fix(solc): serialize metadata as raw string (#1474)

ethers-solc/src/artifacts/mod.rs

@@ -898,7 +898,7 @@ impl Serialize for LosslessMetadata {
     where
         S: Serializer,
     {
-        self.raw_metadata.serialize(serializer)
+        serializer.serialize_str(&self.raw_metadata)
     }
 }
 
@@ -920,8 +920,8 @@ impl<'de> Deserialize<'de> for LosslessMetadata {
             where
                 E: serde::de::Error,
             {
-                let raw_metadata = value.to_string();
                 let metadata = serde_json::from_str(value).map_err(serde::de::Error::custom)?;
+                let raw_metadata = value.to_string();
                 Ok(LosslessMetadata { raw_metadata, metadata })
             }
         }
@@ -2097,4 +2097,27 @@ mod tests {
             ])
         );
     }
+
+    #[test]
+    fn test_lossless_metadata() {
+        #[derive(Debug, Serialize, Deserialize)]
+        #[serde(rename_all = "camelCase")]
+        pub struct Contract {
+            #[serde(
+                default,
+                skip_serializing_if = "Option::is_none",
+                with = "serde_helpers::json_string_opt"
+            )]
+            pub metadata: Option<LosslessMetadata>,
+        }
+
+        let s = r#"{"metadata":"{\"compiler\":{\"version\":\"0.4.18+commit.9cf6e910\"},\"language\":\"Solidity\",\"output\":{\"abi\":[{\"constant\":true,\"inputs\":[],\"name\":\"owner\",\"outputs\":[{\"name\":\"\",\"type\":\"address\"}],\"payable\":false,\"stateMutability\":\"view\",\"type\":\"function\"},{\"constant\":false,\"inputs\":[{\"name\":\"newOwner\",\"type\":\"address\"}],\"name\":\"transferOwnership\",\"outputs\":[],\"payable\":false,\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"inputs\":[],\"payable\":false,\"stateMutability\":\"nonpayable\",\"type\":\"constructor\"}],\"devdoc\":{\"methods\":{\"transferOwnership(address)\":{\"details\":\"Allows the current owner to transfer control of the contract to a newOwner.\",\"params\":{\"newOwner\":\"The address to transfer ownership to.\"}}},\"title\":\"Ownable\"},\"userdoc\":{\"methods\":{}}},\"settings\":{\"compilationTarget\":{\"src/Contract.sol\":\"Ownable\"},\"libraries\":{},\"optimizer\":{\"enabled\":true,\"runs\":1000000},\"remappings\":[\":src/=src/\"]},\"sources\":{\"src/Contract.sol\":{\"keccak256\":\"0x3e0d611f53491f313ae035797ed7ecfd1dfd8db8fef8f82737e6f0cd86d71de7\",\"urls\":[\"bzzr://9c33025fa9d1b8389e4c7c9534a1d70fad91c6c2ad70eb5e4b7dc3a701a5f892\"]}},\"version\":1}"}"#;
+
+        let value: serde_json::Value = serde_json::from_str(s).unwrap();
+        let c: Contract = serde_json::from_value(value).unwrap();
+        assert_eq!(c.metadata.as_ref().unwrap().raw_metadata, "{\"compiler\":{\"version\":\"0.4.18+commit.9cf6e910\"},\"language\":\"Solidity\",\"output\":{\"abi\":[{\"constant\":true,\"inputs\":[],\"name\":\"owner\",\"outputs\":[{\"name\":\"\",\"type\":\"address\"}],\"payable\":false,\"stateMutability\":\"view\",\"type\":\"function\"},{\"constant\":false,\"inputs\":[{\"name\":\"newOwner\",\"type\":\"address\"}],\"name\":\"transferOwnership\",\"outputs\":[],\"payable\":false,\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"inputs\":[],\"payable\":false,\"stateMutability\":\"nonpayable\",\"type\":\"constructor\"}],\"devdoc\":{\"methods\":{\"transferOwnership(address)\":{\"details\":\"Allows the current owner to transfer control of the contract to a newOwner.\",\"params\":{\"newOwner\":\"The address to transfer ownership to.\"}}},\"title\":\"Ownable\"},\"userdoc\":{\"methods\":{}}},\"settings\":{\"compilationTarget\":{\"src/Contract.sol\":\"Ownable\"},\"libraries\":{},\"optimizer\":{\"enabled\":true,\"runs\":1000000},\"remappings\":[\":src/=src/\"]},\"sources\":{\"src/Contract.sol\":{\"keccak256\":\"0x3e0d611f53491f313ae035797ed7ecfd1dfd8db8fef8f82737e6f0cd86d71de7\",\"urls\":[\"bzzr://9c33025fa9d1b8389e4c7c9534a1d70fad91c6c2ad70eb5e4b7dc3a701a5f892\"]}},\"version\":1}");
+
+        let value = serde_json::to_string(&c).unwrap();
+        pretty_assertions::assert_eq!(s, value);
+    }
 }

ethers-solc/src/artifacts/serde_helpers.rs

@@ -41,7 +41,7 @@ where
 pub mod json_string_opt {
     use serde::{
         de::{self, DeserializeOwned},
-        ser, Deserialize, Deserializer, Serialize, Serializer,
+        Deserialize, Deserializer, Serialize, Serializer,
     };
 
     pub fn serialize<T, S>(value: &Option<T>, serializer: S) -> Result<S::Ok, S::Error>
@@ -50,8 +50,7 @@ pub mod json_string_opt {
         T: Serialize,
     {
         if let Some(value) = value {
-            let value = serde_json::to_string(value).map_err(ser::Error::custom)?;
+            value.serialize(serializer)
-            serializer.serialize_str(&value)
         } else {
             serializer.serialize_none()
         }

ethers-solc/src/report/mod.rs

@@ -253,7 +253,7 @@ where
     CURRENT_STATE
         .try_with(|state| {
             let scoped = state.scoped.borrow_mut();
-            f(&*scoped)
+            f(&scoped)
         })
         .unwrap_or_else(|_| f(&Report::none()))
 }