"""Custom rules_testing subject for java_binary/java_test executable output"""

load("@rules_testing//lib:truth.bzl", "subjects")

def _of_target(env, target):
    executable = target[DefaultInfo].files_to_run.executable.short_path
    action_subject = env.expect.that_target(target).action_generating(executable)
    public = struct(
        java_start_class = lambda: _java_start_class_subject(action_subject),
    )
    return public

def _java_start_class_subject(action):
    if action.actual.substitutions:
        return action.substitutions().get("%java_start_class%", factory = subjects.str)
    else:
        # Windows
        return action.argv().transform(
            filter = lambda e: e.startswith("java_start_class="),
            map_each = lambda e: e.split("=", 1)[1],
            desc = "java_start_class",
        ).offset(0, factory = subjects.str)

expect_that_executable = struct(
    of_target = _of_target,
)