Fixes for pybind11-stubgen errors

[timohl]

Type

• Bug fix (non-breaking change which fixes an issue): Fixes #
• New feature (non-breaking change which adds functionality). Resolves #
• Breaking change (fix or feature that would cause existing functionality to not work as expected) Resolves #

Motivation and Context

This pull request is a follow up for/based on #6869 and contains more fixes for documentation and typing generation.
Related issues are #3052 and #6867.

Checklist:

• I have run python util/check_style.py --apply to apply Open3D code style
  to my code.
• This PR changes Open3D behavior or adds new functionality.
  • Both C++ (Doxygen) and Python (Sphinx / Google style) documentation is
    updated accordingly.
  • I have added or updated C++ and / or Python unit tests OR included test
    results (e.g. screenshots or numbers) here.
• I will follow up and update the code if CI fails.
• For fork PRs, I have selected Allow edits from maintainers.

Description

Typings are generated using:

# Create venv
python -m venv .venv
. .venv/bin/activate
pip install python/requirements.txt
pip install python/requirements_build.txt

# Build open3d and install in .venv
mkdir build && cd build
cmake ..
make -j$(nproc) && make install-pip-package

# Generate typings
pip install pybind11-stubgen
pybind11-stubgen open3d -o typings

[timohl]

I split this from #6869 because it contains changes that actually modify the bindings a bit:
Some C++ enums are exposed and the output of some __repr__ methods changes.
Also, some errors are still work in progress.

Might be easier to first merge #6869 and then discuss further changes here (with more detailed explanation from me).

[timohl]

Rebased since #6869 was merged.

I moved the integration of stubs into the python package to #6917, since it is kind of separate and might require more investigation to have it work properly.

My plan is to finish most fixes tomorrow, and then I am going to explain all changes in detail.

[timohl]

ToGoogleDocString strips any type annotations from function signatures, so every docstring::ClassMethodDocInject(...) call strips typing info.
703bead fixes this, resulting in more types displayed in documentation, as well as, more types in generated stubs.
After 703bead pybind11-stubgen produces new errors (due to now checking all previously stripped methods):

pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.core.Tensor.from_dlpack : Can't find/import 'capsule'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.core.Tensor.to_dlpack : Can't find/import 'capsule'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.KDTreeFlann.__init__ : Can't find/import 'm'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.KDTreeFlann.__init__ : Can't find/import 'n'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.KDTreeFlann.search_hybrid_vector_xd : Can't find/import 'm'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.KDTreeFlann.search_knn_vector_xd : Can't find/import 'm'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.KDTreeFlann.search_radius_vector_xd : Can't find/import 'm'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.KDTreeFlann.search_vector_xd : Can't find/import 'm'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.KDTreeFlann.set_matrix_data : Can't find/import 'm'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.KDTreeFlann.set_matrix_data : Can't find/import 'n'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.PointCloud.detect_planar_patches : Invalid expression 'open3d.geometry.KDTreeSearchParam = KDTreeSearchParamKNN with knn'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.PointCloud.estimate_covariances : Invalid expression 'open3d.geometry.KDTreeSearchParam = KDTreeSearchParamKNN with knn'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.PointCloud.estimate_normals : Invalid expression 'open3d.geometry.KDTreeSearchParam = KDTreeSearchParamKNN with knn'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.PointCloud.estimate_point_covariances : Invalid expression 'open3d.geometry.KDTreeSearchParam = KDTreeSearchParamKNN with knn'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.PointCloud.voxel_down_sample_and_trace : Can't find/import 'm'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.PointCloud.voxel_down_sample_and_trace : Can't find/import 'n'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.TriangleMesh.deform_as_rigid_as_possible : Invalid expression '<DeformAsRigidAsPossibleEnergy.Spokes: 0>'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.TriangleMesh.filter_sharpen : Invalid expression '<FilterScope.All: 0>'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.TriangleMesh.filter_smooth_laplacian : Invalid expression '<FilterScope.All: 0>'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.TriangleMesh.filter_smooth_simple : Invalid expression '<FilterScope.All: 0>'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.TriangleMesh.filter_smooth_taubin : Invalid expression '<FilterScope.All: 0>'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.TriangleMesh.simplify_vertex_clustering : Invalid expression '<SimplificationContraction.Average: 0>'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.pipelines.odometry.compute_correspondence : Invalid expression 'open3d.pipelines.odometry.OdometryOption = OdometryOption class. iteration_number_per_pyramid_level = [ 20, 10, 5, ] depth_diff_max = 0.030000 depth_min = 0.000000 depth_max'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.pipelines.odometry.compute_rgbd_odometry : Invalid expression 'open3d.camera.PinholeCameraIntrinsic = PinholeCameraIntrinsic with width = -1 and height'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.pipelines.odometry.compute_rgbd_odometry : Invalid expression '-1. Access intrinsics with intrinsic_matrix.'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.pipelines.odometry.compute_rgbd_odometry : Invalid expression 'open3d.pipelines.odometry.OdometryOption = OdometryOption class. iteration_number_per_pyramid_level = [ 20, 10, 5, ] depth_diff_max = 0.030000 depth_min = 0.000000 depth_max'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.pipelines.registration.Feature.data. : Can't find/import 'm'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.pipelines.registration.Feature.data. : Can't find/import 'n'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.pipelines.registration.Feature.data. : Can't find/import 'm'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.pipelines.registration.Feature.data. : Can't find/import 'n'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.pipelines.registration.registration_colored_icp : Invalid expression 'open3d.pipelines.registration.TransformationEstimationForColoredICP = TransformationEstimationForColoredICP with lambda_geometric'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.pipelines.registration.registration_colored_icp : Invalid expression 'open3d.pipelines.registration.ICPConvergenceCriteria = ICPConvergenceCriteria class with relative_fitness'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.pipelines.registration.registration_fgr_based_on_correspondence : Invalid expression 'open3d.pipelines.registration.FastGlobalRegistrationOption = FastGlobalRegistrationOption class with division_factor= tuple_test={} use_absolute_scale=1.4 decrease_mu=false maximum_correspondence_distance=true iteration_number=0.025 tuple_scale=64 maximum_tuple_count'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.pipelines.registration.registration_fgr_based_on_feature_matching : Invalid expression 'open3d.pipelines.registration.FastGlobalRegistrationOption = FastGlobalRegistrationOption class with division_factor= tuple_test={} use_absolute_scale=1.4 decrease_mu=false maximum_correspondence_distance=true iteration_number=0.025 tuple_scale=64 maximum_tuple_count'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.pipelines.registration.registration_generalized_icp : Invalid expression 'open3d.pipelines.registration.TransformationEstimationForGeneralizedICP = TransformationEstimationForGeneralizedICP with epsilon'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.pipelines.registration.registration_generalized_icp : Invalid expression 'open3d.pipelines.registration.ICPConvergenceCriteria = ICPConvergenceCriteria class with relative_fitness'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.pipelines.registration.registration_icp : Invalid expression 'open3d.pipelines.registration.ICPConvergenceCriteria = ICPConvergenceCriteria class with relative_fitness'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.pipelines.registration.registration_ransac_based_on_correspondence : Invalid expression 'open3d.pipelines.registration.RANSACConvergenceCriteria = RANSACConvergenceCriteria class with max_iteration'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.pipelines.registration.registration_ransac_based_on_feature_matching : Invalid expression 'open3d.pipelines.registration.RANSACConvergenceCriteria = RANSACConvergenceCriteria class with max_iteration'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.t.pipelines.slam.Model.track_frame_to_model : Invalid expression '<Method.PointToPlane: 0>'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.t.pipelines.slam.Model.track_frame_to_model : Invalid expression '[OdometryConvergenceCriteria[max_iteration=6, relative_rmse=1.000000e-06, relative_fitness=1.000000e-06]., OdometryConvergenceCriteria[max_iteration=3, relative_rmse=1.000000e-06, relative_fitness=1.000000e-06]., OdometryConvergenceCriteria[max_iteration=1, relative_rmse=1.000000e-06, relative_fitness=1.000000e-06].]'
pybind11_stubgen - [WARNING] Enum-like str representations were found with no matching mapping to the enum class location.
Use `--enum-class-locations` to specify full path to the following enum(s):
 - DeformAsRigidAsPossibleEnergy
 - SimplificationContraction
 - Method
 - FilterScope
pybind11_stubgen - [WARNING] Raw C++ types/values were found in signatures extracted from docstrings.
Please check the corresponding sections of pybind11 documentation to avoid common mistakes in binding code:
 - https://pybind11.readthedocs.io/en/latest/advanced/misc.html#avoiding-cpp-types-in-docstrings
 - https://pybind11.readthedocs.io/en/latest/advanced/functions.html#default-arguments-revisited

