feat(custom-rpc): improve environment RPC (#4154)

* feat(custom-rpc): improve environment RPC

* redo

* add serialization test

* update type

* fix clippy

* rename

* chore: use serde(flatten), more explicit conversion

* untagged

* unimplement deserialization

* fixes

* snapshot

* add snapshots

* fix clippy

* serialize to string

* change serialization

* delete file

* safer serialization

* safer number or hex

---------

Co-authored-by: Daniel <daniel@chainflip.io>

state-chain/chains/src/address.rs

@@ -245,13 +245,29 @@ impl ToHumanreadableAddress for PolkadotAccountId {
 }
 
 #[cfg(feature = "std")]
-#[derive(Debug, Clone, Serialize, Deserialize)]
+#[derive(Debug, Clone, Serialize)]
+#[serde(untagged)]
+/// A type that serializes the address in a human-readable way. This can only be
+/// serialized and not deserialized.
+/// `deserialize` is not implemented for ForeignChainAddressHumanreadable
+/// because it is not possible to deserialize a human-readable address without
+/// further context around the asset and chain.
 pub enum ForeignChainAddressHumanreadable {
 	Eth(<EthereumAddress as ToHumanreadableAddress>::Humanreadable),
 	Dot(<PolkadotAccountId as ToHumanreadableAddress>::Humanreadable),
 	Btc(<ScriptPubkey as ToHumanreadableAddress>::Humanreadable),
 }
 
+#[cfg(feature = "std")]
+impl<'de> Deserialize<'de> for ForeignChainAddressHumanreadable {
+	fn deserialize<D>(_deserializer: D) -> Result<Self, D::Error>
+	where
+		D: serde::Deserializer<'de>,
+	{
+		unimplemented!("Deserialization of ForeignChainAddressHumanreadable is not implemented")
+	}
+}
+
 impl ToHumanreadableAddress for ForeignChainAddress {
 	#[cfg(feature = "std")]
 	type Humanreadable = ForeignChainAddressHumanreadable;

state-chain/custom-rpc/Cargo.toml

@@ -29,4 +29,5 @@ sp-runtime = { git = "https://github.com/chainflip-io/substrate.git", tag = "cha
 sc-client-api = { git = "https://github.com/chainflip-io/substrate.git", tag = "chainflip-monthly-2023-08+2" }
 
 [dev-dependencies]
-serde_json = "1.0.107"
+insta = { version = "1.34.0", features = ["json"] }
+serde_json = "1.0"