fix group_by and add test

Author: Francesca-Bit

lib/query/woqlQuery.js

@@ -1538,9 +1538,9 @@ WOQLQuery.prototype.group_by = function (gvarlist, groupedvar, output, groupquer
   this.cursor['@type'] = 'GroupBy';
   this.cursor.group_by = [];
 
-  if (typeof gvarlist === 'string') gvarlist = [gvarlist];
+  if (typeof gvarlist === 'string' || gvarlist instanceof Var) gvarlist = [gvarlist];
   this.cursor.group_by = this.rawVarList(gvarlist);
-  if (typeof groupedvar === 'string') groupedvar = [groupedvar];
+  if (typeof groupedvar === 'string' || groupedvar instanceof Var) groupedvar = [groupedvar];
   this.cursor.template = this.rawVarList(groupedvar);
   this.cursor.grouped = this.varj(output);
   return this.addSubQuery(groupquery);

test/woql.spec.js

@@ -313,6 +313,19 @@ describe('woql queries', () => {
     expect(woqlObject.json()).to.eql(woqlJson.memberJson);
   });
 
+  it('check the group_by with variables', () => {
+    let v = WOQL.Vars("person", "label", "eyes", "group");
+    const query = WOQL.group_by(
+      v.eyes,
+      v.label,
+      v.group,
+      WOQL.and(WOQL.triple(v.person, "rdf:type", "@schema:People"), 
+              WOQL.triple(v.person, "label", v.label),
+              WOQL.triple(v.person, "eye_color", v.eyes)))
+
+    expect(query.json()).to.eql(woqlJson.groupbyJsonWithVars);
+  })
+
   it('check the group_by method', () => {
     const woqlObject = WOQL.group_by(['v:A', 'v:B'], ['v:C'], 'v:New');
     const woqlObject01 = WOQL.group_by(['v:A', 'v:B'], ['v:C'], 'v:New').triple('v:A', 'v:B', 'v:C');

test/woqlJson/woqlJson.js

@@ -56,6 +56,69 @@ module.exports = {
       variable: 'list_obj',
     },
   },
+  groupbyJsonWithVars:{
+    "@type": "GroupBy",
+    "group_by": [
+      "eyes"
+    ],
+    "template": [
+      "label"
+    ],
+    "grouped": {
+      "@type": "Value",
+      "variable": "group"
+    },
+    "query": {
+      "@type": "And",
+      "and": [
+        {
+          "@type": "Triple",
+          "subject": {
+            "@type": "NodeValue",
+            "variable": "person"
+          },
+          "predicate": {
+            "@type": "NodeValue",
+            "node": "rdf:type"
+          },
+          "object": {
+            "@type": "Value",
+            "node": "@schema:People"
+          }
+        },
+        {
+          "@type": "Triple",
+          "subject": {
+            "@type": "NodeValue",
+            "variable": "person"
+          },
+          "predicate": {
+            "@type": "NodeValue",
+            "node": "label"
+          },
+          "object": {
+            "@type": "Value",
+            "variable": "label"
+          }
+        },
+        {
+          "@type": "Triple",
+          "subject": {
+            "@type": "NodeValue",
+            "variable": "person"
+          },
+          "predicate": {
+            "@type": "NodeValue",
+            "node": "eye_color"
+          },
+          "object": {
+            "@type": "Value",
+            "variable": "eyes"
+          }
+        }
+      ]
+    }
+  },
   groupbyJson: {
     '@type': 'GroupBy',
     group_by: ['A', 'B'],