geotiff: reject band=True/False on all read paths (#1786)

[brendancol]

Summary

Closes #1786. The non-VRT read paths only range-checked band. Because isinstance(True, int) is True in Python and True < N evaluates as 1 < N, band=True silently read band 1 and band=False read band 0 through read_to_array, _read_cog_http, read_geotiff_dask, and read_geotiff_gpu. The VRT path already rejected bools, so the contract was inconsistent across read paths.

This adds an isinstance(band, bool) guard before the range check in each non-VRT path, mirroring the VRT path's existing rejection. Uses ValueError with the same wording so all four read paths surface the same error.

Test plan

• pytest -xvs xrspatial/geotiff/tests/test_geotiff_band_bool_rejection_1786.py (12 passed including GPU)
• pytest xrspatial/geotiff/tests/test_band_validation_1673.py (Local eager band parameter accepts negative and out-of-range values silently #1673 regressions unaffected)
• pytest xrspatial/geotiff/tests/ full sweep: 10 pre-existing failures unrelated to this change (same set fails on main); 2347 passed

[Copilot]

Pull request overview

This PR fixes inconsistent band input validation across GeoTIFF read backends by rejecting band=True/band=False (which otherwise behave like 1/0 in Python) so callers don’t silently read the wrong band.

Changes:

• Add explicit bool guards for band in non-VRT read paths (read_to_array, HTTP/COG _read_cog_http, read_geotiff_dask, read_geotiff_gpu).
• Add regression tests asserting band=True/False is rejected across the main entry points.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
xrspatial/geotiff/tests/test_geotiff_band_bool_rejection_1786.py	Adds regression coverage for rejecting band=True/False across multiple read entry points.
xrspatial/geotiff/_reader.py	Rejects bool band values in read_to_array and _read_cog_http before range checks.
xrspatial/geotiff/__init__.py	Rejects bool band values in read_geotiff_dask and read_geotiff_gpu before range checks.

Comments suppressed due to low confidence (3)

xrspatial/geotiff/tests/test_geotiff_band_bool_rejection_1786.py:21

• os is imported but never used in this test module; this will fail flake8 (unused import). Remove the import or use it.

import importlib.util
import os
import uuid

xrspatial/geotiff/_reader.py:2401

• Same as the HTTP path: isinstance(band, bool) does not catch NumPy boolean scalars (np.bool_), which can still be accepted and act like 1/0. Consider rejecting np.bool_ here too to keep backend parity with _vrt.read_vrt.

            # Reject ``bool`` before the range check. ``isinstance(True, int)``
            # is True in Python and ``True < ifd_samples`` evaluates as ``1``,
            # so without this guard ``band=True`` silently reads band 1 and
            # ``band=False`` reads band 0. Matches the VRT path's existing
            # rejection so all read paths agree on the contract. See #1786.
            if isinstance(band, bool):
                raise ValueError(
                    f"band must be a non-negative int, got {band!r}")

xrspatial/geotiff/init.py:2983

• Same issue as read_geotiff_dask: np.bool_(True/False) will bypass isinstance(band, bool) and can still be treated as 1/0. Reject NumPy boolean scalars here as well to keep parity with the VRT path.

        if band is not None:
            # Reject ``bool`` up front; ``isinstance(True, int)`` is True
            # in Python so ``True < ifd_samples`` evaluates without raising
            # and silently reads band 1. Matches the VRT path's rejection
            # so all read paths agree on the contract. See #1786.
            if isinstance(band, bool):
                raise ValueError(
                    f"band must be a non-negative int, got {band!r}")

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