Fix query parse when return data undefined

src/core/smartContractQuery.ts

@@ -49,7 +49,7 @@ export class SmartContractQueryResponse {
         let returnMessage = payload["returnMessage"] || payload["ReturnMessage"];
 
         return new SmartContractQueryResponse({
-            returnDataParts: returnData?.map((item) => Buffer.from(item || "", "base64")),
+            returnDataParts: returnData?.map((item) => Buffer.from(item || "", "base64")) ?? [],
             returnCode: returnCode,
             returnMessage: returnMessage,
             function: functionName,

src/networkProviders/apiNetworkProvider.dev.net.spec.ts

@@ -382,4 +382,14 @@ describe("ApiNetworkProvider Tests", function () {
         const result = await apiProvider.queryContract(query);
         assert.equal(result.returnDataParts.length, 1);
     });
+
+    it("should query contract when undefined returnData", async () => {
+        const query = new SmartContractQuery({
+            contract: Address.newFromBech32("erd1qqqqqqqqqqqqqpgqf738mcf8f08kuwhn8dvtka5veyad2fqwu00sqnjgln"),
+            function: "getAllProposers",
+            arguments: [],
+        });
+        const result = await apiProvider.queryContract(query);
+        assert.equal(result.returnDataParts.length, 0);
+    });
 });

src/networkProviders/proxyNetworkProvider.dev.net.spec.ts

@@ -388,4 +388,14 @@ describe("ProxyNetworkProvider Tests", function () {
         const result = await proxy.queryContract(query);
         assert.equal(result.returnDataParts.length, 1);
     });
+
+    it("should query contract when undefined returnData", async () => {
+        const query = new SmartContractQuery({
+            contract: Address.newFromBech32("erd1qqqqqqqqqqqqqpgqf738mcf8f08kuwhn8dvtka5veyad2fqwu00sqnjgln"),
+            function: "getAllProposers",
+            arguments: [],
+        });
+        const result = await proxy.queryContract(query);
+        assert.equal(result.returnDataParts.length, 0);
+    });
 });