Cleanup internals (#101)

* fix: const_err is not a hard error

See: rust-lang/rust#71800

* fix: lints

* fix: macro doctests

* fix: renamed lint

* fix: restore use of enum variant

Cargo.toml

@@ -22,7 +22,7 @@ thiserror = "1.0"
 trybuild = { version = "1.0.19", features = ["diff"] }
 backtrace = "0.3.46"
 anyhow = "1.0.28"
-syn = { version = "1.0", features = ["full"] }
+syn = { version = "2.0", features = ["full"] }
 pyo3 = { version = "0.13", default-features = false, features = ["auto-initialize"] }
 
 [dependencies]

src/lib.rs

@@ -332,11 +332,11 @@
 #![warn(
     missing_debug_implementations,
     missing_docs,
-    missing_doc_code_examples,
+    // FIXME: this lint is currently nightly only
+    rustdoc::missing_doc_code_examples,
     rust_2018_idioms,
     unreachable_pub,
     bad_style,
-    const_err,
     dead_code,
     improper_ctypes,
     non_shorthand_field_patterns,

tests/test_context.rs

@@ -21,7 +21,7 @@ macro_rules! context_type {
         #[derive(Debug)]
         struct $name {
             message: &'static str,
-            drop: DetectDrop,
+            _drop: DetectDrop,
         }
 
         impl Display for $name {
@@ -74,15 +74,15 @@ fn make_chain() -> (Report, Dropped) {
     let mid = Err::<(), LowLevel>(low)
         .wrap_err(MidLevel {
             message: "failed to load config",
-            drop: DetectDrop::new(&dropped.mid),
+            _drop: DetectDrop::new(&dropped.mid),
         })
         .unwrap_err();
 
     // impl Report for Result<T, Error>
     let high = Err::<(), Report>(mid)
         .wrap_err(HighLevel {
             message: "failed to start server",
-            drop: DetectDrop::new(&dropped.high),
+            _drop: DetectDrop::new(&dropped.high),
         })
         .unwrap_err();
 

tests/test_macros.rs

@@ -62,15 +62,15 @@ fn test_temporaries() {
         // time it's done evaluating, those will stick around until the
         // semicolon, which is on the other side of the await point, making the
         // enclosing future non-Send.
-        Ready(Some(eyre!("..."))).await;
+        let _ = Ready(Some(eyre!("..."))).await;
     });
 
     fn message(cell: Cell<&str>) -> &str {
         cell.get()
     }
 
     require_send_sync(async {
-        Ready(Some(eyre!(message(Cell::new("..."))))).await;
+        let _ = Ready(Some(eyre!(message(Cell::new("..."))))).await;
     });
 }