carbon-lang/testing/file_test/rules.bzl

# Part of the Carbon Language project, under the Apache License v2.0 with LLVM
# Exceptions. See /LICENSE for license information.
# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

"""Rules for building file tests.

file_test uses the tests_as_input_file rule to transform test dependencies into
a file which can be accessed as a list. This avoids long argument parsing.
"""

load("@rules_cc//cc:defs.bzl", "cc_test")
load("//bazel/cc_toolchains:defs.bzl", "cc_env")
load("//bazel/manifest:defs.bzl", "manifest", "manifest_as_cpp")

def file_test(
        name,
        tests,
        srcs = [],
        deps = [],
        data = [],
        args = [],
        prebuilt_binary = None,
        **kwargs):
    """Generates tests using the file_test base.

    There will be one main test using `name` that can be sharded, and includes
    all files. Additionally, per-file tests will be generated as
    `name.file_path`; these per-file tests will be manual.

    Args:
      name: The base name of the tests.
      tests: The list of test files to use as data, typically a glob.
      srcs: Passed to cc_test.
      deps: Passed to cc_test.
      data: Passed to cc_test.
      args: Passed to cc_test.
      prebuilt_binary: If set, specifies a prebuilt test binary to use instead
                       of building a new one.
      **kwargs: Passed to cc_test.
    """

    # Ensure tests are always a filegroup for tests_as_input_file_rule.
    if prebuilt_binary:
        # TODO: The prebuilt_binary support is only used by explorer. We should
        # remove this once explorer is removed, and think about better factoring
        # approaches if we need it later for toolchain.
        tests_file = "{0}.tests".format(name)
        manifest(
            name = tests_file,
            srcs = tests,
            testonly = 1,
        )
        args = ["--explorer_test_targets_file=$(rootpath :{0})".format(tests_file)] + args

        native.sh_test(
            name = name,
            srcs = srcs + [prebuilt_binary],
            deps = deps,
            data = [":" + tests_file] + tests + data,
            args = args,
            env = cc_env(),
            **kwargs
        )
    else:
        manifest_cpp = "{0}_autogen_manifest.cpp".format(name)
        manifest_as_cpp(
            name = manifest_cpp,
            var_name = "CarbonFileTestManifest",
            srcs = tests,
            testonly = 1,
        )
        cc_test(
            name = name,
            srcs = srcs + [":" + manifest_cpp],
            deps = deps + ["//testing/file_test:manifest_impl"],
            data = tests + data,
            args = args,
            env = cc_env(),
            **kwargs
        )