# bazel_features when used from a WORKSPACE rather than bzlmod context requires a two-step set-up (loading bazel_features, then calling a function from inside it). # rules_go only has one-step set-up, and it would be a breaking change to require a second step. # Accordingly, we supply a polyfill implementation of bazel_features which is only used when using rules_go from a WORKSPACE file, # to avoid complicating code in rules_go itself. # We just implement the checks we've seen we actually need, and hope to delete this completely when we are in a pure-bzlmod world. _POLYFILL_BAZEL_FEATURES = """bazel_features = struct( cc = struct( find_cpp_toolchain_has_mandatory_param = {find_cpp_toolchain_has_mandatory_param}, ) ) """ def _polyfill_bazel_features_impl(rctx): # An empty string is treated as a "dev version", which is greater than anything. bazel_version = native.bazel_version or "999999.999999.999999" version_parts = bazel_version.split("-")[0].split(".") if len(version_parts) != 3: fail("invalid Bazel version '{}': got {} dot-separated segments, want 3".format(bazel_version, len(version_parts))) major_version_int = int(version_parts[0]) minor_version_int = int(version_parts[1]) find_cpp_toolchain_has_mandatory_param = major_version_int > 6 or (major_version_int == 6 and minor_version_int >= 1) rctx.file("BUILD.bazel", """exports_files(["features.bzl"]) """) rctx.file("features.bzl", _POLYFILL_BAZEL_FEATURES.format( find_cpp_toolchain_has_mandatory_param = repr(find_cpp_toolchain_has_mandatory_param), )) polyfill_bazel_features = repository_rule( implementation = _polyfill_bazel_features_impl, # Force reruns on server restarts to keep native.bazel_version up-to-date. local = True, )