swift_overlay_helpers.bzl

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# Licensed under the Apache License, Version 2.0 (the "License");
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"""Helper functions for users of Swift overlays."""

load("//swift/internal:providers.bzl", "SwiftOverlayCompileInfo")

def is_swift_overlay(target):
    """Returns a value indicating whether the given target is a `swift_overlay`.

    This is meant to be used by aspects that visit the `aspect_hints` of a
    target to identify the `swift_overlay` target (if present) without making
    the provider public or requiring those aspects to propagate the information
    themselves.

    Args:
        target: A `Target`; for example, an element of
            `ctx.rule.attr.aspect_hints` accessed inside an aspect.

    Returns:
        True if the target is a `swift_overlay`, otherwise False.
    """
    return SwiftOverlayCompileInfo in target