hypothesis-geometry 0.8.1

hypothesis strategies for geometric objects (points, polygons, etc.).

hypothesis_geometry

In what follows

• python is an alias for python3.5 or any later version (python3.6 and so on),
• pypy is an alias for pypy3.5 or any later version (pypy3.6 and so on).

Installation

Install the latest pip & setuptools packages versions:

• with CPython

  python -m pip install --upgrade pip setuptools
  

• with PyPy

  pypy -m pip install --upgrade pip setuptools
  

User

Download and install the latest stable version from PyPI repository:

• with CPython

  python -m pip install --upgrade hypothesis_geometry
  

• with PyPy

  pypy -m pip install --upgrade hypothesis_geometry
  

Developer

Download the latest version from GitHub repository

git clone https://github.com/lycantropos/hypothesis_geometry.git
cd hypothesis_geometry

Install dependencies:

• with CPython

  python -m pip install --force-reinstall -r requirements.txt
  

• with PyPy

  pypy -m pip install --force-reinstall -r requirements.txt
  

Install:

• with CPython

  python setup.py install
  

• with PyPy

  pypy setup.py install
  

Usage

With setup

>>> from hypothesis import strategies
>>> from hypothesis_geometry import planar
>>> min_coordinate, max_coordinate = -100, 100
>>> coordinates_type = int
>>> coordinates = strategies.integers(min_coordinate, max_coordinate)
>>> import warnings
>>> from hypothesis.errors import NonInteractiveExampleWarning
>>> # ignore hypothesis warnings caused by `example` method call
... warnings.filterwarnings('ignore', category=NonInteractiveExampleWarning)

let's take a look at what can be generated and how.

Points

>>> points = planar.points(coordinates)
>>> point = points.example()
>>> isinstance(point, tuple)
True
>>> len(point) == 2
True
>>> all(isinstance(coordinate, coordinates_type) for coordinate in point)
True
>>> all(min_coordinate <= coordinate <= max_coordinate for coordinate in point)
True

Segments

>>> segments = planar.segments(coordinates)
>>> segment = segments.example()
>>> isinstance(segment, tuple)
True
>>> len(segment) == 2
True
>>> all(isinstance(endpoint, tuple) for endpoint in segment)
True
>>> all(len(endpoint) == 2 for endpoint in segment)
True
>>> all(all(isinstance(coordinate, coordinates_type) 
...         for coordinate in endpoint)
...     for endpoint in segment)
True
>>> all(all(min_coordinate <= coordinate <= max_coordinate 
...         for coordinate in endpoint)
...     for endpoint in segment)
True

Polylines

>>> min_size, max_size = 5, 10
>>> polylines = planar.polylines(coordinates, 
...                              min_size=min_size,
...                              max_size=max_size)
>>> polyline = polylines.example()
>>> isinstance(polyline, list)
True
>>> min_size <= len(polyline) <= max_size
True
>>> all(isinstance(vertex, tuple) for vertex in polyline)
True
>>> all(len(vertex) == 2 for vertex in polyline)
True
>>> all(all(isinstance(coordinate, coordinates_type)
...         for coordinate in vertex)
...     for vertex in polyline)
True
>>> all(all(min_coordinate <= coordinate <= max_coordinate 
...         for coordinate in vertex)
...     for vertex in polyline)
True

Contours

>>> min_size, max_size = 5, 10
>>> contours = planar.contours(coordinates, 
...                            min_size=min_size,
...                            max_size=max_size)
>>> contour = contours.example()
>>> isinstance(contour, list)
True
>>> min_size <= len(contour) <= max_size
True
>>> all(isinstance(vertex, tuple) for vertex in contour)
True
>>> all(len(vertex) == 2 for vertex in contour)
True
>>> all(all(isinstance(coordinate, coordinates_type)
...         for coordinate in vertex)
...     for vertex in contour)
True
>>> all(all(min_coordinate <= coordinate <= max_coordinate
...         for coordinate in vertex)
...     for vertex in contour)
True

also planar.concave_contours & planar.convex_contours options are available.

Polygons

>>> min_size, max_size = 5, 10
>>> min_holes_size, max_holes_size = 1, 3
>>> min_hole_size, max_hole_size = 4, 8
>>> polygons = planar.polygons(coordinates, 
...                            min_size=min_size,
...                            max_size=max_size,
...                            min_holes_size=min_holes_size,
...                            max_holes_size=max_holes_size,
...                            min_hole_size=min_hole_size,
...                            max_hole_size=max_hole_size)
>>> polygon = polygons.example()
>>> isinstance(polygon, tuple)
True
>>> len(polygon) == 2
True
>>> border, holes = polygon
>>> isinstance(border, list)
True
>>> all(isinstance(hole, list) for hole in holes)
True
>>> min_size <= len(border) <= max_size
True
>>> min_holes_size <= len(holes) <= max_holes_size
True
>>> all(min_hole_size <= len(hole) <= max_hole_size for hole in holes)
True
>>> contours = [border, *holes]
>>> all(isinstance(vertex, tuple)
...     for contour in contours
...     for vertex in contour)
True
>>> all(len(vertex) == 2
...     for contour in contours
...     for vertex in contour)
True
>>> all(all(isinstance(coordinate, coordinates_type)
...         for coordinate in vertex)
...     for contour in contours
...     for vertex in contour)
True
>>> all(all(min_coordinate <= coordinate <= max_coordinate
...         for coordinate in vertex)
...     for contour in contours
...     for vertex in contour)
True

Caveats

• Strategies may be slow depending on domain, so it may be necessary to add HealthCheck.filter_too_much, HealthCheck.too_slow in suppress_health_check and set deadline to None.

• Unbounded floating point strategies for coordinates (like hypothesis.strategies.floats with unset min_value/max_value) do not play well with bounded sizes and may cause a lot of searching iterations with no success, so it is recommended to use bounded floating point coordinates with bounded sizes or unbounded coordinates with unbounded sizes.

• decimal.Decimal coordinates are not supported, because they seem to be too hard to work with correctly (e.g. sometimes self-intersecting contours arise), so it is suggested to use float or fractions.Fraction instead.

Development

Bumping version

Preparation

Install bump2version.

Pre-release

Choose which version number category to bump following semver specification.

Test bumping version

bump2version --dry-run --verbose $CATEGORY

where $CATEGORY is the target version number category name, possible values are patch/minor/major.

Bump version

bump2version --verbose $CATEGORY

This will set version to major.minor.patch-alpha.

Release

Test bumping version

bump2version --dry-run --verbose release

Bump version

bump2version --verbose release

This will set version to major.minor.patch.

Running tests

Install dependencies:

• with CPython

  python -m pip install --force-reinstall -r requirements-tests.txt
  

• with PyPy

  pypy -m pip install --force-reinstall -r requirements-tests.txt
  

Plain

pytest

Inside Docker container:

• with CPython

  docker-compose --file docker-compose.cpython.yml up
  

• with PyPy

  docker-compose --file docker-compose.pypy.yml up
  

Bash script (e.g. can be used in Git hooks):

• with CPython

  ./run-tests.sh
  

  or

  ./run-tests.sh cpython
  

• with PyPy

  ./run-tests.sh pypy
  

PowerShell script (e.g. can be used in Git hooks):

• with CPython

  .\run-tests.ps1
  

  or

  .\run-tests.ps1 cpython
  

• with PyPy

  .\run-tests.ps1 pypy