Update to 2021 edition

.changes/edition.md

@@ -0,0 +1,6 @@
+---
+"tao": patch
+---
+
+Update to 2021 edition and msrv to 1.56
+

Cargo.toml

@@ -6,7 +6,8 @@ authors = [
   "Tauri Programme within The Commons Conservancy",
   "The winit contributors"
 ]
-edition = "2018"
+edition = "2021"
+rust-version = "1.56"
 keywords = [ "windowing" ]
 license = "Apache-2.0"
 readme = "README.md"

src/lib.rs

@@ -132,6 +132,7 @@
 //! [`platform`]: platform
 //! [`raw_window_handle`]: ./window/struct.Window.html#method.raw_window_handle
 #![allow(
+  clippy::match_str_case_mismatch,
   clippy::upper_case_acronyms,
   clippy::from_over_into,
   clippy::option_map_unit_fn,

src/platform_impl/macos/observer.rs

@@ -142,7 +142,10 @@ where
   // However we want to keep that weak reference around after the function.
   std::mem::forget(info_from_raw);
 
-  stop_app_on_panic(Weak::clone(&panic_info), move || f(panic_info.0));
+  stop_app_on_panic(Weak::clone(&panic_info), move || {
+    let _ = &panic_info;
+    f(panic_info.0)
+  });
 }
 
 // begin is queued with the highest priority to ensure it is processed before other observers