fix(files): preserve relative symlinks when duplicating entries (#6771)

* fix(files): preserve relative symlinks when duplicating entries

* test(files): verify duplicated symlink targets through daemon RPC

packages/server/src/server/daemon-e2e/filesystem.e2e.test.ts

@@ -1,5 +1,13 @@
 import { describe, test, expect, beforeEach, afterEach } from "vitest";
-import { mkdtempSync, writeFileSync, rmSync, mkdirSync, symlinkSync, readdirSync } from "fs";
+import {
+  mkdtempSync,
+  writeFileSync,
+  rmSync,
+  mkdirSync,
+  symlinkSync,
+  readdirSync,
+  readlinkSync,
+} from "fs";
 import { tmpdir } from "os";
 import path from "path";
 import { createDaemonTestContext, type DaemonTestContext } from "../test-utils/index.js";
@@ -387,6 +395,84 @@ describe("file explorer", () => {
     }
   });
 
+  test.skipIf(process.platform === "win32")(
+    "duplicating a folder keeps relative symlinks inside the copy",
+    async () => {
+      const cwd = tmpCwd();
+      try {
+        mkdirSync(path.join(cwd, "template"));
+        writeFileSync(path.join(cwd, "template", "data.txt"), "original payload\n");
+        symlinkSync("data.txt", path.join(cwd, "template", "alias.txt"));
+
+        const duplicated = await ctx.client.duplicateFileEntry({ cwd, path: "template" });
+        expect(duplicated).toMatchObject({
+          duplicatedPath: "template copy",
+          success: true,
+          error: null,
+        });
+        expect(readlinkSync(path.join(cwd, "template copy", "alias.txt"))).toBe("data.txt");
+
+        const copiedTarget = await ctx.client.readFile(cwd, "template copy/data.txt");
+        const targetWrite = await ctx.client.writeFile({
+          cwd,
+          path: "template copy/data.txt",
+          content: "copy payload\n",
+          expectedModifiedAt: copiedTarget.modifiedAt,
+          expectedRevision: copiedTarget.revision,
+        });
+        expect(targetWrite.status).toBe("written");
+        const copiedAlias = await ctx.client.readFile(cwd, "template copy/alias.txt");
+        expect(new TextDecoder().decode(copiedAlias.bytes)).toBe("copy payload\n");
+
+        const aliasWrite = await ctx.client.writeFile({
+          cwd,
+          path: "template copy/alias.txt",
+          content: "edited through copied alias\n",
+          expectedModifiedAt: copiedAlias.modifiedAt,
+          expectedRevision: copiedAlias.revision,
+        });
+        expect(aliasWrite.status).toBe("written");
+        const original = await ctx.client.readFile(cwd, "template/data.txt");
+        expect(new TextDecoder().decode(original.bytes)).toBe("original payload\n");
+        const editedCopy = await ctx.client.readFile(cwd, "template copy/data.txt");
+        expect(new TextDecoder().decode(editedCopy.bytes)).toBe("edited through copied alias\n");
+
+        const deleted = await ctx.client.deleteFileEntry({ cwd, path: "template" });
+        expect(deleted).toMatchObject({ success: true, error: null });
+        const survivingAlias = await ctx.client.readFile(cwd, "template copy/alias.txt");
+        expect(new TextDecoder().decode(survivingAlias.bytes)).toBe(
+          "edited through copied alias\n",
+        );
+      } finally {
+        rmSync(cwd, { recursive: true, force: true });
+      }
+    },
+  );
+
+  test.skipIf(process.platform === "win32")(
+    "duplicating a file symlink preserves an explicit absolute target",
+    async () => {
+      const cwd = tmpCwd();
+      const targetPath = path.join(cwd, "data.txt");
+      try {
+        writeFileSync(targetPath, "absolute target payload\n");
+        symlinkSync(targetPath, path.join(cwd, "alias.txt"));
+
+        const duplicated = await ctx.client.duplicateFileEntry({ cwd, path: "alias.txt" });
+        expect(duplicated).toMatchObject({
+          duplicatedPath: "alias copy.txt",
+          success: true,
+          error: null,
+        });
+        expect(readlinkSync(path.join(cwd, "alias copy.txt"))).toBe(targetPath);
+        const copy = await ctx.client.readFile(cwd, "alias copy.txt");
+        expect(new TextDecoder().decode(copy.bytes)).toBe("absolute target payload\n");
+      } finally {
+        rmSync(cwd, { recursive: true, force: true });
+      }
+    },
+  );
+
   test("lists directory contents", async () => {
     const cwd = tmpCwd();
 

packages/server/src/server/file-explorer/service.ts

@@ -669,6 +669,7 @@ export async function duplicateExplorerEntry({
       errorOnExist: true,
       force: false,
       preserveTimestamps: true,
+      verbatimSymlinks: true,
     });
     return { status: "ok", path: normalizeRelativePath({ root, targetPath }) };
   } catch (error) {