Vendor things

third-party/vendor/better_scoped_tls/src/lib.rs

@@ -0,0 +1,109 @@
+//! Better scoped thread local storage.
+
+#[doc(hidden)]
+pub extern crate scoped_tls;
+
+/// See [scoped_tls::scoped_thread_local] for actual documentation.
+///
+/// This is identical as [scoped_tls::scoped_thread_local] on release builds.
+#[macro_export]
+macro_rules! scoped_tls {
+    ($(#[$attrs:meta])* $vis:vis static $name:ident: $ty:ty) => {
+        $crate::scoped_tls::scoped_thread_local!(
+            static INNER: $ty
+        );
+
+
+        $(#[$attrs])*
+        $vis static $name: $crate::ScopedKey<$ty> = $crate::ScopedKey {
+            inner: &INNER,
+            #[cfg(debug_assertions)]
+            module_path: module_path!(),
+            #[cfg(debug_assertions)]
+            name: stringify!($name),
+        };
+    };
+}
+
+/// Wrapper for [scoped_tls::ScopedKey] with better error messages.
+pub struct ScopedKey<T>
+where
+    T: 'static,
+{
+    #[doc(hidden)]
+    pub inner: &'static scoped_tls::ScopedKey<T>,
+
+    #[cfg(debug_assertions)]
+    #[doc(hidden)]
+    pub module_path: &'static str,
+
+    #[cfg(debug_assertions)]
+    #[doc(hidden)]
+    pub name: &'static str,
+}
+
+impl<T> ScopedKey<T>
+where
+    T: 'static,
+{
+    /// See [scoped_tls::ScopedKey] for actual documentation.
+    #[cfg_attr(not(debug_assertions), inline(always))]
+    pub fn set<F, R>(&'static self, t: &T, f: F) -> R
+    where
+        F: FnOnce() -> R,
+    {
+        self.inner.set(t, f)
+    }
+
+    /// See [scoped_tls::ScopedKey] for actual documentation.
+    #[cfg_attr(not(debug_assertions), inline(always))]
+    pub fn with<F, R>(&'static self, f: F) -> R
+    where
+        F: FnOnce(&T) -> R,
+    {
+        #[cfg(debug_assertions)]
+        if !self.inner.is_set() {
+            // Override panic message
+            panic!(
+                "You should perform this operation in the closure passed to `set` of {}::{}",
+                self.module_path, self.name
+            )
+        }
+
+        self.inner.with(f)
+    }
+
+    /// See [scoped_tls::ScopedKey] for actual documentation.
+    #[cfg_attr(not(debug_assertions), inline(always))]
+    pub fn is_set(&'static self) -> bool {
+        self.inner.is_set()
+    }
+}
+
+#[cfg(test)]
+mod tests {
+
+    scoped_tls!(
+        pub static TESTTLS: String
+    );
+
+    #[cfg(debug_assertions)]
+    #[test]
+    #[should_panic = "You should perform this operation in the closure passed to `set` of \
+                      better_scoped_tls::tests::TESTTLS"]
+
+    fn panic_on_with() {
+        TESTTLS.with(|s| {
+            println!("S: {}", s);
+        })
+    }
+    #[test]
+
+    fn valid() {
+        TESTTLS.set(&String::new(), || {
+            TESTTLS.with(|s| {
+                assert_eq!(*s, String::new());
+            })
+        })
+    }
+}