Keep commas unescaped in query parameters

@here/olp-sdk-dataservice-api/lib/RequestBuilder.ts

@@ -68,7 +68,10 @@ export class UrlBuilder {
         } else if (typeof value === "boolean") {
             url += `${value}`;
         } else if (typeof value === "string") {
-            url += encodeURIComponent(value);
+            // The comma is a valid sub-delimiter of a query component and is
+            // used by the Data APIs as a list separator, the same way as for
+            // the array values below. Keep it unescaped.
+            url += encodeURIComponent(value).replace(/%2C/g, ",");
         } else if (Array.isArray(value)) {
             const encodedValues: string[] = [];
             value.forEach((val: string | number) => {
@@ -86,13 +89,17 @@ export class UrlBuilder {
      * @param url The base URL.
      * @param hasQuery Whether the base URL already contains query parameters.
      */
-    constructor(public url: string, public hasQuery: boolean = false) {}
+    constructor(
+        public url: string,
+        public hasQuery: boolean = false
+    ) {}
 
     /**
      * Appends a query parameter to the URL, either using '&key=value' or '?key=value'
      * depending on the [[hasQuery]] parameter.
      *
-     * Escapes all strings using `encodeURIComponent`.
+     * Escapes all strings using `encodeURIComponent`, except for the comma,
+     * which is kept unescaped as a list separator.
      *
      * String arrays are concatenated using commas.
      *

@here/olp-sdk-dataservice-api/test/RequestBuilder.test.ts

@@ -58,6 +58,17 @@ describe("UrlBuilderTest", function () {
         expect(testUrlBuilder.hasQuery).to.be.equal(true);
     });
 
+    it("Method appendQuery should appends parameters key, value with commas to the URL.", async function () {
+        const builderWithCommas = new UrlBuilder("test-url");
+        const mockedUrl = "test-url?testKey=testValue,testValue2";
+
+        builderWithCommas.appendQuery("testKey", "testValue,testValue2");
+
+        assert.isDefined(builderWithCommas);
+        expect(builderWithCommas.url).to.be.equal(mockedUrl);
+        expect(builderWithCommas.hasQuery).to.be.equal(true);
+    });
+
     it("Method appendQuery should not appends parameters to the URL if value is undefined.", async function () {
         const testUrlBuilder2 = new UrlBuilder("test-url");
         const mockedUrl = "test-url";