fix(server): worktree creation on Windows no longer fails for branch names like aux.c or a|b

apps/server/src/vcs/GitVcsDriverCore.test.ts

@@ -5097,15 +5097,18 @@ it.layer(layerTest)("GitVcsDriver core integration", (it) => {
         }),
     );
 
-    it.effect("keeps generated worktree folders short without changing long branch names", () =>
+    it.effect("keeps generated worktree folders short and valid on Windows", () =>
       Effect.gen(function* () {
+        const platform = yield* HostProcess.Platform;
         const pathService = yield* Path.Path;
         const cwd = yield* makeTmpDir();
         const { initialBranch } = yield* initRepoWithCommit(cwd);
         const worktreesDirectory = yield* makeTmpDir("custom-worktrees-");
         const driver = yield* GitVcsDriver.GitVcsDriver;
         const folders = new Set<string>();
         const branches = [
+          "fix-a-b",
+          "console",
           `feature/${"a".repeat(90)}/${"b".repeat(90)}/${"c".repeat(90)}`,
           `feature/${"a".repeat(90)}/${"b".repeat(90)}/${"d".repeat(90)}`,
           `feature/${"a".repeat(40)}/5fac`,
@@ -5115,6 +5118,27 @@ it.layer(layerTest)("GitVcsDriver core integration", (it) => {
           "界".repeat(80),
           "z".repeat(40),
           "z".repeat(41),
+          // The files ref backend cannot create or lock these branch names on Windows.
+          ...(platform === "win32"
+            ? []
+            : [
+                "fix/a<b",
+                "fix/a>b",
+                "fix/a|b",
+                "con",
+                "prn",
+                "prn.txt",
+                "aux.c",
+                "lpt0",
+                "COM¹",
+                "COM².txt",
+                "LPT³",
+                "CONIN$",
+                "CONIN$.txt",
+                "CONOUT$",
+                "CONOUT$.txt",
+                `nul.${"n".repeat(40)}`,
+              ]),
         ];
         for (const branch of branches) {
           const created = yield* driver.createWorktree(
@@ -5123,6 +5147,10 @@ it.layer(layerTest)("GitVcsDriver core integration", (it) => {
           );
           const folder = pathService.basename(created.worktree.path);
           assert.isAtMost(Buffer.byteLength(folder), 40);
+          assert.notMatch(
+            folder,
+            /[<>"|]|^(con|prn|aux|nul|com[0-9¹²³]|lpt[0-9¹²³]|conin\$|conout\$)(\.|$)/i,
+          );
           assert.equal(yield* git(created.worktree.path, ["branch", "--show-current"]), branch);
           assert.include(
             yield* git(cwd, ["-c", "core.quotePath=false", "worktree", "list", "--porcelain"]),

apps/server/src/vcs/GitVcsDriverCore.ts

@@ -4247,9 +4247,13 @@ export const makeGitVcsDriverCore = Effect.fn("makeGitVcsDriverCore")(function*
       }
       const identity = `${yield* readGitCommonDir(input.cwd)}\0${targetBranch}`;
       const hash = yield* digest.digest(Digest.sha256, new TextEncoder().encode(identity));
+      // Git refs already exclude Windows' other invalid characters and trailing dots or spaces.
+      const windowsSafeName = targetBranch
+        .replace(/[/<>"|]/g, "-")
+        .replace(/^(con|prn|aux|nul|com[0-9¹²³]|lpt[0-9¹²³]|conin\$|conout\$)(\.|$)/i, "$1-");
       // UTF-8 bytes bound UTF-16 length too, leaving room for files on Windows.
       let prefix = "";
-      for (const character of targetBranch.replace(/\//g, "-")) {
+      for (const character of windowsSafeName) {
         if (Buffer.byteLength(prefix + character) > 23) break;
         prefix += character;
       }