python/features.bzl

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#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
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"""Allows detecting of rules_python features that aren't easily detected."""

# This is a magic string expanded by `git archive`, as set by `.gitattributes`
# See https://git-scm.com/docs/git-archive/2.29.0#Documentation/git-archive.txt-export-subst
_VERSION_PRIVATE = "$Format:%(describe:tags=true)$"

def _features_typedef():
    """Information about features rules_python has implemented.

    ::::{field} targets
    :type: dict[str, bool]

    A map of public API targets available in rules_python for feature detection
    purposes.

    :::{seealso}
    * {obj}`features.loadable_symbols`
    :::

    :::{versionadded} 1.9.0
    :::
    ::::

    ::::{field} headers_abi3
    :type: bool

    True if the {obj}`@rules_python//python/cc:current_py_cc_headers_abi3`
    target is available.

    :::{versionadded} 1.7.0
    :::
    ::::

    ::::{field} precompile
    :type: bool

    True if the precompile attributes are available.

    :::{versionadded} 0.33.0
    :::
    ::::

    ::::{field} loadable_symbols
    :type: dict[str, list[str]]

    A map of bzl paths to the list of public symbols they export.

    :::{seealso}
    * {obj}`features.targets`
    :::

    :::{versionadded} 2.2.0
    :::
    ::::

    ::::{field} py_info_venv_symlinks

    True if the `PyInfo.venv_symlinks` field is available.

    :::{versionadded} 1.5.0
    :::
    ::::

    ::::{field} uses_builtin_rules
    :type: bool

    True if the rules are using the Bazel-builtin implementation.

    :::{versionadded} 1.1.0
    :::
    ::::

    ::::{field} version
    :type: str

    The rules_python version. This is a semver format, e.g. `X.Y.Z` with
    optional trailing `-rcN`. For unreleased versions, it is an empty string.
    :::{versionadded} 0.38.0
    ::::

    ::::{field} zipapp_rules
    :type: bool

    Whether the rules_python version has the `py_zipapp_*` rules

    :::{versionadded} 1.9.0
    ::::
    """

_TARGETS = {
    "//command_line_option:build_runfile_links": True,
    "//command_line_option:enable_runfiles": True,
    "//command_line_option:extra_toolchains": True,
    "//python/api:api": True,
    "//python/api:executables": True,
    "//python/api:libraries": True,
    "//python/cc:current_py_cc_headers_abi3": True,
    "//python/cc:py_cc_toolchain": True,
    "//python/cc:py_cc_toolchain_info": True,
    "//python/cc:py_extension": True,
    "//python/config_settings:venv": True,
    "//python/entry_points:py_console_script_binary": True,
    "//python/local_toolchains:repos": True,
    "//python:defs": True,
    "//python:features": True,
    "//python:packaging": True,
    "//python:pip": True,
    "//python:proto": True,
    "//python:py_binary": True,
    "//python:py_cc_link_params_info": True,
    "//python:py_exec_tools_info": True,
    "//python:py_exec_tools_toolchain": True,
    "//python:py_executable_info": True,
    "//python:py_import": True,
    "//python:py_info": True,
    "//python:py_library": True,
    "//python:py_runtime": True,
    "//python:py_runtime_info": True,
    "//python:py_runtime_pair": True,
    "//python:py_test": True,
    "//python:repositories": True,
    "//python:versions": True,
}

_LOADABLE_SYMBOLS = {
    "//python/cc:py_extension.bzl": [
        # keep sorted
        "py_extension",
    ],
    "//python:py_info.bzl": [
        # keep sorted
        "PyInfo",
        "VenvSymlinkEntry",
        "VenvSymlinkKind",
    ],
}

features = struct(
    TYPEDEF = _features_typedef,
    # keep sorted
    headers_abi3 = True,
    loadable_symbols = _LOADABLE_SYMBOLS,
    precompile = True,
    py_info_venv_symlinks = True,
    targets = _TARGETS,
    uses_builtin_rules = False,
    version = _VERSION_PRIVATE if "$Format" not in _VERSION_PRIVATE else "",
    zipapp_rules = True,
)