test: Cover bundled app templates with a smoke test

shiny/templates/markdown-stream/llm-enterprise/aws-bedrock-anthropic/app.py

@@ -8,7 +8,7 @@
 from chatlas import ChatBedrockAnthropic
 
 from shiny import reactive
-from shiny.express import ui
+from shiny.express import input, ui
 
 # Either explicitly set the AWS environment variables before launching the app, or set
 # them in a file named `.env`. The `python-dotenv` package will load `.env` as

shiny/templates/markdown-stream/llm-enterprise/azure-openai/app.py

@@ -5,7 +5,7 @@
 from chatlas import ChatAzureOpenAI
 
 from shiny import reactive
-from shiny.express import ui
+from shiny.express import input, ui
 
 # ChatAzureOpenAI() requires an API key from Azure OpenAI.
 # See the docs for more information on how to obtain one.

shiny/templates/markdown-stream/llms/ollama/app.py

@@ -9,7 +9,7 @@
 # ChatOllama() requires an Ollama model server to be running locally.
 # See the docs for more information on how to set up a local Ollama server.
 # https://posit-dev.github.io/chatlas/reference/ChatOllama.html
-chat_client = ChatOllama()
+chat_client = ChatOllama(model="llama3.2")
 
 # Some sidebar input controls to populate a prompt and trigger the stream
 with ui.sidebar():

tests/playwright/examples/example_apps.py

@@ -169,8 +169,12 @@ def wait_for_idle_app(
     )
 
 
-def validate_example(page: Page, ex_app_path: str) -> None:
-    sa: ShinyAppProc = run_shiny_app(pyshiny_root / ex_app_path, wait_for_start=True)
+def validate_example(
+    page: Page, ex_app_path: str, *, env: dict[str, str] | None = None
+) -> None:
+    sa: ShinyAppProc = run_shiny_app(
+        pyshiny_root / ex_app_path, wait_for_start=True, env=env
+    )
     app_name = os.path.basename(os.path.dirname(ex_app_path))
     short_app_path = (
         f"{os.path.basename(os.path.dirname(os.path.dirname(ex_app_path)))}/{app_name}"

tests/playwright/examples/template_provider_stubs/sitecustomize.py

@@ -0,0 +1,56 @@
+"""Stub LLM constructors before a template app starts in its child process.
+
+Python imports sitecustomize from PYTHONPATH before running ``python -m shiny``.
+This keeps the test's provider patches in the process that imports the app.
+"""
+
+import importlib
+import importlib.util
+import sys
+import types
+
+import pytest
+
+from shiny.types import Jsonifiable
+
+
+class DummyChatClient:
+    def __init__(self, *args: object, **kwargs: object) -> None:
+        pass
+
+    async def stream_async(self, *args: object, **kwargs: object) -> None:
+        raise AssertionError("Template unexpectedly called an LLM provider")
+
+    def stream(self, *args: object, **kwargs: object) -> None:
+        raise AssertionError("Template unexpectedly called an LLM provider")
+
+    async def get_state(self) -> Jsonifiable:
+        return {}
+
+    async def set_state(self, value: Jsonifiable) -> None:
+        pass
+
+
+monkeypatch = pytest.MonkeyPatch()
+
+if importlib.util.find_spec("langchain_openai") is None:
+    stub = types.ModuleType("langchain_openai")
+    stub.__dict__["ChatOpenAI"] = DummyChatClient
+    monkeypatch.setitem(sys.modules, "langchain_openai", stub)
+else:
+    langchain_openai = importlib.import_module("langchain_openai")
+    monkeypatch.setattr(langchain_openai, "ChatOpenAI", DummyChatClient)
+
+if importlib.util.find_spec("chatlas") is not None:
+    import chatlas
+
+    for name in (
+        "ChatOpenAI",
+        "ChatAnthropic",
+        "ChatGoogle",
+        "ChatOllama",
+        "ChatAzureOpenAI",
+        "ChatBedrockAnthropic",
+    ):
+        if hasattr(chatlas, name):
+            monkeypatch.setattr(chatlas, name, DummyChatClient)

tests/playwright/examples/test_shiny_create.py

@@ -9,6 +9,7 @@
 
 from shiny._main._create import (
     GithubRepoLocation,
+    find_templates,
     parse_github_arg,
     shiny_internal_templates,
     template_by_name,
@@ -86,6 +87,39 @@ def test_template_examples(page: Page, ex_app_path: str) -> None:
     validate_example(page, ex_app_path)
 
 
+def template_entrypoints() -> list[str]:
+    """All runnable bundled templates, including nested chat templates."""
+    root = Path(__file__).parents[3]
+    cases: list[str] = []
+    for template in find_templates(root / "shiny" / "templates"):
+        if template.type == "package" or template.path.parent.name == "app":
+            # The app templates already run in test_template_examples.
+            continue
+        for name in ("app.py", "app-core.py", "app-express.py"):
+            path = template.path / name
+            if path.is_file():
+                relative_path = str(path.relative_to(root))
+                cases.append(relative_path)
+    assert cases
+    return cases
+
+
+@pytest.mark.parametrize("ex_app_path", template_entrypoints())
+def test_bundled_template_starts_without_errors(page: Page, ex_app_path: str) -> None:
+    stubs = Path(__file__).parent / "template_provider_stubs"
+    pythonpath = os.pathsep.join(
+        filter(None, (str(stubs), os.environ.get("PYTHONPATH")))
+    )
+    env = {
+        "PYTHONPATH": pythonpath,
+        "OPENAI_API_KEY": "dummy",
+        "ANTHROPIC_API_KEY": "dummy",
+        "GOOGLE_API_KEY": "dummy",
+        "AZURE_OPENAI_API_KEY": "dummy",
+    }
+    validate_example(page, ex_app_path, env=env)
+
+
 app_templates = [t.id for t in shiny_internal_templates.apps]
 pkg_templates = [t.id for t in shiny_internal_templates.packages]
 assert len(app_templates) > 0