FIR: allow nullable types in diagnostic parameters

idea/idea-frontend-fir/idea-fir-low-level-api/src/org/jetbrains/kotlin/idea/fir/low/level/api/diagnostics/FirIdeDiagnosticReporter.kt

@@ -41,28 +41,28 @@ private fun FirLightDiagnostic.toPsiDiagnostic(): FirPsiDiagnostic<*> {
             psiSourceElement,
             a,
             severity,
-            factory as FirDiagnosticFactory1<PsiElement, Any>
+            factory as FirDiagnosticFactory1<PsiElement, Any?>
         )
 
         is FirLightDiagnosticWithParameters2<*, *> -> FirPsiDiagnosticWithParameters2(
             psiSourceElement,
             a, b,
             severity,
-            factory as FirDiagnosticFactory2<PsiElement, Any, Any>
+            factory as FirDiagnosticFactory2<PsiElement, Any?, Any?>
         )
 
         is FirLightDiagnosticWithParameters3<*, *, *> -> FirPsiDiagnosticWithParameters3(
             psiSourceElement,
             a, b, c,
             severity,
-            factory as FirDiagnosticFactory3<PsiElement, Any, Any, Any>
+            factory as FirDiagnosticFactory3<PsiElement, Any?, Any?, Any?>
         )
 
         is FirLightDiagnosticWithParameters4<*, *, *, *> -> FirPsiDiagnosticWithParameters4(
             psiSourceElement,
             a, b, c, d,
             severity,
-            factory as FirDiagnosticFactory4<PsiElement, Any, Any, Any, Any>
+            factory as FirDiagnosticFactory4<PsiElement, Any?, Any?, Any?, Any?>
         )
         else -> error("Unknown diagnostic type ${this::class.simpleName}")
     }

idea/idea-frontend-fir/idea-frontend-fir-generator/src/org/jetbrains/kotlin/idea/frontend/api/fir/generator/HLDiagnosticConverter.kt

@@ -73,16 +73,21 @@ object HLDiagnosticConverter {
 
 private object FirToKtConversionCreator {
     fun createConversion(type: KType): HLParameterConversion {
+        val nullable = type.isMarkedNullable
         val kClass = type.classifier as KClass<*>
         return tryMapAllowedType(kClass)
             ?: tryMapPsiElementType(type, kClass)
-            ?: tryMapFirTypeToKtType(kClass)
+            ?: tryMapFirTypeToKtType(kClass, nullable)
             ?: tryMapPlatformType(type, kClass)
             ?: error("Unsupported type $type, consider add corresponding mapping")
     }
 
-    private fun tryMapFirTypeToKtType(kClass: KClass<*>): HLParameterConversion? {
-        return typeMapping[kClass]
+    private fun tryMapFirTypeToKtType(kClass: KClass<*>, nullable: Boolean): HLParameterConversion? {
+        return if (nullable) {
+            nullableTypeMapping[kClass] ?: typeMapping[kClass]
+        } else {
+            typeMapping[kClass]
+        }
     }
 
     private fun tryMapAllowedType(kClass: KClass<*>): HLParameterConversion? {
@@ -116,6 +121,17 @@ private object FirToKtConversionCreator {
         return null
     }
 
+    private val nullableTypeMapping: Map<KClass<*>, HLFunctionCallConversion> = mapOf(
+        FirExpression::class to HLFunctionCallConversion(
+            "{0}?.source?.psi as? KtExpression",
+            KtExpression::class.createType(nullable = true),
+            importsToAdd = listOf(
+                "org.jetbrains.kotlin.psi.KtExpression",
+                "org.jetbrains.kotlin.fir.psi"
+            )
+        ),
+    )
+
     private val typeMapping: Map<KClass<*>, HLFunctionCallConversion> = mapOf(
         AbstractFirBasedSymbol::class to HLFunctionCallConversion(
             "firSymbolBuilder.buildSymbol({0}.fir as FirDeclaration)",

idea/idea-frontend-fir/idea-frontend-fir-generator/src/org/jetbrains/kotlin/idea/frontend/api/fir/generator/generatorUtils.kt

@@ -11,13 +11,14 @@ import kotlin.reflect.KType
 
 internal fun SmartPrinter.printTypeWithShortNames(type: KType) {
     fun typeConversion(type: KType): String {
+        val nullableSuffix = if (type.isMarkedNullable) "?" else ""
         val simpleName = (type.classifier as KClass<*>).simpleName!!
-        return if (type.arguments.isEmpty()) simpleName
+        return if (type.arguments.isEmpty()) simpleName + nullableSuffix
         else simpleName + type.arguments.joinToString(separator = ", ", prefix = "<", postfix = ">") {
             when (val typeArgument = it.type) {
                 null -> "*"
                 else -> typeConversion(typeArgument)
-            }
+            } + nullableSuffix
         }
     }
     print(typeConversion(type))

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/frontend/api/fir/diagnostics/KtDiagnosticConverter.kt

@@ -15,19 +15,19 @@ internal fun interface KtFirDiagnostic0Creator : KtFirDiagnosticCreator {
     fun KtFirAnalysisSession.create(diagnostic: FirSimpleDiagnostic<*>): KtFirDiagnostic<*>
 }
 
-internal fun interface KtFirDiagnostic1Creator<A : Any> : KtFirDiagnosticCreator {
+internal fun interface KtFirDiagnostic1Creator<A> : KtFirDiagnosticCreator {
     fun KtFirAnalysisSession.create(diagnostic: FirDiagnosticWithParameters1<*, A>): KtFirDiagnostic<*>
 }
 
