chore:switch to rust nightly

refactor:higher-order http method macro

we want to switch to rust nightly to be able to make use of rust
metavariable expansions as defined by RFC rust-lang/rfcs#3086 and
as tracked by rust-lang/rust#83527. other references include
rust-lang/rust#99035.

this feature was stabilized in 1.63, then unstabilized again in
rust-lang/rust#99435 and is now only available in rust nightly, awaiting
restabilization. however, the feature is stable enough for our use case,
which is why i'm going ahead and enabling it.

src-tauri/core/macros.rs

@@ -29,59 +29,25 @@ macro_rules! endpoint {
     };
 }
 
-macro_rules! get {
-    ($endpoint:expr, $endpointname:ident, $returntype:ident $(, $body:ident)? $(, [$($param:expr),+])?) => {
-        endpoint!(get, $endpoint, $endpointname, $returntype $(, $body)? $(, [$($param),+])?);
-    };
-}
-
-macro_rules! head {
-    ($endpoint:expr, $endpointname:ident, $returntype:ident $(, $body:ident)? $(, [$($param:expr),+])?) => {
-        endpoint!(head, $endpoint, $endpointname, $returntype $(, $body)? $(, [$($param),+])?);
-    };
-}
-
-macro_rules! post {
-    ($endpoint:expr, $endpointname:ident, $returntype:ident $(, $body:ident)? $(, [$($param:expr),+])?) => {
-        endpoint!(post, $endpoint, $endpointname, $returntype $(, $body)? $(, [$($param),+])?);
-    };
-}
-
-macro_rules! put {
-    ($endpoint:expr, $endpointname:ident, $returntype:ident $(, $body:ident)? $(, [$($param:expr),+])?) => {
-        endpoint!(put, $endpoint, $endpointname, $returntype $(, $body)? $(, [$($param),+])?);
-    };
-}
-
-macro_rules! delete {
-    ($endpoint:expr, $endpointname:ident, $returntype:ident $(, $body:ident)? $(, [$($param:expr),+])?) => {
-        endpoint!(delete, $endpoint, $endpointname, $returntype $(, $body)? $(, [$($param),+])?);
-    };
-}
-
-macro_rules! connect {
-    ($endpoint:expr, $endpointname:ident, $returntype:ident $(, $body:ident)? $(, [$($param:expr),+])?) => {
-        endpoint!(connect, $endpoint, $endpointname, $returntype $(, $body)? $(, [$($param),+])?);
-    };
-}
-
-macro_rules! options {
-    ($endpoint:expr, $endpointname:ident, $returntype:ident $(, $body:ident)? $(, [$($param:expr),+])?) => {
-        endpoint!(options, $endpoint, $endpointname, $returntype $(, $body)? $(, [$($param),+])?);
-    };
-}
-
-macro_rules! trace {
-    ($endpoint:expr, $endpointname:ident, $returntype:ident $(, $body:ident)? $(, [$($param:expr),+])?) => {
-        endpoint!(trace, $endpoint, $endpointname, $returntype $(, $body)? $(, [$($param),+])?);
+macro_rules! http_method {
+    ($method:ident) => {
+        macro_rules! $method {
+            ($$endpoint:expr, $$endpointname:ident, $$returntype:ident $$(, $$body:ident)? $$(, [$$($$param:expr),+])?) => {
+                endpoint!($method, $$endpoint, $$endpointname, $returntype $$(, $$body)? $$(, [$$($$param),+])?);
+            };
+        }
     };
 }
 
-macro_rules! patch {
-    ($endpoint:expr, $endpointname:ident, $returntype:ident $(, $body:ident)? $(, [$($param:expr),+])?) => {
-        endpoint!(patch, $endpoint, $endpointname, $returntype $(, $body)? $(, [$($param),+])?);
-    };
-}
+http_method!(get);
+http_method!(head);
+http_method!(post);
+http_method!(put);
+http_method!(delete);
+http_method!(connect);
+http_method!(options);
+http_method!(trace);
+http_method!(patch);
 
 macro_rules! handlers {
     ($($handler:ident),*) => {

src-tauri/lib.rs

@@ -1,3 +1,4 @@
+#![feature(macro_metavar_expr)]
 pub mod core;
 
 use clap::Parser;

src-tauri/rust-toolchain.toml

@@ -0,0 +1,2 @@
+[toolchain]
+channel = "nightly"