Testcase for JX/JC array gaps

tests/ecmascript/test-bi-duktape-enc-jc.js

@@ -0,0 +1,18 @@
+/*
+ *  Duktape.enc() JC
+ */
+
+/*===
+[{"_undef":true},null,{"_undef":true},{"_undef":true},{"_undef":true},1,{"_undef":true}]
+===*/
+
+function test() {
+    // Array gaps: '{"_undef":true}'
+    print(Duktape.enc('jc', [ void 0, null,,,, 1,, ]));
+}
+
+try {
+    test();
+} catch (e) {
+    print(e.stack || e);
+}

tests/ecmascript/test-bi-duktape-enc-jx.js

@@ -0,0 +1,18 @@
+/*
+ *  Duktape.enc() JX
+ */
+
+/*===
+[undefined,null,undefined,undefined,undefined,1,undefined]
+===*/
+
+function test() {
+    // Array gaps: 'undefined'.
+    print(Duktape.enc('jx', [ void 0, null,,,, 1,, ]));
+}
+
+try {
+    test();
+} catch (e) {
+    print(e.stack || e);
+}