Merge pull request #1410 from informalsystems/gabriela/serialize-sets

Fix serialization of Sets

Author: bugarela

CHANGELOG.md

@@ -32,6 +32,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Removed a dependency causing deprecation errors messages to be emitted.
   (#1380)
 - Fixed a type checker bug causing too general types to be inferred (#1409).
+- Fixes serialization of Sets in JSON outputs (#1410).
 
 ### Security
 

quint/src/cliCommands.ts

@@ -901,7 +901,7 @@ function addItfHeader(source: string, status: string, traceInJson: any): any {
 
 // Preprocess troublesome types so they are represented in JSON.
 //
-// We need it particularly because, by default, serialization of Map
+// We need it particularly because, by default, serialization of Map and Set
 // objects just produces an empty object
 // (see https://stackoverflow.com/questions/46634449/json-stringify-of-object-of-map-return-empty)
 //
@@ -910,6 +910,9 @@ function replacer(_key: String, value: any): any {
   if (value instanceof Map) {
     // Represent Maps as JSON objects
     return Object.fromEntries(value)
+  } else if (value instanceof Set) {
+    // Represent Sets as JSON arrays
+    return Array.from(value)
   } else {
     return value
   }