Type-hint coverage: ~89% overall, remaining gaps in ImageCore, Sources, blocks, bin #60

Tracks type-hint coverage of src/machinevisiontoolbox. Last refreshed 2026-10-17.

An AST audit counts annotated parameters (excluding self/cls) and return types over every function and method under src/machinevisiontoolbox, including subpackages (bin/, blocks/).

Correction to the original report. The 2026-08-10 figures (54.3% params, 74.9% average) were wrong: the audit script counted self/cls, which are never annotated. Recomputed without them on 2026-10-03 the figure was already about 86.8% params / 95.6% returns. So the overall picture is that coverage was always mostly good, and the real gaps are a few specific modules, not a broad shortfall. Per-module parameter coverage now:

Remaining work

Annotated means present, not correct: see #40 for running mypy in CI so annotations are actually checked.

Largest gaps by unannotated parameters:

• ImageCore.py: 61 of 142 parameters
• Sources.py: 50 of 180
• blocks/camera.py: 32 of 32 (no annotations at all)
• bin/ scripts (mvtbtool, tagtool, bagtool, imtool, _iminteractive): almost entirely unannotated
• Camera.py (14), ImagePointFeatures.py (12), ImageConstants.py (10), ImageBlobs.py (10), ImageIO.py (7)
• Return annotations: a handful of functions across ImageConstants.py, ImageProcessing.py, ImageMultiview.py, Sources.py

Modules now at or near 100%: ImageSpatial, ImageMorph, ImageTensor, ImageRegionFeatures, VisualServo, BundleAdjust, PointCloud, Kernel, ImageFiducials.

Guidelines for contributions

• Use modern syntax: X | Y, X | None, list[X]; not Union, Optional, List.
• Arrays: use ArrayLike from machinevisiontoolbox.mvtb_types for arguments. (There is no NDArray alias there yet.)
• Type hints replace :type:/:rtype: in docstrings; keep those only where array shape adds information.
• Annotation-only changes please: no behaviour changes in the same PR.
• The project's type checker is intended to be mypy (see Adopt mypy (as in RTB): 534 errors to ratchet down, not yet run in CI #40), not Pyright.

No architectural changes are needed, just incremental annotation additions per module.