feat: add the augmentation registry

pyproject.toml

@@ -41,9 +41,11 @@ keywords = [
     "offline augmentation",
     "mri",
 ]
-# smauglab has no __init__.py anywhere, so it is a PEP 420 namespace package.
-# poetry-core still walks the tree correctly; the CI build job and
-# unit_tests/test_packaging.py assert the wheel really contains every module.
+# smauglab is a regular package: every directory has an __init__.py. It used to be a
+# PEP 420 namespace package, which was dropped because the augmentation registry needs
+# a deterministic import-time population point, and because a namespace package lets a
+# stray smauglab/ elsewhere on sys.path silently merge into this one.
+# The CI build job and unit_tests/test_packaging.py assert the wheel contains every module.
 packages = [{ include = "smauglab" }]
 # The config JSONs are package data, not code, so they need listing explicitly.
 # A wheel without them is broken: smauglab resolves its default config through
@@ -258,10 +260,6 @@ python_version = "3.10"
 # incrementally rather than in one pass.
 ignore_missing_imports = true
 warn_redundant_casts = true
-# smauglab/, smauglab/transforms/ and smauglab/utils/ have no __init__.py (PEP 420,
-# see the `packages` note above), so mypy cannot derive module names without these.
-namespace_packages = true
-explicit_package_bases = true
 # Only the shipped package is gated. Tests and standalone scripts are not installed
 # and assert against literals, which reads badly to a type checker.
 exclude = ["unit_tests/", "scripts/"]

smauglab/__init__.py

@@ -0,0 +1,18 @@
+"""SmaugLab -- data augmentation strategies for MRI segmentation training.
+
+Deliberately kept free of imports from `smauglab.transforms`. Pulling the
+transforms in here would make a bare `import smauglab` drag in torch, kornia and
+batchgeneratorsv2 (several seconds), which every console-script invocation would
+then pay for. Import the subpackage you actually need:
+
+    from smauglab.transforms.gpu.transforms import AugTransformsGPU
+"""
+
+from importlib.metadata import PackageNotFoundError, version
+
+try:
+    __version__ = version("smauglab")
+except PackageNotFoundError:  # running from a source tree that was never installed
+    __version__ = "0.0.0"
+
+__all__ = ["__version__"]