Don't exclude properties for sealed classes either

Author: DonnieWest

server/src/main/kotlin/org/javacs/kt/completion/Completions.kt

@@ -365,7 +365,7 @@ private fun completeMembers(file: CompiledFile, cursor: Int, receiverExpr: KtExp
             val extensions = extensionFunctions(lexicalScope).filter { isExtensionFor(receiverType, it) }
             descriptors = members + extensions
 
-            if (!isCompanionOfEnum(receiverType)) {
+            if (!isCompanionOfEnum(receiverType) && !isCompanionOfSealed(receiverType)) {
                 return descriptors
             }
         }
@@ -393,6 +393,16 @@ private fun isCompanionOfEnum(kotlinType: KotlinType): Boolean {
     return DescriptorUtils.isEnumClass(classDescriptor?.containingDeclaration)
 }
 
+private fun isCompanionOfSealed(kotlinType: KotlinType): Boolean {
+    val classDescriptor = TypeUtils.getClassDescriptor(kotlinType)
+    val isCompanion = DescriptorUtils.isCompanionObject(classDescriptor)
+    if (!isCompanion) {
+        return false
+    }
+
+    return DescriptorUtils.isSealedClass(classDescriptor?.containingDeclaration)
+}
+
 private fun findPartialIdentifier(file: CompiledFile, cursor: Int): String {
     val line = file.lineBefore(cursor)
     if (line.matches(Regex(".*\\."))) return ""