chore: return the original input path, and add a test

Signed-off-by: blam <ben@blam.sh>

packages/backend-common/src/paths.test.ts

@@ -16,7 +16,6 @@
 
 import { createMockDirectory } from '@backstage/backend-test-utils';
 import { resolveSafeChildPath } from './paths';
-import fs from 'fs/promises';
 
 describe('paths', () => {
   describe('resolveSafeChildPath', () => {
@@ -42,9 +41,9 @@ describe('paths', () => {
       );
     });
 
-    it('should resolve to the full path if the target is inside the directory', async () => {
+    it('should resolve to the full path if the target is inside the directory', () => {
       expect(resolveSafeChildPath(workspacePath, './README.md')).toEqual(
-        `${await fs.realpath(workspacePath)}/README.md`,
+        `${workspacePath}/README.md`,
       );
     });
 
@@ -60,5 +59,11 @@ describe('paths', () => {
         'Relative path is not allowed to refer to a directory outside its parent',
       );
     });
+
+    it('should not throw an error when a folder is referenced that doesnt already exist', () => {
+      expect(resolveSafeChildPath(workspacePath, 'template')).toEqual(
+        `${workspacePath}/template`,
+      );
+    });
   });
 });

packages/backend-common/src/paths.ts

@@ -72,7 +72,8 @@ export function resolveSafeChildPath(base: string, path: string): string {
     );
   }
 
-  return targetPath;
+  // Don't return the resolved path as the original could be a symlink
+  return resolvePath(base, path);
 }
 
 function resolveRealPath(path: string): string {