fix: MetadataError::RoundtripError now requires Send + Sync (#396)

* add anyhow to dev dependencies

BREAKING CHANGE: error types not Send + Sync
are now incompatible with metadata round trips.

Author: molpopgen

Cargo.toml

@@ -29,6 +29,7 @@ tskit-derive = {version = "0.2.0", path = "tskit-derive", optional = true}
 mbox = "0.6.0"
 
 [dev-dependencies]
+anyhow = {version = "1.0.66"}
 clap = {version = "~3.2.8", features = ["derive"]}
 serde = {version = "1.0.118", features = ["derive"]}
 serde-pickle = "1.1.0"

src/error.rs

@@ -142,4 +142,14 @@ mod test {
             panic!();
         }
     }
+
+    #[test]
+    fn test_anyhow_compatability() {
+        fn foo() -> anyhow::Result<crate::TableCollection> {
+            let tables = crate::TableCollection::new(1.0)?;
+            Ok(tables)
+        }
+
+        let _ = foo().unwrap();
+    }
 }

src/metadata.rs

@@ -246,7 +246,7 @@ pub enum MetadataError {
     #[error("{}", *value)]
     RoundtripError {
         #[from]
-        value: Box<dyn std::error::Error>,
+        value: Box<dyn std::error::Error + Send + Sync>,
     },
 }