diff --git a/x/logic/predicate/json_test.go b/x/logic/predicate/json_test.go
index c2af4dc4..dac1b61c 100644
--- a/x/logic/predicate/json_test.go
+++ b/x/logic/predicate/json_test.go
@@ -147,6 +147,14 @@ func TestJsonProlog(t *testing.T) {
 			},
 			// ** JSON -> Prolog **
 			// Array
+			{
+				description: "convert empty json array into prolog",
+				query:       `json_prolog('[]', Term).`,
+				wantResult: []types.TermResults{{
+					"Term": "@([])",
+				}},
+				wantSuccess: true,
+			},
 			{
 				description: "convert json array into prolog",
 				query:       `json_prolog('["foo", "bar"]', Term).`,
@@ -155,6 +163,14 @@ func TestJsonProlog(t *testing.T) {
 				}},
 				wantSuccess: true,
 			},
+			{
+				description: "convert json array with null element into prolog",
+				query:       `json_prolog('[null]', Term).`,
+				wantResult: []types.TermResults{{
+					"Term": "[@(null)]",
+				}},
+				wantSuccess: true,
+			},
 			{
 				description: "convert json string array into prolog",
 				query:       `json_prolog('["string with space", "bar"]', Term).`,
@@ -174,6 +190,22 @@ func TestJsonProlog(t *testing.T) {
 				}},
 				wantSuccess: true,
 			},
+			{
+				description: "convert atom term to json",
+				query:       `json_prolog(Json, foo).`,
+				wantResult: []types.TermResults{{
+					"Json": "'\"foo\"'",
+				}},
+				wantSuccess: true,
+			},
+			{
+				description: "convert string with space to json",
+				query:       `json_prolog(Json, 'foo bar').`,
+				wantResult: []types.TermResults{{
+					"Json": "'\"foo bar\"'",
+				}},
+				wantSuccess: true,
+			},
 			{
 				description: "convert string with space to json",
 				query:       `json_prolog(Json, 'foo bar').`,
@@ -182,6 +214,14 @@ func TestJsonProlog(t *testing.T) {
 				}},
 				wantSuccess: true,
 			},
+			{
+				description: "convert empty-list atom term to json",
+				query:       `json_prolog(Json, []).`,
+				wantResult: []types.TermResults{{
+					"Json": "'\"[]\"'",
+				}},
+				wantSuccess: true,
+			},
 			// ** Prolog -> JSON **
 			// Object
 			{
@@ -252,6 +292,14 @@ func TestJsonProlog(t *testing.T) {
 			},
 			// ** Prolog -> Json **
 			// Array
+			{
+				description: "convert empty json array from prolog",
+				query:       `json_prolog(Json, @([])).`,
+				wantResult: []types.TermResults{{
+					"Json": "[]",
+				}},
+				wantSuccess: true,
+			},
 			{
 				description: "convert json array from prolog",
 				query:       `json_prolog(Json, [foo,bar]).`,
@@ -260,6 +308,14 @@ func TestJsonProlog(t *testing.T) {
 				}},
 				wantSuccess: true,
 			},
+			{
+				description: "convert json array with null element from prolog",
+				query:       `json_prolog(Json, [@(null)]).`,
+				wantResult: []types.TermResults{{
+					"Json": "'[null]'",
+				}},
+				wantSuccess: true,
+			},
 			{
 				description: "convert json string array from prolog",
 				query:       `json_prolog(Json, ['string with space',bar]).`,
@@ -340,7 +396,6 @@ func TestJsonProlog(t *testing.T) {
 										So(sols.Err(), ShouldBeNil)
 
 										if tc.wantSuccess {
-											So(len(got), ShouldBeGreaterThan, 0)
 											So(len(got), ShouldEqual, len(tc.wantResult))
 											for iGot, resultGot := range got {
 												for varGot, termGot := range resultGot {
@@ -404,6 +459,11 @@ func TestJsonPrologWithMoreComplexStructBidirectional(t *testing.T) {
 				term:        "json([a-b])",
 				wantSuccess: false,
 			},
+			{
+				json:        `'{"key1":null,"key2":[],"key3":{"nestedKey1":null,"nestedKey2":[],"nestedKey3":["a",null,null]}}'`,
+				term:        `json([key1- @(null),key2- @([]),key3-json([nestedKey1- @(null),nestedKey2- @([]),nestedKey3-[a,@(null),@(null)]])])`,
+				wantSuccess: true,
+			},
 		}
 		for nc, tc := range cases {
 			Convey(fmt.Sprintf("#%d : given the json: %s and the term %s", nc, tc.json, tc.term), func() {