FIR tree generator: merge fields from parents properly

compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/NodeConfigurator.kt

@@ -204,13 +204,8 @@ object NodeConfigurator : AbstractFieldConfigurator<FirTreeBuilder>(FirTreeBuild
             +field("value", "T", null)
         }
 
-        qualifiedAccessExpression.configure {
-            +field("source", sourceElementType, nullable = true, withReplace = true)
-        }
-
         functionCall.configure {
             +field("calleeReference", namedReference)
-            +field("source", sourceElementType, nullable = true, withReplace = true)
         }
 
         comparisonExpression.configure {
@@ -457,7 +452,6 @@ object NodeConfigurator : AbstractFieldConfigurator<FirTreeBuilder>(FirTreeBuild
             +field("originalExpression", qualifiedAccessExpression)
             +field("typesFromSmartCast", "Collection<ConeKotlinType>", null, customType = coneKotlinTypeType)
             +field("originalType", typeRef)
-            +field("source", sourceElementType, nullable = true, withReplace = true)
         }
 
         safeCallExpression.configure {
@@ -475,7 +469,6 @@ object NodeConfigurator : AbstractFieldConfigurator<FirTreeBuilder>(FirTreeBuild
         callableReferenceAccess.configure {
             +field("calleeReference", namedReference, withReplace = true).withTransform()
             +booleanField("hasQuestionMarkAtLHS", withReplace = true)
-            +field("source", sourceElementType, nullable = true, withReplace = true)
         }
 
         getClassCall.configure {
@@ -591,7 +584,6 @@ object NodeConfigurator : AbstractFieldConfigurator<FirTreeBuilder>(FirTreeBuild
 
         thisReceiverExpression.configure {
             +field("calleeReference", thisReference)
-            +field("source", sourceElementType, nullable = true, withReplace = true)
         }
 
         whenExpression.configure {

compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/model/Element.kt

@@ -104,7 +104,7 @@ class Element(val name: String, kind: Kind) : AbstractElement {
     }
 
     val parentFields: List<Field> by lazy {
-        val result = LinkedHashSet<Field>()
+        val result = LinkedHashMap<String, Field>()
         parents.forEach { parent ->
             val fields = parent.allFields.map { field ->
                 val copy = (field as? SimpleField)?.let { simpleField ->
@@ -119,9 +119,23 @@ class Element(val name: String, kind: Kind) : AbstractElement {
                     fromParent = true
                 }
             }
-            result.addAll(fields)
+            fields.forEach {
+                result.merge(it.name, it) { previousField, thisField ->
+                    val resultField = previousField.copy()
+                    if (thisField.withReplace) {
+                        resultField.withReplace = true
+                    }
+                    if (thisField.useNullableForReplace) {
+                        resultField.useNullableForReplace = true
+                    }
+                    if (thisField.isMutable) {
+                        resultField.isMutable = true
+                    }
+                    resultField
+                }
+            }
         }
-        result.toList()
+        result.values.toList()
     }
 
     override val allFirFields: List<Field> by lazy {