From 842d5aa60db49d8a48a1c44e0be78c9e245ad979 Mon Sep 17 00:00:00 2001
From: Bastian Venegas <r2d2@ranvier-technologies.com>
Date: Tue, 10 Mar 2026 19:03:40 -0300
Subject: [PATCH] fix: expand tilde in project path input

Replace the Effect-based expandHomePath with a plain synchronous
expandTilde using regex replacement. Apply it in resolveThreadWorkspaceCwd
(read-path for legacy data), resolveStateDir, and
normalizeProjectWorkspaceRoot (write-path, previously using expandHomePath).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---
 apps/server/src/checkpointing/Utils.ts |  5 ++++-
 apps/server/src/os-jank.test.ts        | 31 ++++++++++++++++++++++++++
 apps/server/src/os-jank.ts             | 15 ++++---------
 apps/server/src/wsServer.ts            |  4 ++--
 4 files changed, 41 insertions(+), 14 deletions(-)
 create mode 100644 apps/server/src/os-jank.test.ts

diff --git a/apps/server/src/checkpointing/Utils.ts b/apps/server/src/checkpointing/Utils.ts
index 3cd92f8510..834d00c0d2 100644
--- a/apps/server/src/checkpointing/Utils.ts
+++ b/apps/server/src/checkpointing/Utils.ts
@@ -1,5 +1,6 @@
 import { Encoding } from "effect";
 import { CheckpointRef, ProjectId, type ThreadId } from "@t3tools/contracts";
+import { expandTilde } from "../os-jank.js";
 
 export const CHECKPOINT_REFS_PREFIX = "refs/t3/checkpoints";
 
@@ -24,5 +25,7 @@ export function resolveThreadWorkspaceCwd(input: {
     return worktreeCwd;
   }
 
-  return input.projects.find((project) => project.id === input.thread.projectId)?.workspaceRoot;
+  const raw = input.projects.find((project) => project.id === input.thread.projectId)
+    ?.workspaceRoot;
+  return raw ? expandTilde(raw) : undefined;
 }
diff --git a/apps/server/src/os-jank.test.ts b/apps/server/src/os-jank.test.ts
new file mode 100644
index 0000000000..b038ed066c
--- /dev/null
+++ b/apps/server/src/os-jank.test.ts
@@ -0,0 +1,31 @@
+import * as OS from "node:os";
+import { describe, expect, it } from "vitest";
+import { expandTilde } from "./os-jank.js";
+
+describe("expandTilde", () => {
+  const home = OS.homedir();
+
+  it("expands bare ~", () => {
+    expect(expandTilde("~")).toBe(home);
+  });
+
+  it("expands ~/ prefix", () => {
+    expect(expandTilde("~/projects/foo")).toBe(`${home}/projects/foo`);
+  });
+
+  it("expands ~\\ prefix (Windows)", () => {
+    expect(expandTilde("~\\projects\\foo")).toBe(`${home}\\projects\\foo`);
+  });
+
+  it("does not expand ~ in the middle of a path", () => {
+    expect(expandTilde("/home/~user/foo")).toBe("/home/~user/foo");
+  });
+
+  it("returns absolute paths unchanged", () => {
+    expect(expandTilde("/usr/local/bin")).toBe("/usr/local/bin");
+  });
+
+  it("returns empty string unchanged", () => {
+    expect(expandTilde("")).toBe("");
+  });
+});
diff --git a/apps/server/src/os-jank.ts b/apps/server/src/os-jank.ts
index 586aca6f79..ee6225563e 100644
--- a/apps/server/src/os-jank.ts
+++ b/apps/server/src/os-jank.ts
@@ -16,21 +16,14 @@ export function fixPath(): void {
   }
 }
 
-export const expandHomePath = Effect.fn(function* (input: string) {
-  const { join } = yield* Path.Path;
-  if (input === "~") {
-    return OS.homedir();
-  }
-  if (input.startsWith("~/") || input.startsWith("~\\")) {
-    return join(OS.homedir(), input.slice(2));
-  }
-  return input;
-});
+export function expandTilde(pathStr: string): string {
+  return pathStr.replace(/^~(?=$|[\\/])/, OS.homedir());
+}
 
 export const resolveStateDir = Effect.fn(function* (raw: string | undefined) {
   const { join, resolve } = yield* Path.Path;
   if (!raw || raw.trim().length === 0) {
     return join(OS.homedir(), ".t3", "userdata");
   }
-  return resolve(yield* expandHomePath(raw.trim()));
+  return resolve(expandTilde(raw.trim()));
 });
diff --git a/apps/server/src/wsServer.ts b/apps/server/src/wsServer.ts
index 2c10b7cabe..45c386e45f 100644
--- a/apps/server/src/wsServer.ts
+++ b/apps/server/src/wsServer.ts
@@ -73,7 +73,7 @@ import {
 } from "./attachmentStore.ts";
 import { parseBase64DataUrl } from "./imageMime.ts";
 import { AnalyticsService } from "./telemetry/Services/AnalyticsService.ts";
-import { expandHomePath } from "./os-jank.ts";
+import { expandTilde } from "./os-jank.ts";
 
 /**
  * ServerShape - Service API for server lifecycle control.
@@ -298,7 +298,7 @@ export const createServer = Effect.fn(function* (): Effect.fn.Return<
     readonly command: ClientOrchestrationCommand;
   }) {
     const normalizeProjectWorkspaceRoot = Effect.fnUntraced(function* (workspaceRoot: string) {
-      const normalizedWorkspaceRoot = path.resolve(yield* expandHomePath(workspaceRoot.trim()));
+      const normalizedWorkspaceRoot = path.resolve(expandTilde(workspaceRoot.trim()));
       const workspaceStat = yield* fileSystem
         .stat(normalizedWorkspaceRoot)
         .pipe(Effect.catch(() => Effect.succeed(null)));