FIR: introduce synthetic property symbol hierarchy

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/synthetic/FirSyntheticProperty.kt

@@ -11,8 +11,7 @@ import org.jetbrains.kotlin.fir.declarations.*
 import org.jetbrains.kotlin.fir.expressions.FirAnnotation
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.references.FirControlFlowGraphReference
-import org.jetbrains.kotlin.fir.symbols.impl.FirAccessorSymbol
-import org.jetbrains.kotlin.fir.symbols.impl.FirBackingFieldSymbol
+import org.jetbrains.kotlin.fir.symbols.impl.FirSyntheticPropertySymbol
 import org.jetbrains.kotlin.fir.symbols.impl.FirDelegateFieldSymbol
 import org.jetbrains.kotlin.fir.types.ConeKotlinType
 import org.jetbrains.kotlin.fir.types.FirTypeRef
@@ -25,7 +24,7 @@ class FirSyntheticProperty(
     override val moduleData: FirModuleData,
     override val name: Name,
     override val isVar: Boolean,
-    override val symbol: FirAccessorSymbol,
+    override val symbol: FirSyntheticPropertySymbol,
     override val status: FirDeclarationStatus,
     override var resolvePhase: FirResolvePhase,
     override val getter: FirSyntheticPropertyAccessor,

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/synthetic/FirSyntheticPropertyBuilder.kt

@@ -9,13 +9,13 @@ import org.jetbrains.kotlin.fir.FirModuleData
 import org.jetbrains.kotlin.fir.declarations.DeprecationsPerUseSite
 import org.jetbrains.kotlin.fir.declarations.FirDeclarationStatus
 import org.jetbrains.kotlin.fir.declarations.FirSimpleFunction
-import org.jetbrains.kotlin.fir.symbols.impl.FirAccessorSymbol
+import org.jetbrains.kotlin.fir.symbols.impl.FirSyntheticPropertySymbol
 import org.jetbrains.kotlin.name.Name
 
 class FirSyntheticPropertyBuilder {
     lateinit var moduleData: FirModuleData
     lateinit var name: Name
-    lateinit var symbol: FirAccessorSymbol
+    lateinit var symbol: FirSyntheticPropertySymbol
     lateinit var delegateGetter: FirSimpleFunction
     lateinit var deprecation: DeprecationsPerUseSite
 

compiler/fir/tree/src/org/jetbrains/kotlin/fir/symbols/impl/FirFunctionSymbol.kt

@@ -80,10 +80,19 @@ class FirConstructorSymbol(
         get() = fir.delegatedConstructor?.isSuper ?: false
 }
 
-open class FirAccessorSymbol(
+/**
+ * This is a property symbol which is always bound to FirSyntheticProperty.
+ *
+ * Synthetic property symbol is effectively a combination of
+ * a property (which never exists in sources) and
+ * a getter which exists in sources and is either from Java or overrides another getter from Java.
+ */
+abstract class FirSyntheticPropertySymbol(
     propertyId: CallableId,
     val getterId: CallableId
-) : FirPropertySymbol(propertyId)
+) : FirPropertySymbol(propertyId) {
+    abstract fun copy(): FirSyntheticPropertySymbol
+}
 
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