Lazy load legacy imports in skimage top module

skimage/__init__.py

@@ -1,68 +1,11 @@
 """Image Processing for Python
 
-``scikit-image`` (a.k.a. ``skimage``) is a collection of algorithms for image
+scikit-image (a.k.a. ``skimage``) is a collection of algorithms for image
 processing and computer vision.
 
 The main package of ``skimage`` only provides a few utilities for converting
-between image data types; for most features, you need to import one of the
-following subpackages:
-
-Subpackages
------------
-color
-    Color space conversion.
-data
-    Test images and example data.
-draw
-    Drawing primitives (lines, text, etc.) that operate on NumPy arrays.
-exposure
-    Image intensity adjustment, e.g., histogram equalization, etc.
-feature
-    Feature detection and extraction, e.g., texture analysis corners, etc.
-filters
-    Sharpening, edge finding, rank filters, thresholding, etc.
-graph
-    Graph-theoretic operations, e.g., shortest paths.
-io
-    Reading, saving, and displaying images and video.
-measure
-    Measurement of image properties, e.g., region properties and contours.
-metrics
-    Metrics corresponding to images, e.g. distance metrics, similarity, etc.
-morphology
-    Morphological operations, e.g., opening or skeletonization.
-restoration
-    Restoration algorithms, e.g., deconvolution algorithms, denoising, etc.
-segmentation
-    Partitioning an image into multiple regions.
-transform
-    Geometric and other transforms, e.g., rotation or the Radon transform.
-util
-    Generic utilities.
-
-Utility Functions
------------------
-img_as_float
-    Convert an image to floating point format, with values in [0, 1].
-    Is similar to `img_as_float64`, but will not convert lower-precision
-    floating point arrays to `float64`.
-img_as_float32
-    Convert an image to single-precision (32-bit) floating point format,
-    with values in [0, 1].
-img_as_float64
-    Convert an image to double-precision (64-bit) floating point format,
-    with values in [0, 1].
-img_as_uint
-    Convert an image to unsigned integer format, with values in [0, 65535].
-img_as_int
-    Convert an image to signed integer format, with values in [-32768, 32767].
-img_as_ubyte
-    Convert an image to unsigned byte format, with values in [0, 255].
-img_as_bool
-    Convert an image to boolean format, with values either True or False.
-dtype_limits
-    Return intensity limits, i.e. (min, max) tuple, of the image's dtype.
-
+between image data types; for most features, you need to import one of its
+subpackages.
 """
 
 __version__ = '0.25.0rc2.dev0'
@@ -73,7 +16,33 @@
 
 
 def __dir__():
-    return __lazy_dir__() + ['__version__']
+    """Add lazy-loaded attributes to keep consistent with `__getattr__`."""
+    patched_dir = {*globals().keys(), *__lazy_dir__()}
+    return sorted(patched_dir)
+
+
+# `attach_stub` currently ignores __all__ inside the stub file and simply
+# returns every lazy-imported object, so we need to define `__all__` again.
+__all__ = [
+    'color',
+    'data',
+    'draw',
+    'exposure',
+    'feature',
+    'filters',
+    'future',
+    'graph',
+    'io',
+    'measure',
+    'metrics',
+    'morphology',
+    'registration',
+    'restoration',
+    'segmentation',
+    'transform',
+    'util',
+    '__version__',
+]
 
 
 # Logic for checking for improper install and importing while in the source
@@ -117,68 +86,42 @@ def _raise_build_error(e):
     import sys
 
     sys.stderr.write('Partial import of skimage during the build process.\n')
-    # We are not importing the rest of the scikit during the build
+    # We are not importing the rest of the package during the build
     # process, as it may not be compiled yet
-else:
-    try:
-        from ._shared import geometry
-
-        del geometry
-    except ImportError as e:
-        _raise_build_error(e)
-
-    # Legacy imports into the root namespace; not advertised in __all__
-    from .util.dtype import (
-        dtype_limits,
-        img_as_float32,
-        img_as_float64,
-        img_as_float,
-        img_as_int,
-        img_as_uint,
-        img_as_ubyte,
-        img_as_bool,
-    )
-
-    from .util.lookfor import lookfor
-
-    from .data import data_dir
 
 
-if 'dev' in __version__:
-    # Append last commit date and hash to dev version information, if available
-
+def _try_append_commit_info(version):
+    """Append last commit date and hash to `version`, if available."""
     import subprocess
-    import os.path
+    from pathlib import Path
 
     try:
-        p = subprocess.Popen(
+        output = subprocess.check_output(
             ['git', 'log', '-1', '--format="%h %aI"'],
-            stdout=subprocess.PIPE,
-            stderr=subprocess.PIPE,
-            cwd=os.path.dirname(__file__),
+            cwd=Path(__file__).parent,
+            text=True,
         )
-    except FileNotFoundError:
+        if output:
+            git_hash, git_date = (
+                output.strip().replace('"', '').split('T')[0].replace('-', '').split()
+            )
+            version = '+'.join(
+                [tag for tag in version.split('+') if not tag.startswith('git')]
+            )
+            version += f'+git{git_date}.{git_hash}'
+
+    except (FileNotFoundError, subprocess.CalledProcessError):
         pass
     except OSError:
         pass  # If skimage is built with emscripten which does not support processes
-    else:
-        out, err = p.communicate()
-        if p.returncode == 0:
-            git_hash, git_date = (
-                out.decode('utf-8')
-                .strip()
-                .replace('"', '')
-                .split('T')[0]
-                .replace('-', '')
-                .split()
-            )
 
