Files
Mainline/engine/display/backends/null.py
David Gwilliam e0bbfea26c refactor: consolidate pipeline architecture with unified data source system
MAJOR REFACTORING: Consolidate duplicated pipeline code and standardize on
capability-based dependency resolution. This is a significant but backwards-compatible
restructuring that improves maintainability and extensibility.

## ARCHITECTURE CHANGES

### Data Sources Consolidation
- Move engine/sources_v2.py → engine/data_sources/sources.py
- Move engine/pipeline_sources/ → engine/data_sources/
- Create unified DataSource ABC with common interface:
  * fetch() - idempotent data retrieval
  * get_items() - cached access with automatic refresh
  * refresh() - force cache invalidation
  * is_dynamic - indicate streaming vs static sources
- Support for SourceItem dataclass (content, source, timestamp, metadata)

### Display Backend Improvements
- Update all 7 display backends to use new import paths
- Terminal: Improve dimension detection and handling
- WebSocket: Better error handling and client lifecycle
- Sixel: Refactor graphics rendering
- Pygame: Modernize event handling
- Kitty: Add protocol support for inline images
- Multi: Ensure proper forwarding to all backends
- Null: Maintain testing backend functionality

### Pipeline Adapter Consolidation
- Refactor adapter stages for clarity and flexibility
- RenderStage now handles both item-based and buffer-based rendering
- Add SourceItemsToBufferStage for converting data source items
- Improve DataSourceStage to work with all source types
- Add DisplayStage wrapper for display backends

### Camera & Viewport Refinements
- Update Camera class for new architecture
- Improve viewport dimension detection
- Better handling of resize events across backends

### New Effect Plugins
- border.py: Frame rendering effect with configurable style
- crop.py: Viewport clipping effect for selective display
- tint.py: Color filtering effect for atmosphere

### Tests & Quality
- Add test_border_effect.py with comprehensive border tests
- Add test_crop_effect.py with viewport clipping tests
- Add test_tint_effect.py with color filtering tests
- Update test_pipeline.py for new architecture
- Update test_pipeline_introspection.py for new data source location
- All 463 tests pass with 56% coverage
- Linting: All checks pass with ruff

### Removals (Code Cleanup)
- Delete engine/benchmark.py (deprecated performance testing)
- Delete engine/pipeline_sources/__init__.py (moved to data_sources)
- Delete engine/sources_v2.py (replaced by data_sources/sources.py)
- Update AGENTS.md to reflect new structure

### Import Path Updates
- Update engine/pipeline/controller.py::create_default_pipeline()
  * Old: from engine.sources_v2 import HeadlinesDataSource
  * New: from engine.data_sources.sources import HeadlinesDataSource
- All display backends import from new locations
- All tests import from new locations

## BACKWARDS COMPATIBILITY

This refactoring is intended to be backwards compatible:
- Pipeline execution unchanged (DAG-based with capability matching)
- Effect plugins unchanged (EffectPlugin interface same)
- Display protocol unchanged (Display duck-typing works as before)
- Config system unchanged (presets.toml format same)

## TESTING

- 463 tests pass (0 failures, 19 skipped)
- Full linting check passes
- Manual testing on demo, poetry, websocket modes
- All new effect plugins tested

## FILES CHANGED

- 24 files modified/added/deleted
- 723 insertions, 1,461 deletions (net -738 LOC - cleanup!)
- No breaking changes to public APIs
- All transitive imports updated correctly
2026-03-16 19:47:12 -07:00

52 lines
1.3 KiB
Python

"""
Null/headless display backend.
"""
import time
class NullDisplay:
"""Headless/null display - discards all output.
This display does nothing - useful for headless benchmarking
or when no display output is needed.
"""
width: int = 80
height: int = 24
def init(self, width: int, height: int, reuse: bool = False) -> None:
"""Initialize display with dimensions.
Args:
width: Terminal width in characters
height: Terminal height in rows
reuse: Ignored for NullDisplay (no resources to reuse)
"""
self.width = width
self.height = height
def show(self, buffer: list[str], border: bool = False) -> None:
from engine.display import get_monitor
monitor = get_monitor()
if monitor:
t0 = time.perf_counter()
chars_in = sum(len(line) for line in buffer)
elapsed_ms = (time.perf_counter() - t0) * 1000
monitor.record_effect("null_display", elapsed_ms, chars_in, chars_in)
def clear(self) -> None:
pass
def cleanup(self) -> None:
pass
def get_dimensions(self) -> tuple[int, int]:
"""Get current dimensions.
Returns:
(width, height) in character cells
"""
return (self.width, self.height)