I fixed most of these errors so now the remaining pybind11-stubgen errors are:

pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.core.Tensor.from_dlpack : Can't find/import 'capsule'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.core.Tensor.to_dlpack : Can't find/import 'capsule'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.KDTreeFlann.__init__ : Can't find/import 'm'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.KDTreeFlann.__init__ : Can't find/import 'n'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.KDTreeFlann.search_hybrid_vector_xd : Can't find/import 'm'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.KDTreeFlann.search_knn_vector_xd : Can't find/import 'm'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.KDTreeFlann.search_radius_vector_xd : Can't find/import 'm'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.KDTreeFlann.search_vector_xd : Can't find/import 'm'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.KDTreeFlann.set_matrix_data : Can't find/import 'm'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.KDTreeFlann.set_matrix_data : Can't find/import 'n'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.PointCloud.voxel_down_sample_and_trace : Can't find/import 'm'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.geometry.PointCloud.voxel_down_sample_and_trace : Can't find/import 'n'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.pipelines.registration.Feature.data. : Can't find/import 'm'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.pipelines.registration.Feature.data. : Can't find/import 'n'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.pipelines.registration.Feature.data. : Can't find/import 'm'
pybind11_stubgen - [  ERROR] In open3d.cpu.pybind.pipelines.registration.Feature.data. : Can't find/import 'n'

pybind11-stubgen seems to have problems with numpy annotations using m and n as dimensions, e.g., produced by Eigen::MatrixXd.
Also capsule seems to be problematic.

[timohl]

I do not know how to fix the last two errors right now, so for now I will have to leave them and maybe fix them later.
Now I will try to summarize and describe the changes, so review will be easier.

[timohl]

All changes can be summarized as follows:

• Fixed ToGoogleDocString to not strip type information (see 703bead)
• Fixed parser bug when docstrings contain , (20c1855, see strange default value for robust param in 0.18.0 docs)
• Change __repr__ methods to output valid constructor call. Otherwise, stubs contain invalid code in default values.
• Using py::arg_v for enums in default values. Otherwise, enums will be represented as <[Enum.Name]: [Value]> which is invalid in python.
• Added missing enum/class binding for DtypeCode, TextureHandle

[timohl]

Fixed the last remaining errors:

• Defining capsule = typing.Any (until types.CapsuleType will be available in 3.13, see Expose capsule type in types module python/cpython#109599)
• Defining m and n as typing.TypeVar

Now pybind11-stubgen is able to run without any errors.
Maybe a CI workflow with IGNORE_STUBGEN_ERRORS=OFF could be added in the future when #6917 is resolved to prevent any regression.