Add unit suffix metadata to config classes

corrscope/config.py

@@ -24,6 +24,8 @@ __all__ = [
     "copy_config",
     "DumpableAttrs",
     "KeywordAttrs",
+    "with_units",
+    "get_units",
     "Alias",
     "Ignored",
     "DumpEnumAsStr",
@@ -222,6 +224,18 @@ class KeywordAttrs(DumpableAttrs):
         super().__init_subclass__(kw_only=True, **kwargs)
 
 
+UNIT_SUFFIX = "suffix"
+
+
+def with_units(unit, **kwargs):
+    metadata = {UNIT_SUFFIX: f" {unit}"}
+    return attr.ib(metadata=metadata, **kwargs)
+
+
+def get_units(field: attr.Attribute) -> str:
+    return field.metadata.get(UNIT_SUFFIX, "")
+
+
 @attr.dataclass
 class Alias:
     """

corrscope/corrscope.py

@@ -12,7 +12,7 @@ import attr
 
 from corrscope import outputs as outputs_
 from corrscope.channel import Channel, ChannelConfig
-from corrscope.config import KeywordAttrs, DumpEnumAsStr, CorrError
+from corrscope.config import KeywordAttrs, DumpEnumAsStr, CorrError, with_units
 from corrscope.layout import LayoutConfig
 from corrscope.renderer import MatplotlibRenderer, RendererConfig, Renderer
 from corrscope.triggers import (
@@ -51,13 +51,13 @@ class Config(
     """ Default values indicate optional attributes. """
 
     master_audio: Optional[str]
-    begin_time: float = 0
+    begin_time: float = with_units("s", default=0)
     end_time: Optional[float] = None
 
     fps: int
 
-    trigger_ms: int
-    render_ms: int
+    trigger_ms: int = with_units("ms")
+    render_ms: int = with_units("ms")
 
     # Performance
     trigger_subsampling: int = 1

corrscope/renderer.py

@@ -6,7 +6,7 @@ import attr
 import matplotlib
 import numpy as np
 
-from corrscope.config import DumpableAttrs
+from corrscope.config import DumpableAttrs, with_units
 from corrscope.layout import RendererLayout, LayoutConfig, EdgeFinder
 from corrscope.outputs import RGB_DEPTH, ByteBuffer
 from corrscope.util import coalesce
@@ -54,7 +54,7 @@ def default_color() -> str:
 class RendererConfig(DumpableAttrs, always_dump="*"):
     width: int
     height: int
-    line_width: float = 1.5
+    line_width: float = with_units("px", default=1.5)
 
     bg_color: str = "#000000"
     init_line_color: str = default_color()

tests/test_config.py

@@ -1,3 +1,4 @@
+import attr
 import pytest
 from ruamel.yaml import yaml_object
 
@@ -9,12 +10,13 @@ from corrscope.config import (
     Ignored,
     CorrError,
     CorrWarning,
+    with_units,
+    get_units,
 )
 
 # YAML Idiosyncrasies: https://docs.saltstack.com/en/develop/topics/troubleshooting/yaml_idiosyncrasies.html
 
 # Load/dump infrastructure testing
-import attr
 
 
 def test_dumpable_attrs():
@@ -52,6 +54,26 @@ def test_yaml_object():
     assert s == "!Bar {}\n"
 
 
+# Test per-field unit suffixes (used by GUI)
+
+
+def test_unit_suffix():
+    class Foo(DumpableAttrs):
+        xs: int = with_units("xs")
+        ys: int = with_units("ys", default=2)
+        no_unit: int = 3
+
+    # Assert class constructor works.
+    foo = Foo(1, 2, 3)
+    foo_default = Foo(1)
+
+    # Assert units work.
+    foo_fields = attr.fields(Foo)
+    assert get_units(foo_fields.xs) == " xs"
+    assert get_units(foo_fields.ys) == " ys"
+    assert get_units(foo_fields.no_unit) == ""
+
+
 # Dataclass dump testing