Added function to run tests by specified compiler version (#2148)

formats/json-tests/commonTest/src/kotlinx/serialization/SerializableOnPropertyTypeAndTypealiasTest.kt

@@ -3,6 +3,7 @@ package kotlinx.serialization
 import kotlinx.serialization.descriptors.*
 import kotlinx.serialization.encoding.*
 import kotlinx.serialization.json.*
+import kotlinx.serialization.test.runSince
 import kotlin.test.*
 
 @Serializable
@@ -82,8 +83,7 @@ class SerializableOnPropertyTypeAndTypealiasTest : JsonTestBase() {
     }
 
     @Test
-    @Ignore // TODO: Unignore in 1.8.20 (#1895)
-    fun testWithoutDefault() {
+    fun testWithoutDefault() = runSince("1.8.20") { // Ignored by #1895
         val t = TesterWithoutDefault(WithoutDefault("a"), WithoutDefault("b"), WithoutDefault("c"), WithoutDefault("d"))
         assertJsonFormAndRestored(
             TesterWithoutDefault.serializer(),

formats/json-tests/commonTest/src/kotlinx/serialization/test/CompilerVersions.kt

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2017-2023 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license.
+ */
+
+package kotlinx.serialization.test
+
+import kotlin.test.Test
+import kotlin.test.assertFalse
+import kotlin.test.assertTrue
+
+private val currentKotlinVersion = KotlinVersion.CURRENT
+
+private fun String.toKotlinVersion(): KotlinVersion {
+    val parts = split(".")
+    val intParts = parts.mapNotNull { it.toIntOrNull() }
+    if (parts.size != 3 || intParts.size != 3) error("Illegal kotlin version, expected format is 1.2.3")
+
+    return KotlinVersion(intParts[0], intParts[1], intParts[2])
+}
+
+internal fun runSince(kotlinVersion: String, test: () -> Unit) {
+    if (currentKotlinVersion >= kotlinVersion.toKotlinVersion()) {
+        test()
+    }
+}
+
+internal class CompilerVersionTest {
+    @Test
+    fun testSince() {
+        var executed = false
+
+        runSince("1.0.0") {
+            executed = true
+        }
+        assertTrue(executed)
+
+        executed = false
+        runSince("255.255.255") {
+            executed = true
+        }
+        assertFalse(executed)
+    }
+}