Fixes a real gap discovered this session: ChatCompletion/FormatString's
"ui": {"text": [...]} return value was never rendered anywhere — no JS in
this repo ever implemented an onExecuted handler to read it, so the
retry-status banner from the previous commit was invisible in practice.
RandomChoice never returned a ui payload at all (OUTPUT_NODE was False).
- src/js/preview_text.js: read-only STRING preview widget for
ChatCompletion/FormatString/RandomChoice, mirroring ComfyUI core's own
PreviewAny node/JS extension (confirmed via the actual bundled frontend
source, not guessed) rather than inventing a new convention.
- RandomChoice: OUTPUT_NODE=True + a ui.text preview of its arbitrary-typed
output (str/number passthrough, else JSON, else str() — same fallback
chain as core's PreviewAny). IS_CHANGED still returns the raw picked
value, not the new ui-wrapped dict, so change-detection is unaffected.
- Live retry feedback: chat()/chat_structured() gain an on_status
callback, invoked at each retry boundary with a human-readable status
(_llm/retry.py's format_retry_status/format_recovered_status).
ChatCompletion wires this to ComfyUI's own PromptServer.send_progress_text
(the same first-party mechanism core's gaussian-splat/image nodes use)
rather than a hand-rolled custom event — the frontend already renders a
live "progressText" widget for it, so no additional JS was needed for
the live half of this feature.
Verified live against a real Ollama backend (docker-compose.dev.yml +
Playwright): forced a genuine refusal/retry via custom_phrases, confirmed
both the final preview widget and the live progress widget render
correctly on ChatCompletion, and confirmed FormatString/RandomChoice's
preview widgets render too. 410 tests passing.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Tests
This directory contains comprehensive pytest tests for the comfydv package.
Running Tests
# Run all tests
uv run pytest
# Run with verbose output
uv run pytest -v
# Run with coverage report
uv run pytest --cov=src/comfydv --cov-report=html
# Run specific test file
uv run pytest tests/test_format_string.py
# Run specific test class
uv run pytest tests/test_format_string.py::TestVariableExtraction
# Run specific test
uv run pytest tests/test_format_string.py::TestVariableExtraction::test_extract_simple_single_variable
# Run tests matching a pattern
uv run pytest -k "jinja2"
Coverage reports are available in htmlcov/index.html after running with --cov-report=html.
Test Coverage
Current: 75% (203 statements total, 51 missed)
format_string.py: 78% coverage__init__.py: 100% coveragecircuit_breaker.py: 68% coveragerandom_choice.py: 60% coverageutils.py: 75% coverage
Test Structure
conftest.py
Contains pytest configuration, fixtures, and mocks for ComfyUI dependencies:
- Mock ComfyUI modules (
comfy,server,folder_paths,aiohttp) - Uses
pytest_configurehook to install mocks before test collection - Provides
format_string_classfixture usingimportlibto directly load module - Fixtures for test data and class instances
- Pytest hooks for early mock installation
test_format_string.py
Comprehensive test suite for the FormatString node with 47 tests organized into classes:
- TestVariableExtraction (12 tests): Variable extraction from templates
- TestSimpleFormatting (4 tests): Python format string rendering
- TestJinja2Formatting (5 tests): Jinja2 template rendering
- TestDynamicOutputs (6 tests): Dynamic output configuration
- TestOutputConsistency (3 tests): Outputs match RETURN_TYPES/RETURN_NAMES
- TestInputTypes (4 tests): INPUT_TYPES method validation
- TestIsChanged (5 tests): Cache invalidation logic
- TestStatePersistence (2 tests): State saving/loading
- TestEdgeCases (4 tests): Error handling and edge cases
- TestTimeNowFunction (2 tests): time_now utility function
Mocking Strategy
The tests use importlib.util to directly load the format_string.py module, bypassing the package __init__.py which has ComfyUI dependencies. This allows testing without ComfyUI installation while maintaining the root __init__.py for ComfyUI extension discovery.
Writing Tests
Example test
def test_new_feature(self, format_string_class, sample_data):
"""Test that new feature works correctly."""
result = format_string_class.some_method(sample_data["name"])
assert result == expected_value
Available fixtures
format_string_class: Fresh FormatString class with reset statesample_templates: Dictionary of sample template stringssample_data: Dictionary of sample data for templates
Test naming convention
Use descriptive names: test_<what>_<condition>_<expected>
Troubleshooting
Debugging failed tests
# Run with verbose output
uv run pytest -vv --tb=long
# Run with pdb debugger
uv run pytest --pdb
Test isolation
Each test is independent. The format_string_class fixture provides a fresh instance with reset state.
Future Improvements
- Add integration tests with actual ComfyUI installation
- Add JavaScript tests for frontend functionality
- Increase coverage for circuit_breaker and random_choice nodes
- Add property-based testing with Hypothesis