//! Work counters for tests of lookup cost (feature `lookup-stats`).
//!
//! Counts fractal-heap objects read — each is one link or attribute message
//! decoded out of a dense group or dense attribute storage — so a test can
//! check that finding one name reads a handful of them, not the whole group.
//! Per thread, so tests running in parallel do not see each other's reads.
//! Without the feature the counting compiles to nothing.

#[cfg(feature = "lookup-stats")]
std::thread_local! {
    static HEAP_OBJECTS: core::cell::Cell<u64> = const { core::cell::Cell::new(0) };
}

/// Record one heap object read.
#[inline(always)]
pub(crate) fn heap_object_read() {
    #[cfg(feature = "lookup-stats")]
    HEAP_OBJECTS.with(|c| c.set(c.get() + 1));
}

/// Heap objects read on this thread since the last [`reset`].
#[cfg(feature = "lookup-stats")]
pub fn heap_objects_read() -> u64 {
    HEAP_OBJECTS.with(core::cell::Cell::get)
}

/// Zero this thread's counters.
#[cfg(feature = "lookup-stats")]
pub fn reset() {
    HEAP_OBJECTS.with(|c| c.set(0));
}