refactor: mv custom filter test

test/integration/builtin/filters/custom.ts

@@ -1,15 +0,0 @@
-import { test, liquid } from '../../../stub/render'
-
-describe('filters/custom', function () {
-  liquid.registerFilter('obj_test', function () {
-    return JSON.stringify(arguments)
-  })
-  it('should support object', () => test(
-    `{{ "a" | obj_test: k1: "v1", k2: foo }}`,
-    '{"0":"a","1":["k1","v1"],"2":["k2","bar"]}'
-  ))
-  it('should support mixed object', () => test(
-    `{{ "a" | obj_test: "something", k1: "v1", k2: foo }}`,
-    '{"0":"a","1":"something","2":["k1","v1"],"3":["k2","bar"]}'
-  ))
-})

test/integration/register-filters/custom.ts

@@ -0,0 +1,17 @@
+import { test, liquid } from '../../stub/render'
+
+describe('registerFilter', function () {
+  describe('object arguments', function () {
+    liquid.registerFilter('obj_test', function () {
+      return JSON.stringify(arguments)
+    })
+    it('should support object', () => test(
+      `{{ "a" | obj_test: k1: "v1", k2: foo }}`,
+      '{"0":"a","1":["k1","v1"],"2":["k2","bar"]}'
+    ))
+    it('should support mixed object', () => test(
+      `{{ "a" | obj_test: "something", k1: "v1", k2: foo }}`,
+      '{"0":"a","1":"something","2":["k1","v1"],"3":["k2","bar"]}'
+    ))
+  })
+})