Fix

Author: krzkaczor

packages/ethereum-viewer/src/explorer/fetchFiles.test.ts

@@ -36,7 +36,7 @@ describe(fetchFiles.name, () => {
     await fetchFiles("optimistic.etherscan", "0x0", { fetch: f });
 
     const expectedPrefix =
-      "https://api-optimistic.etherscan.io/api?&module=contract&action=getsourcecode&address=0x0&apikey=";
+      "https://api-optimistic.etherscan.io/api?module=contract&action=getsourcecode&address=0x0&apikey=";
 
     assert(
       url?.startsWith(expectedPrefix),

packages/ethereum-viewer/src/explorer/fetchFiles.ts

@@ -42,12 +42,22 @@ export async function fetchFiles(
   }: FetchFilesOptions = {}
 ): Promise<FetchFilesResult> {
   const apiUrl = explorerApiUrls[apiName];
-  const url =
-    apiUrl +
-    "&module=contract" +
-    "&action=getsourcecode" +
-    `&address=${contractAddress}` +
-    `&apikey=${explorerApiKeys[apiName]}`;
+  let url;
+  if (apiUrl.includes("chainid=")) {
+    url =
+      apiUrl +
+      "&module=contract" +
+      "&action=getsourcecode" +
+      `&address=${contractAddress}` +
+      `&apikey=${explorerApiKeys[apiName]}`;
+  } else {
+    url =
+      apiUrl +
+      "?module=contract" +
+      "&action=getsourcecode" +
+      `&address=${contractAddress}` +
+      `&apikey=${explorerApiKeys[apiName]}`;
+  }
 
   const response = (await fetch(url)) as types.ContractSourceResponse;