-            __version__ = '+'.join(
-                [tag for tag in __version__.split('+') if not tag.startswith('git')]
-            )
-            __version__ += f'+git{git_date}.{git_hash}'
+    return version
+
+
+if 'dev' in __version__:
+    __version__ = _try_append_commit_info(__version__)
+
 
-from skimage._shared.tester import PytestTester
+from skimage._shared.tester import PytestTester as _PytestTester
 
-test = PytestTester(__name__)
-del PytestTester
+test = _PytestTester(__name__)

skimage/__init__.pyi

@@ -1,4 +1,4 @@
-submodules = [
+_submodules = [
     'color',
     'data',
     'draw',
@@ -18,7 +18,7 @@ submodules = [
     'util',
 ]
 
-__all__ = submodules + ['__version__']  # noqa: F822
+__all__ = _submodules + ['__version__']  # noqa: F822
 
 from . import (
     color,
@@ -39,3 +39,17 @@ from . import (
     transform,
     util,
 )
+
+# Legacy import, not advertised in __all__
+from .util.dtype import (
+    dtype_limits,
+    img_as_float32,
+    img_as_float64,
+    img_as_float,
+    img_as_int,
+    img_as_uint,
+    img_as_ubyte,
+    img_as_bool,
+)
+from .util.lookfor import lookfor
+from .data import data_dir

skimage/color/__init__.py

@@ -1,3 +1,5 @@
+"""Color space conversion."""
+
 import lazy_loader as _lazy
 
 __getattr__, __dir__, __all__ = _lazy.attach_stub(__name__, __file__)

skimage/data/__init__.py

@@ -1,5 +1,4 @@
-"""
-Test images and datasets.
+"""Example images and datasets.
 
 A curated set of general purpose and scientific images used in tests, examples,
 and documentation.

skimage/draw/__init__.py

@@ -1,3 +1,5 @@
+"""Drawing primitives that operate on NumPy arrays, e.g., lines, text, etc."""
+
 import lazy_loader as _lazy
 
 __getattr__, __dir__, __all__ = _lazy.attach_stub(__name__, __file__)

skimage/exposure/__init__.py

@@ -1,3 +1,5 @@
+"""Image intensity adjustment, e.g., histogram equalization, etc."""
+
 import lazy_loader as _lazy
 
 __getattr__, __dir__, __all__ = _lazy.attach_stub(__name__, __file__)

skimage/feature/__init__.py

@@ -1,3 +1,5 @@
+"""Feature detection and extraction, e.g., texture analysis, corners, etc."""
+
 import lazy_loader as _lazy
 
 __getattr__, __dir__, __all__ = _lazy.attach_stub(__name__, __file__)

skimage/filters/__init__.py

@@ -1,3 +1,5 @@
+"""Sharpening, edge finding, rank filters, thresholding, etc."""
+
 import lazy_loader as _lazy
 
 __getattr__, __dir__, __all__ = _lazy.attach_stub(__name__, __file__)

skimage/graph/__init__.py

@@ -1,5 +1,5 @@
 """
-This moddule provides utilities for graph-based image processing.
+Graph-based operations, e.g., shortest paths.
 
 This includes creating adjacency graphs of pixels in an image, finding the
 central pixel in an image, finding (minimum-cost) paths across pixels, merging

skimage/io/__init__.py

@@ -1,4 +1,4 @@
-"""Utilities to read and write images in various formats."""
+"""Reading and saving of images and videos."""
 
 import warnings
 

skimage/measure/__init__.py

@@ -1,3 +1,5 @@
+"""Measurement of image properties, e.g., region properties, contours."""
+
 import lazy_loader as _lazy
 
 __getattr__, __dir__, __all__ = _lazy.attach_stub(__name__, __file__)

skimage/metrics/__init__.py

@@ -1,3 +1,5 @@
+"""Metrics corresponding to images, e.g., distance metrics, similarity, etc."""
+
 import lazy_loader as _lazy
 
 __getattr__, __dir__, __all__ = _lazy.attach_stub(__name__, __file__)

skimage/morphology/__init__.py

@@ -1,10 +1,4 @@
-"""Utilities that operate on shapes in images.
-
-These operations are particularly suited for binary images,
-although some may be useful for images of other types as well.
-
-Basic morphological operations include dilation and erosion.
-"""
+"""Morphological algorithms, e.g., closing, opening, skeletonization."""
 
 from .binary import binary_closing, binary_dilation, binary_erosion, binary_opening
 from .gray import black_tophat, closing, dilation, erosion, opening, white_tophat

skimage/restoration/__init__.py

@@ -1,4 +1,4 @@
-"""Image restoration module."""
+"""Restoration algorithms, e.g., deconvolution algorithms, denoising, etc."""
 
 import lazy_loader as _lazy
 

skimage/segmentation/__init__.py

@@ -1,4 +1,4 @@
-"""Algorithms to partition images into meaningful regions or boundaries."""
+"""Partitioning images into meaningful regions or boundaries."""
 
 from ._expand_labels import expand_labels
 from .random_walker_segmentation import random_walker

skimage/transform/__init__.py

@@ -1,4 +1,4 @@
-"""This module includes tools to transform images and volumetric data.
+"""Geometric and other transformations, e.g., rotations, Radon transform.
 
 - Geometric transformation:
   These transforms change the shape or position of an image.

skimage/util/__init__.py

@@ -1,4 +1,4 @@
-"""General utility functions.
+"""Generic utilities.
 
 This module contains a number of utility functions to work with images in general.
 """