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diff --git a/vendor/always-assert/src/lib.rs b/vendor/always-assert/src/lib.rs
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+++ b/vendor/always-assert/src/lib.rs
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+//! Recoverable assertions, inspired by [the use of `assert()` in
+//! SQLite](https://www.sqlite.org/assert.html).
+//!
+//! `never!` and `always!` return the actual value of the condition if
+//! `debug_assertions` are disabled.
+//!
+//! Use them when terminating on assertion failure is worse than continuing.
+//!
+//! One example would be a critical application like a database:
+//!
+//! ```ignore
+//! use always_assert::never;
+//!
+//! fn apply_transaction(&mut self, tx: Transaction) -> Result<(), TransactionAborted> {
+//!     let delta = self.compute_delta(&tx);
+//!
+//!     if never!(!self.check_internal_invariant(&delta)) {
+//!         // Ok, something in this transaction messed up our internal state.
+//!         // This really shouldn't be happening, and this signifies a bug.
+//!         // Luckily, we can recover by just rejecting the transaction.
+//!         return abort_transaction(tx);
+//!     }
+//!     self.commit(delta);
+//!     Ok(())
+//! }
+//! ```
+//!
+//! Another example is assertions about non-critical functionality in usual apps
+//!
+//! ```ignore
+//! use always_assert::never;
+//!
+//! let english_message = "super app installed!"
+//! let mut local_message = localize(english_message);
+//! if never!(local_message.is_empty(), "missing localization for {}", english_message) {
+//!     // We localized all the messages but this one slipper through the cracks?
+//!     // Better to show the english one then than to fail outright;
+//!     local_message = english_message;
+//! }
+//! println!("{}", local_message);
+//! ```
+
+/// Asserts that the condition is always true and returns its actual value.
+///
+/// If the condition is true does nothing and and evaluates to true.
+///
+/// If the condition is false:
+/// * panics if `force` feature or `debug_assertions` are enabled,
+/// * logs an error if `log` feature is enabled,
+/// * evaluates to false.
+///
+/// Accepts `format!` style arguments.
+#[macro_export]
+macro_rules! always {
+    ($cond:expr) => {
+        $crate::always!($cond, "assertion failed: {}", stringify!($cond))
+    };
+
+    ($cond:expr, $fmt:literal $($arg:tt)*) => {{
+        let cond = $cond;
+        if cfg!(debug_assertions) || $crate::__FORCE {
+            assert!(cond, $fmt $($arg)*);
+        }
+        if !cond {
+            $crate::__log_error!($fmt $($arg)*);
+        }
+        cond
+    }};
+}
+
+/// Asserts that the condition is never true and returns its actual value.
+///
+/// If the condition is false does nothing and and evaluates to false.
+///
+/// If the condition is true:
+/// * panics if `force` feature or `debug_assertions` are enabled,
+/// * logs an error if `log` feature is enabled,
+/// * evaluates to true.
+///
+/// Accepts `format!` style arguments.
+///
+/// Empty condition is equivalent to false:
+///
+/// ```ignore
+/// never!("oups") ~= unreachable!("oups")
+/// ```
+#[macro_export]
+macro_rules! never {
+    (true $($tt:tt)*) => { $crate::never!((true) $($tt)*) };
+    (false $($tt:tt)*) => { $crate::never!((false) $($tt)*) };
+    () => { $crate::never!("assertion failed: entered unreachable code") };
+    ($fmt:literal $(, $($arg:tt)*)?) => {{
+        if cfg!(debug_assertions) || $crate::__FORCE {
+            unreachable!($fmt $(, $($arg)*)?);
+        }
+        $crate::__log_error!($fmt $(, $($arg)*)?);
+    }};
+
+    ($cond:expr) => {{
+        let cond = !$crate::always!(!$cond);
+        cond
+    }};
+
+    ($cond:expr, $fmt:literal $($arg:tt)*) => {{
+        let cond = !$crate::always!(!$cond, $fmt $($arg)*);
+        cond
+    }};
+}
+
+#[cfg(feature = "log")]
+#[doc(hidden)]
+pub use log::error as __log_error;
+
+#[cfg(not(feature = "log"))]
+#[doc(hidden)]
+#[macro_export]
+macro_rules! __log_error {
+    ($($tt:tt)*) => {};
+}
+
+#[doc(hidden)]
+pub const __FORCE: bool = cfg!(feature = "force");