luaur-common 0.1.3

Foundational data structures and flags for the luaur Luau-in-Rust toolchain.
Documentation 
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//! `FValue<T>::operator T() const` — reads the flag's current value. Reference:
//! `luau/Common/include/Luau/Common.h` (`LUAU_FORCEINLINE operator T()`).
//!
//! Modelled as `get()` rather than a `From`/`Deref` conversion: the value lives
//! behind `UnsafeCell` (so a `static` flag stays mutable), so it is returned by
//! copy, not by reference.

use crate::records::f_value::{overrides_active, FValue, FValueOverridable};

impl<T: FValueOverridable> FValue<T> {
    pub fn get(&self) -> T {
        // Fast path: no test has ever installed an override -> read the global.
        // A test that installs a `ScopedFastFlag`/`ScopedFastInt` flips
        // `OVERRIDES_ACTIVE`, and its per-thread override then shadows the
        // global for that thread only (so parallel tests don't interfere).
        if overrides_active() {
            if let Some(v) = T::override_top(self as *const FValue<T> as usize) {
                return v;
            }
        }
        unsafe { *self.value.get() }
    }
}