fix forward slash problem in files path

ui/address/contract/ContractSourceCode.tsx

@@ -6,6 +6,7 @@ import type { SmartContract } from 'types/api/contract';
 
 import LinkInternal from 'ui/shared/LinkInternal';
 import CodeEditor from 'ui/shared/monaco/CodeEditor';
+import formatFilePath from 'ui/shared/monaco/utils/formatFilePath';
 
 interface Props {
   data: string;
@@ -37,8 +38,10 @@ const ContractSourceCode = ({ data, hasSol2Yml, address, isViper, filePath, addi
   ) : null;
 
   const editorData = React.useMemo(() => {
-    const defaultName = isViper ? 'index.vy' : 'index.sol';
-    return [ { file_path: filePath || defaultName, source_code: data }, ...(additionalSource || []) ];
+    const defaultName = isViper ? '/index.vy' : '/index.sol';
+    return [
+      { file_path: formatFilePath(filePath || defaultName), source_code: data },
+      ...(additionalSource || []).map((source) => ({ ...source, file_path: formatFilePath(source.file_path) })) ];
   }, [ additionalSource, data, filePath, isViper ]);
 
   return (

ui/shared/monaco/utils/composeFileTree.ts

@@ -2,17 +2,7 @@ import type { File, FileTree } from '../types';
 
 import sortFileTree from './sortFileTree';
 
-const stripLeadingSlash = (str: string) => {
-  if (str[0] === '.' && str[1] === '/') {
-    return str.slice(2);
-  }
-
-  if (str[0] === '/') {
-    return str.slice(1);
-  }
-
-  return str;
-};
+const stripLeadingSlash = (str: string) => str[0] === '/' ? str.slice(1) : str;
 
 export default function composeFileTree(files: Array<File>) {
   const result: FileTree = [];

ui/shared/monaco/utils/formatFilePath.ts

+// ensure that path always starts with /
+export default function formatFilePath(path: string) {
+  if (path[0] === '.' && path[1] === '/') {
+    return path.slice(1);
+  }
+
+  if (path[0] === '/') {
+    return path;
+  }
+
+  return '/' + path;
+}