From 96ef787230d57686b65547ae1e3c464fde1081f0 Mon Sep 17 00:00:00 2001
From: "odyslam.eth" <odyslam@gmail.com>
Date: Tue, 4 Jan 2022 01:51:01 +0300
Subject: [PATCH] feat: add FromStr impl for Chain (#756)

* feat: add FromStr impl for Chain

* fix(core): return error if chain not found

Co-authored-by: Georgios Konstantopoulos <me@gakonst.com>
---
 ethers-core/src/types/chain.rs | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/ethers-core/src/types/chain.rs b/ethers-core/src/types/chain.rs
index 30b85093..2a1ad903 100644
--- a/ethers-core/src/types/chain.rs
+++ b/ethers-core/src/types/chain.rs
@@ -1,6 +1,12 @@
 use std::fmt;
+use thiserror::Error;
 
 use crate::types::U256;
+use std::str::FromStr;
+
+#[derive(Debug, Clone, Error)]
+#[error("Failed to parse chain: {0}")]
+pub struct ParseChainError(String);
 
 #[derive(Debug, Clone, Copy, Eq, PartialEq)]
 pub enum Chain {
@@ -62,3 +68,28 @@ impl From<Chain> for u64 {
         u32::from(chain).into()
     }
 }
+
+impl FromStr for Chain {
+    type Err = ParseChainError;
+    fn from_str(chain: &str) -> Result<Self, Self::Err> {
+        Ok(match chain {
+            "mainnet" => Chain::Mainnet,
+            "ropsten" => Chain::Ropsten,
+            "rinkeby" => Chain::Rinkeby,
+            "goerli" => Chain::Goerli,
+            "kovan" => Chain::Kovan,
+            "xdai" => Chain::XDai,
+            "polygon" => Chain::Polygon,
+            "polygon-mumbai" => Chain::PolygonMumbai,
+            "avalanche" => Chain::Avalanche,
+            "avalanche-fuji" => Chain::AvalancheFuji,
+            "sepolia" => Chain::Sepolia,
+            "moonbeam" => Chain::Moonbeam,
+            "moonbeam-dev" => Chain::MoonbeamDev,
+            "moonriver" => Chain::Moonriver,
+            "optimism" => Chain::Optimism,
+            "optimism-kovan" => Chain::OptimismKovan,
+            _ => return Err(ParseChainError(chain.to_owned())),
+        })
+    }
+}