fix: preserve GitHub label objects in create-issue response

The response schema declared labels as an array of strings while the GitHub
REST API returns them as objects. fast-json-stringify coerces each object to
the string "[object Object]" rather than failing, so the endpoint answers 200
with corrupted label data.

Restores the anyOf(string, object) shape the schema had before #23, and adds a
serialization test that drives the route through fastify.inject. The existing
unit tests call the controller with a plain mock reply, so they never run the
serializer and cannot observe this.

Author: jonsuguiyama

src/schemas/issues.schema.js

@@ -7,7 +7,23 @@ export const githubIssueModel = S.object()
   .prop('number', S.integer())
   .prop('title', S.string())
   .prop('body', S.anyOf([S.null(), S.string()]))
-  .prop('labels', S.array().items(S.string()))
+  .prop(
+    'labels',
+    S.array().items(
+      S.anyOf([
+        S.string(),
+        S.object()
+          .prop('id', S.integer())
+          .prop('node_id', S.string())
+          .prop('url', S.string().format('uri'))
+          .prop('name', S.string())
+          .prop('description', S.anyOf([S.null(), S.string()]))
+          .prop('color', S.anyOf([S.null(), S.string()]))
+          .prop('default', S.boolean())
+          .additionalProperties(true),
+      ]),
+    ),
+  )
   .prop('state', S.string().enum(['open', 'closed']))
   .prop('created_at', S.string().format('date-time'))
   .prop('url', S.string().format('uri'))

tests/issues.serialization.test.js

@@ -0,0 +1,103 @@
+import { expect } from 'chai';
+import f from 'fastify';
+import ky from 'ky';
+import { afterEach, beforeEach, describe, it } from 'mocha';
+import sinon from 'sinon';
+
+import { issuesRoutes } from '../src/routes/issues.routes.js';
+import { loadModels } from '../src/schemas/loadModels.js';
+import { cleanup, setupGitHubEnv } from './test.utils.js';
+
+/**
+ * Labels exactly as the GitHub REST API returns them: an array of objects.
+ * See https://docs.github.com/en/rest/issues/issues#get-an-issue
+ */
+const GITHUB_LABELS = [
+  {
+    color: 'ededed',
+    default: false,
+    description: null,
+    id: 6450392658,
+    name: 'REPORTED-BY-USER',
+    node_id: 'LA_kwDOJMP9Ms8AAAABgHkuUg',
+    url: 'https://api.github.com/repos/hasadna/open-bus-map-search/labels/REPORTED-BY-USER',
+  },
+];
+
+const VALID_BODY = {
+  actualBehavior: 'Does not work',
+  contactEmail: 'john@example.com',
+  contactName: 'John Doe',
+  description: 'Test description long enough',
+  environment: 'Test environment',
+  expectedBehavior: 'Should work',
+  reproducibility: 'always',
+  title: 'Test Issue',
+  type: 'bug',
+};
+
+/**
+ * These tests drive the route through `fastify.inject`, so the response passes
+ * through Fastify's schema serializer. The unit tests in `issues.test.js` call the
+ * controller with a plain mock `reply`, which never serializes and therefore cannot
+ * observe what the client actually receives.
+ */
+describe('createIssue response serialization', () => {
+  let app;
+  let post;
+
+  beforeEach(async () => {
+    setupGitHubEnv();
+    post = sinon.stub(ky, 'post');
+
+    app = f();
+    loadModels(app);
+    app.register(issuesRoutes, { prefix: 'issues' });
+    await app.ready();
+  });
+
+  afterEach(async () => {
+    cleanup();
+    await app.close();
+  });
+
+  it('should preserve GitHub label objects in the serialized response', async () => {
+    const githubIssue = {
+      created_at: new Date().toISOString(),
+      html_url: 'https://github.com/test/repo/issues/123',
+      id: 123,
+      labels: GITHUB_LABELS,
+      number: 123,
+      state: 'open',
+      title: 'Test Issue',
+      url: 'https://api.github.com/repos/test/repo/issues/123',
+    };
+
+    post.resolves({ json: () => Promise.resolve(githubIssue) });
+
+    const response = await app.inject({ method: 'POST', payload: VALID_BODY, url: '/issues/create' });
+
+    expect(response.statusCode).to.equal(200);
+    expect(response.json().data.labels).to.deep.equal(GITHUB_LABELS);
+  });
+
+  it('should still accept labels sent as plain strings', async () => {
+    const githubIssue = {
+      created_at: new Date().toISOString(),
+      html_url: 'https://github.com/test/repo/issues/124',
+      id: 124,
+      labels: ['REPORTED-BY-USER'],
+      number: 124,
+      state: 'open',
+      title: 'Test Issue',
+      url: 'https://api.github.com/repos/test/repo/issues/124',
+    };
+
+    post.resolves({ json: () => Promise.resolve(githubIssue) });
+
+    const response = await app.inject({ method: 'POST', payload: VALID_BODY, url: '/issues/create' });
+
+    expect(response.statusCode).to.equal(200);
+    expect(response.json().data.labels).to.deep.equal(['REPORTED-BY-USER']);
+  });
+});