✅ Add missing tests for code examples (#14569)

Co-authored-by: Sebastián Ramírez <tiangolo@gmail.com>
Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
Co-authored-by: Nils-Hero Lindemann <nilsherolindemann@proton.me>

tests/test_tutorial/test_metadata/test_tutorial002.py

@@ -0,0 +1,42 @@
+from fastapi.testclient import TestClient
+
+from docs_src.metadata.tutorial002_py39 import app
+
+client = TestClient(app)
+
+
+def test_items():
+    response = client.get("/items/")
+    assert response.status_code == 200, response.text
+    assert response.json() == [{"name": "Foo"}]
+
+
+def test_get_openapi_json_default_url():
+    response = client.get("/openapi.json")
+    assert response.status_code == 404, response.text
+
+
+def test_openapi_schema():
+    response = client.get("/api/v1/openapi.json")
+    assert response.status_code == 200, response.text
+    assert response.json() == {
+        "openapi": "3.1.0",
+        "info": {
+            "title": "FastAPI",
+            "version": "0.1.0",
+        },
+        "paths": {
+            "/items/": {
+                "get": {
+                    "summary": "Read Items",
+                    "operationId": "read_items_items__get",
+                    "responses": {
+                        "200": {
+                            "description": "Successful Response",
+                            "content": {"application/json": {"schema": {}}},
+                        }
+                    },
+                }
+            }
+        },
+    }

tests/test_tutorial/test_metadata/test_tutorial003.py

@@ -0,0 +1,53 @@
+from fastapi.testclient import TestClient
+
+from docs_src.metadata.tutorial003_py39 import app
+
+client = TestClient(app)
+
+
+def test_items():
+    response = client.get("/items/")
+    assert response.status_code == 200, response.text
+    assert response.json() == [{"name": "Foo"}]
+
+
+def test_openapi_schema():
+    response = client.get("/openapi.json")
+    assert response.status_code == 200, response.text
+    assert response.json() == {
+        "openapi": "3.1.0",
+        "info": {
+            "title": "FastAPI",
+            "version": "0.1.0",
+        },
+        "paths": {
+            "/items/": {
+                "get": {
+                    "summary": "Read Items",
+                    "operationId": "read_items_items__get",
+                    "responses": {
+                        "200": {
+                            "description": "Successful Response",
+                            "content": {"application/json": {"schema": {}}},
+                        }
+                    },
+                }
+            }
+        },
+    }
+
+
+def test_swagger_ui_default_url():
+    response = client.get("/docs")
+    assert response.status_code == 404, response.text
+
+
+def test_swagger_ui_custom_url():
+    response = client.get("/documentation")
+    assert response.status_code == 200, response.text
+    assert "<title>FastAPI - Swagger UI</title>" in response.text
+
+
+def test_redoc_ui_default_url():
+    response = client.get("/redoc")
+    assert response.status_code == 404, response.text