How to write TC against a certain Kotlin version

[atulgpt]

For this I tried to write TC like below

@Test
fun `does not report when language settings is below than DeprecatedSinceKotlin version`() {
    val code = """
//                @Deprecated("deprecation message")
//                @DeprecatedSinceKotlin(warningSince = "1.4")
        fun foo() {
            "".toLowerCase()
        }
        
        fun test() {
            foo()
        }
    """.trimIndent()
    assertThat(
        subject.lintWithContext(
            env,
            code,
            languageVersionSettings = FakeLanguageVersionSettings(LanguageVersion.KOTLIN_1_3),
        )
    ).isEmpty()
}

here toLowerCase() is annotated with @DeprecatedSinceKotlin(warningSince = "1.5", errorSince = "2.1") so it should not give any compilation error but when I run the TC I get the error e: file:///Users/username/detekt/detekt-rules-errorprone/src/test/kotlin/dev/detekt/rules/bugs/DeprecationSpec.kt:193:8 'fun String.toLowerCase(): String' is deprecated. Use lowercase() instead.

I have updated the lintWithContext like below to pass the languageVersionSettings to complier configuration but it still gives the above error

fun <T> T.lintWithContext(
    environment: KotlinEnvironmentContainer,
    @Language("kotlin") content: String,
    @Language("kotlin") vararg dependencyContents: String,
    languageVersionSettings: LanguageVersionSettings = environment.configuration.languageVersionSettings,
    allowCompilationErrors: Boolean = false,
): List<Finding> where T : Rule, T : RequiresAnalysisApi {
    val newComplierConfig = if (languageVersionSettings != environment.configuration.languageVersionSettings) {
        CompilerConfiguration().apply {
            put(CommonConfigurationKeys.LANGUAGE_VERSION_SETTINGS, languageVersionSettings)
        }
    } else {
        environment.configuration
    }
    val ktFile = KotlinAnalysisApiEngine.compile(
        code = content,
        dependencyCodes = dependencyContents.toList(),
        javaSourceRoots = newComplierConfig.javaSourceRoots.map(::Path),
        allowCompilationErrors = allowCompilationErrors,
        configuration = newComplierConfig
    )
    return visitFile(ktFile, languageVersionSettings).filterSuppressed(this)
        .sortedWith(findingComparator)
}

I am not if there is some other way to achieve this

context: It used to pass earlier with the code mentioned in the #4084 (comment) but now it doesn't. Not sure is there is some other way(or already a tracking issue) if not then I can create an issue

[BraisGabin]

That's similar to what Toshiaki did here: https://github.com/detekt/detekt/pull/8436/files#diff-2fefb6430b5a3c1a148a97da349e0481f60d3ff6c72535f44fd9ca360b3a8830

If you need that you can take his diff. That PR is a bit stuck.

[atulgpt]

In my case passing languageVersionSettings was still not working and when I passed the version LanguageVersion.KOTLIN_1_3, it still failed giving error for the deprecated function toLowerString which is warning after 1.5