it makes things easier to understand. Anything I can do to help?

[cortinico]

On second thought... Your solution is probably the safer bet for now.

I'd say let's go for that 👍

This PR is sort of crucial as it's currently blocking the release of 1.18.0.
We should also look into why those kind of bugs are happening whenever we're about to release a new version (and not before merging changes).

[marschwar]

The expectation in detekt-generator/src/test/resources/RuleSetConfig.yml has to be updated as well.

[marschwar]

I am so glad that you came across this before the release. Thank you

[codecov]

Codecov Report

Merging #3920 (a751d74) into main (3056e06) will decrease coverage by 0.14%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##               main    #3920      +/-   ##
============================================
- Coverage     83.59%   83.44%   -0.15%     
- Complexity     3123     3149      +26     
============================================
  Files           456      456              
  Lines          9015     9014       -1     
  Branches       1754     1754              
============================================
- Hits           7536     7522      -14     
- Misses          564      565       +1     
- Partials        915      927      +12     

Impacted Files	Coverage Δ
.../io/gitlab/arturbosch/detekt/generator/out/Yaml.kt	68.57% <ø> (-1.70%)	⬇️
...sch/detekt/rules/coroutines/SleepInsteadOfDelay.kt	72.00% <0.00%> (-8.00%)	⬇️
...arturbosch/detekt/generator/collection/KDocTags.kt	62.50% <0.00%> (-5.00%)	⬇️
...h/detekt/rules/style/DataClassContainsFunctions.kt	95.00% <0.00%> (-5.00%)	⬇️
...rturbosch/detekt/rules/bugs/UnnecessarySafeCall.kt	73.91% <0.00%> (-4.35%)	⬇️
...io/github/detekt/report/sarif/SarifOutputReport.kt	90.90% <0.00%> (-3.04%)	⬇️
...rturbosch/detekt/rules/style/UnusedPrivateClass.kt	70.66% <0.00%> (-2.67%)	⬇️
...ekt/generator/collection/DocumentationCollector.kt	85.00% <0.00%> (-2.50%)	⬇️
...ab/arturbosch/detekt/rules/style/UnnecessaryLet.kt	80.00% <0.00%> (-2.36%)	⬇️
...t/rules/style/UtilityClassWithPublicConstructor.kt	93.61% <0.00%> (-2.13%)	⬇️
... and 2 more

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