fix: do not assign undefined to x_filter keys

.gitignore

@@ -68,3 +68,5 @@ neo4j-version
 
 test/tck/*
 !test/tck/.gitkeep
+
+.history

src/translate.js

@@ -139,7 +139,10 @@ export const relationFieldOnNodeType = ({
   const filterParamKey = `${tailParams.paramIndex}_filter`;
   const fieldArgumentParams = subSelection[1];
   const filterParam = fieldArgumentParams[filterParamKey];
-  if (filterParam) {
+  if (
+    filterParam &&
+    typeof serializedFilterParam[filterParamKey] !== 'undefined'
+  ) {
     subSelection[1][filterParamKey] = serializedFilterParam[filterParamKey];
   }
 
@@ -264,7 +267,10 @@ export const relationTypeFieldOnNodeType = ({
   const filterParamKey = `${tailParams.paramIndex}_filter`;
   const fieldArgumentParams = subSelection[1];
   const filterParam = fieldArgumentParams[filterParamKey];
-  if (filterParam) {
+  if (
+    filterParam &&
+    typeof serializedFilterParam[filterParamKey] !== 'undefined'
+  ) {
     subSelection[1][filterParamKey] = serializedFilterParam[filterParamKey];
   }
 
@@ -426,7 +432,10 @@ const directedNodeTypeFieldOnRelationType = ({
       const filterParamKey = `${tailParams.paramIndex}_filter`;
       const fieldArgumentParams = subSelection[1];
       const filterParam = fieldArgumentParams[filterParamKey];
-      if (filterParam) {
+      if (
+        filterParam &&
+        typeof serializedFilterParam[filterParamKey] !== 'undefined'
+      ) {
         subSelection[1][filterParamKey] = serializedFilterParam[filterParamKey];
       }
       const whereClauses = [...temporalClauses, ...filterPredicates];

test/unit/cypherTest.test.js

@@ -4,6 +4,10 @@ import {
   augmentedSchemaCypherTestRunner
 } from '../helpers/cypherTestHelpers';
 
+import { augmentSchema, augmentTypeDefs, cypherQuery } from '../../src';
+import { makeExecutableSchema } from 'graphql-tools';
+import { graphql } from 'graphql';
+
 const CYPHER_PARAMS = {
   userId: 'user-id'
 };
@@ -4454,3 +4458,84 @@ test('Handle @cypher field with parameterized value for field of input type argu
     augmentedSchemaCypherTestRunner(t, graphQLQuery, {}, expectedCypherQuery)
   ]);
 });
+
+test('Cypher subquery filters with unfiltered parents', async t => {
+  const typeDefs = /* GraphQL */ `
+    type A_B_Relation @relation(name: "A_TO_B") {
+      from: A
+      to: B
+    }
+
+    type B_C_Relation @relation(name: "B_TO_C") {
+      from: B
+      to: C
+      active: Boolean!
+    }
+
+    type A {
+      bArray: [A_B_Relation!]!
+    }
+
+    type B {
+      cArray: [B_C_Relation!]!
+    }
+
+    type C {
+      id: ID!
+    }
+
+    type Query {
+      A: [A]
+    }
+  `;
+
+  const graphqlQuery = /* GraphQL */ `
+    {
+      A {
+        bArray {
+          B {
+            filteredCArray: cArray(filter: { active: true }) {
+              C {
+                id
+              }
+            }
+          }
+        }
+      }
+    }
+  `;
+
+  const expectedCypherQuery =
+    'MATCH (`a`:`A`) RETURN `a` {bArray: [(`a`)-[`a_bArray_relation`:`A_TO_B`]->(:`B`) | a_bArray_relation {B: head([(:`A`)-[`a_bArray_relation`]->(`a_bArray_B`:`B`) | a_bArray_B {cArray: [(`a_bArray_B`)-[`a_bArray_B_cArray_relation`:`B_TO_C`]->(:`C`) WHERE (`a_bArray_B_cArray_relation`.active = $1_filter.active) | a_bArray_B_cArray_relation {C: head([(:`B`)-[`a_bArray_B_cArray_relation`]->(`a_bArray_B_cArray_C`:`C`) | a_bArray_B_cArray_C { .id }]) }] }]) }] } AS `a`';
+  const expectedCypherParams = {
+    '1_filter': { active: true },
+    first: -1,
+    offset: 0
+  };
+
+  const resolvers = {
+    Query: {
+      A(object, params, ctx, resolveInfo) {
+        const [query, queryParams] = cypherQuery(params, ctx, resolveInfo);
+        t.is(query, expectedCypherQuery);
+        t.deepEqual(queryParams, expectedCypherParams);
+        return [];
+      }
+    }
+  };
+
+  const schema = augmentSchema(
+    makeExecutableSchema({
+      typeDefs: augmentTypeDefs(typeDefs),
+      resolvers
+    }),
+    { mutation: false }
+  );
+
+  // query the test schema with the test query, assertion is in the resolver
+  const resp = await graphql(schema, graphqlQuery);
+
+  t.deepEqual(resp.data.A, []);
+
+  return;
+});