Fix jvmTarget default divergence between KGP & IDE after change to 1.8

build-common/src/org/jetbrains/kotlin/compilerRunner/ArgumentUtils.java

@@ -29,21 +29,43 @@ import org.jetbrains.kotlin.cli.common.arguments.Argument;
 import org.jetbrains.kotlin.cli.common.arguments.CommonToolArguments;
 import org.jetbrains.kotlin.cli.common.arguments.InternalArgument;
 import org.jetbrains.kotlin.cli.common.arguments.ParseCommandLineArgumentsKt;
+import org.jetbrains.kotlin.idea.ExplicitDefaultSubstitutor;
+import org.jetbrains.kotlin.idea.ExplicitDefaultSubstitutorsKt;
 import org.jetbrains.kotlin.utils.StringsKt;
 
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Type;
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.List;
-import java.util.Objects;
+import java.util.*;
 
 public class ArgumentUtils {
-    private ArgumentUtils() {}
+    private ArgumentUtils() {
+    }
 
     @NotNull
     public static List<String> convertArgumentsToStringList(@NotNull CommonToolArguments arguments)
             throws InstantiationException, IllegalAccessException, InvocationTargetException {
+        List<String> convertedArguments = convertArgumentsToStringListInternal(arguments);
+
+        Map<KClass<? extends CommonToolArguments>, Collection<ExplicitDefaultSubstitutor>> defaultSubstitutorsMap =
+                ExplicitDefaultSubstitutorsKt.getDefaultSubstitutors();
+        KClass<? extends CommonToolArguments> argumentsKClass = JvmClassMappingKt.getKotlinClass(arguments.getClass());
+        Collection<ExplicitDefaultSubstitutor> defaultSubstitutors = defaultSubstitutorsMap.get(argumentsKClass);
+        if (defaultSubstitutors != null) {
+            for (ExplicitDefaultSubstitutor substitutor : defaultSubstitutors) {
+                if (substitutor.isSubstitutable(convertedArguments)) convertedArguments.addAll(substitutor.getNewSubstitution());
+            }
+        }
+        return convertedArguments;
+    }
+
+    @NotNull
+    public static List<String> convertArgumentsToStringListNoDefaults(@NotNull CommonToolArguments arguments)
+            throws InstantiationException, IllegalAccessException, InvocationTargetException {
+        return convertArgumentsToStringListInternal(arguments);
+    }
+
+    private static List<String> convertArgumentsToStringListInternal(@NotNull CommonToolArguments arguments)
+            throws InstantiationException, IllegalAccessException, InvocationTargetException {
         List<String> result = new ArrayList<>();
         Class<? extends CommonToolArguments> argumentsClass = arguments.getClass();
         convertArgumentsToStringList(arguments, argumentsClass.newInstance(), JvmClassMappingKt.getKotlinClass(argumentsClass), result);

build-common/src/org/jetbrains/kotlin/idea/explicitDefaultSubstitutors.kt

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2010-2021 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.idea
+
+import org.jetbrains.kotlin.cli.common.arguments.Argument
+import org.jetbrains.kotlin.cli.common.arguments.CommonToolArguments
+import org.jetbrains.kotlin.cli.common.arguments.K2JVMCompilerArguments
+import org.jetbrains.kotlin.config.JvmTarget
+import kotlin.reflect.KClass
+import kotlin.reflect.KProperty1
+import kotlin.reflect.full.findAnnotation
+
+val defaultSubstitutors: Map<KClass<out CommonToolArguments>, Collection<ExplicitDefaultSubstitutor>> =
+    mapOf(K2JVMCompilerArguments::class to listOf(JvmTargetDefaultSubstitutor))
+
+sealed class ExplicitDefaultSubstitutor {
+    abstract val substitutedProperty: KProperty1<out CommonToolArguments, String?>
+    abstract val oldSubstitution: List<String>
+    abstract val newSubstitution: List<String>
+    abstract fun isSubstitutable(args: List<String>): Boolean
+
+    protected val argument: Argument by lazy {
+        substitutedProperty.findAnnotation() ?: error("Property \"${substitutedProperty.name}\" has no Argument annotation")
+    }
+}
+
+object JvmTargetDefaultSubstitutor : ExplicitDefaultSubstitutor() {
+    override val substitutedProperty
+        get() = K2JVMCompilerArguments::jvmTarget
+    private val oldDefault: String
+        get() = JvmTarget.JVM_1_6.description
+    private val newDefault: String
+        get() = JvmTarget.JVM_1_8.description
+
+    private fun prepareSubstitution(default: String): List<String> = listOf(argument.value, default)
+
+    override val oldSubstitution: List<String>
+        get() = prepareSubstitution(oldDefault)
+    override val newSubstitution: List<String>
+        get() = prepareSubstitution(newDefault)
+
+    override fun isSubstitutable(args: List<String>): Boolean = argument.value !in args
+}