1 files changed, 163 insertions, 0 deletions
diff --git a/spec/frontend/lib/apollo/persistence_mapper_spec.js b/spec/frontend/lib/apollo/persistence_mapper_spec.js
new file mode 100644
index 00000000000..2efe28d2ca7
--- /dev/null
+++ b/spec/frontend/lib/apollo/persistence_mapper_spec.js
@@ -0,0 +1,163 @@
+import { persistenceMapper } from '~/lib/apollo/persistence_mapper';
+import NON_PERSISTED_CACHE from './mock_data/non_persisted_cache.json';
+import CACHE_WITH_PERSIST_DIRECTIVE from './mock_data/cache_with_persist_directive.json';
+import CACHE_WITH_PERSIST_DIRECTIVE_AND_FIELDS from './mock_data/cache_with_persist_directive_and_field.json';
+
+describe('lib/apollo/persistence_mapper', () => {
+  it('returns only empty root query if `@persist` directive or `__persist` field is not present', async () => {
+    const persistedData = await persistenceMapper(JSON.stringify(NON_PERSISTED_CACHE));
+
+    expect(JSON.parse(persistedData)).toEqual({ ROOT_QUERY: { __typename: 'Query' } });
+  });
+
+  it('returns root query with one `project` field if only `@persist` directive is present', async () => {
+    const persistedData = await persistenceMapper(JSON.stringify(CACHE_WITH_PERSIST_DIRECTIVE));
+
+    expect(JSON.parse(persistedData)).toEqual({
+      ROOT_QUERY: {
+        __typename: 'Query',
+        'project({"fullPath":"flightjs/Flight"}) @persist': {
+          __ref: 'Project:gid://gitlab/Project/6',
+        },
+      },
+      'Project:gid://gitlab/Project/6': { __typename: 'Project', id: 'gid://gitlab/Project/6' },
+    });
+  });
+
+  it('returns root query nested fields that contain `__persist` field if `@persist` directive is present', async () => {
+    const persistedData = await persistenceMapper(
+      JSON.stringify(CACHE_WITH_PERSIST_DIRECTIVE_AND_FIELDS),
+    );
+
+    expect(JSON.parse(persistedData)).toEqual({
+      ROOT_QUERY: {
+        __typename: 'Query',
+        'project({"fullPath":"flightjs/Flight"}) @persist': {
+          __ref: 'Project:gid://gitlab/Project/6',
+        },
+      },
+      'Project:gid://gitlab/Project/6': {
+        __typename: 'Project',
+        id: 'gid://gitlab/Project/6',
+        'issues({"after":null,"before":"eyJ1cGRhdGVkX2F0IjoiMjAyMy0wMS0wOSAwNDowNToyOS4yMzI5NDUwMDAgKzAwMDAiLCJpZCI6IjE1NjYifQ","includeSubepics":true,"last":20,"sort":"UPDATED_DESC","state":"opened","types":["ISSUE","INCIDENT","TEST_CASE","TASK"]})': {
+          __typename: 'IssueConnection',
+          __persist: true,
+          pageInfo: {
+            __typename: 'PageInfo',
+            hasNextPage: true,
+            hasPreviousPage: false,
+            startCursor:
+              'eyJ1cGRhdGVkX2F0IjoiMjAyMy0wMS0xMCAxMjozNjo1NC41NDYxNzEwMDAgKzAwMDAiLCJpZCI6IjQ4MyJ9',
+            endCursor:
+              'eyJ1cGRhdGVkX2F0IjoiMjAyMy0wMS0wOSAwNDowNToyOS4zMDE3NDcwMDAgKzAwMDAiLCJpZCI6IjE1NjcifQ',
+          },
+          nodes: [
+            {
+              __ref: 'Issue:gid://gitlab/Issue/483',
+            },
+            {
+              __ref: 'Issue:gid://gitlab/Issue/1585',
+            },
+            {
+              __ref: 'Issue:gid://gitlab/Issue/1584',
+            },
+            {
+              __ref: 'Issue:gid://gitlab/Issue/1583',
+            },
+            {
+              __ref: 'Issue:gid://gitlab/Issue/1582',
+            },
+            {
+              __ref: 'Issue:gid://gitlab/Issue/1581',
+            },
+            {
+              __ref: 'Issue:gid://gitlab/Issue/1580',
+            },
+            {
+              __ref: 'Issue:gid://gitlab/Issue/1579',
+            },
+            {
+              __ref: 'Issue:gid://gitlab/Issue/1578',
+            },
+            {
+              __ref: 'Issue:gid://gitlab/Issue/1577',
+            },
+            {
+              __ref: 'Issue:gid://gitlab/Issue/1576',
+            },
+            {
+              __ref: 'Issue:gid://gitlab/Issue/1575',
+            },
+            {
+              __ref: 'Issue:gid://gitlab/Issue/1574',
+            },
+            {
+              __ref: 'Issue:gid://gitlab/Issue/1573',
+            },
+            {
+              __ref: 'Issue:gid://gitlab/Issue/1572',
+            },
+            {
+              __ref: 'Issue:gid://gitlab/Issue/1571',
+            },
+            {
+              __ref: 'Issue:gid://gitlab/Issue/1570',
+            },
+            {
+              __ref: 'Issue:gid://gitlab/Issue/1569',
+            },
+            {
+              __ref: 'Issue:gid://gitlab/Issue/1568',
+            },
+            {
+              __ref: 'Issue:gid://gitlab/Issue/1567',
+            },
+          ],
+        },
+      },
+      'Issue:gid://gitlab/Issue/483': {
+        __typename: 'Issue',
+        __persist: true,
+        id: 'gid://gitlab/Issue/483',
+        iid: '31',
+        confidential: false,
+        createdAt: '2022-09-11T15:24:16Z',
+        downvotes: 1,
+        dueDate: null,
+        hidden: false,
+        humanTimeEstimate: null,
+        mergeRequestsCount: 1,
+        moved: false,
+        state: 'opened',
+        title: 'Instigate the Incident!',
+        updatedAt: '2023-01-10T12:36:54Z',
+        closedAt: null,
+        upvotes: 0,
+        userDiscussionsCount: 2,
+        webPath: '/flightjs/Flight/-/issues/31',
+        webUrl: 'https://gdk.test:3443/flightjs/Flight/-/issues/31',
+        type: 'INCIDENT',
+        assignees: {
+          __typename: 'UserCoreConnection',
+          nodes: [],
+        },
+        author: {
+          __ref: 'UserCore:gid://gitlab/User/1',
+        },
+        labels: {
+          __typename: 'LabelConnection',
+          nodes: [],
+        },
+        milestone: null,
+        taskCompletionStatus: {
+          __typename: 'TaskCompletionStatus',
+          completedCount: 0,
+          count: 0,
+        },
+        blockingCount: 0,
+        healthStatus: null,
+        weight: null,
+      },
+    });
+  });
+});