-internal fun interface KtFirDiagnostic2Creator<A : Any, B : Any> : KtFirDiagnosticCreator {
+internal fun interface KtFirDiagnostic2Creator<A, B> : KtFirDiagnosticCreator {
     fun KtFirAnalysisSession.create(diagnostic: FirDiagnosticWithParameters2<*, A, B>): KtFirDiagnostic<*>
 }
 
-internal fun interface KtFirDiagnostic3Creator<A : Any, B : Any, C : Any> : KtFirDiagnosticCreator {
+internal fun interface KtFirDiagnostic3Creator<A, B, C> : KtFirDiagnosticCreator {
     fun KtFirAnalysisSession.create(diagnostic: FirDiagnosticWithParameters3<*, A, B, C>): KtFirDiagnostic<*>
 }
 
-internal fun interface KtFirDiagnostic4Creator<A : Any, B : Any, C : Any, D : Any> : KtFirDiagnosticCreator {
+internal fun interface KtFirDiagnostic4Creator<A, B, C, D> : KtFirDiagnosticCreator {
     fun KtFirAnalysisSession.create(diagnostic: FirDiagnosticWithParameters4<*, A, B, C, D>): KtFirDiagnostic<*>
 }
 
@@ -42,17 +42,17 @@ internal class KtDiagnosticConverter(private val conversions: Map<AbstractFirDia
                 is KtFirDiagnostic0Creator -> with(creator) {
                     create(diagnostic as FirSimpleDiagnostic<*>)
                 }
-                is KtFirDiagnostic1Creator<*> -> with(creator as KtFirDiagnostic1Creator<Any>) {
-                    create(diagnostic as FirDiagnosticWithParameters1<FirSourceElement, Any>)
+                is KtFirDiagnostic1Creator<*> -> with(creator as KtFirDiagnostic1Creator<Any?>) {
+                    create(diagnostic as FirDiagnosticWithParameters1<FirSourceElement, Any?>)
                 }
-                is KtFirDiagnostic2Creator<*, *> -> with(creator as KtFirDiagnostic2Creator<Any, Any>) {
-                    create(diagnostic as FirDiagnosticWithParameters2<FirSourceElement, Any, Any>)
+                is KtFirDiagnostic2Creator<*, *> -> with(creator as KtFirDiagnostic2Creator<Any?, Any?>) {
+                    create(diagnostic as FirDiagnosticWithParameters2<FirSourceElement, Any?, Any?>)
                 }
-                is KtFirDiagnostic3Creator<*, *, *> -> with(creator as KtFirDiagnostic3Creator<Any, Any, Any>) {
-                    create(diagnostic as FirDiagnosticWithParameters3<FirSourceElement, Any, Any, Any>)
+                is KtFirDiagnostic3Creator<*, *, *> -> with(creator as KtFirDiagnostic3Creator<Any?, Any?, Any?>) {
+                    create(diagnostic as FirDiagnosticWithParameters3<FirSourceElement, Any?, Any?, Any?>)
                 }
-                is KtFirDiagnostic4Creator<*, *, *, *> -> with(creator as KtFirDiagnostic4Creator<Any, Any, Any, Any>) {
-                    create(diagnostic as FirDiagnosticWithParameters4<FirSourceElement, Any, Any, Any, Any>)
+                is KtFirDiagnostic4Creator<*, *, *, *> -> with(creator as KtFirDiagnostic4Creator<Any?, Any?, Any?, Any?>) {
+                    create(diagnostic as FirDiagnosticWithParameters4<FirSourceElement, Any?, Any?, Any?, Any?>)
                 }
                 else -> error("Invalid KtFirDiagnosticCreator ${creator::class.simpleName}")
             }
@@ -67,19 +67,19 @@ internal class KtDiagnosticConverterBuilder private constructor() {
         conversions[diagnostic] = creator
     }
 
-    fun <A : Any> add(diagnostic: FirDiagnosticFactory1<*, A>, creator: KtFirDiagnostic1Creator<A>) {
+    fun <A> add(diagnostic: FirDiagnosticFactory1<*, A>, creator: KtFirDiagnostic1Creator<A>) {
         conversions[diagnostic] = creator
     }
 
-    fun <A : Any, B : Any> add(diagnostic: FirDiagnosticFactory2<*, A, B>, creator: KtFirDiagnostic2Creator<A, B>) {
+    fun <A, B> add(diagnostic: FirDiagnosticFactory2<*, A, B>, creator: KtFirDiagnostic2Creator<A, B>) {
         conversions[diagnostic] = creator
     }
 
-    fun <A : Any, B : Any, C : Any> add(diagnostic: FirDiagnosticFactory3<*, A, B, C>, creator: KtFirDiagnostic3Creator<A, B, C>) {
+    fun <A, B, C> add(diagnostic: FirDiagnosticFactory3<*, A, B, C>, creator: KtFirDiagnostic3Creator<A, B, C>) {
         conversions[diagnostic] = creator
     }
 
-    fun <A : Any, B : Any, C : Any, D : Any> add(diagnostic: FirDiagnosticFactory4<*, A, B, C, D>, creator: KtFirDiagnostic4Creator<A, B, C, D>) {
+    fun <A, B, C, D> add(diagnostic: FirDiagnosticFactory4<*, A, B, C, D>, creator: KtFirDiagnostic4Creator<A, B, C, D>) {
         conversions[diagnostic] = creator
     }