TypeScript LSP doesn't spawn when project is in subdirectory (Module.resolve uses ctx.directory instead of resolved root) #35396

Bug summary

The TypeScript LSP server (packages/opencode/src/lsp/server.ts) fails to spawn when the TypeScript project lives in a subdirectory of the worktree (e.g. frontend-spa/ instead of the worktree root). The root is correctly resolved to the subdirectory via NearestRoot, but Module.resolve("typescript/lib/tsserver.js", ctx.directory) uses ctx.directory (the worktree root) instead of the already-resolved root, so it never finds tsserver.js.

Environment

• opencode 1.17.10 (Homebrew, macOS arm64)
• Config: "lsp": true (all built-in LSPs enabled)
• Project layout: worktree root has no package.json; frontend-spa/ has package.json with typescript ^5.0.0 and node_modules/typescript/lib/tsserver.js installed.

Steps to reproduce

1. Create a project where the TypeScript app lives in a subdirectory:

   my-worktree/
   ├── app/                  # Python backend (Pyright works)
   └── frontend-spa/
       ├── package.json      # has "typescript": "^5.0.0" in devDependencies
       ├── package-lock.json
       ├── tsconfig.json
       ├── node_modules/
       │   └── typescript/lib/tsserver.js   # EXISTS
       └── src/index.ts
   

2. Enable LSP: "lsp": true in opencode.json.
3. Run opencode debug lsp diagnostics <any .ts file in frontend-spa/src/>.

Expected behavior

The TypeScript LSP spawns and returns diagnostics (type errors, etc.).

Actual behavior

opencode debug lsp diagnostics returns {} (empty object, no diagnostics). No tsserver or typescript-language-server process is spawned. ps aux | grep tsserver shows nothing.

Meanwhile, Pyright (Python) works correctly in the same worktree because it uses which("pyright-langserver") (PATH lookup) instead of Module.resolve(..., ctx.directory).

Root cause

In packages/opencode/src/lsp/server.ts, the Typescript server definition:

export const Typescript: Info = {
  id: "typescript",
  root: NearestRoot(
    ["package-lock.json", "bun.lockb", "bun.lock", "pnpm-lock.yaml", "yarn.lock"],
    ["deno.json", "deno.jsonc"],
  ),
  extensions: [".ts", ".tsx", ".js", ".jsx", ".mjs", ".cjs", ".mts", ".cts"],
  async spawn(root, ctx) {
    const tsserver = Module.resolve("typescript/lib/tsserver.js", ctx.directory)  // ← BUG: uses ctx.directory
    if (!tsserver) return
    const bin = await Npm.which("typescript-language-server")
    if (!bin) return
    // ...
  },
}

The root parameter is correctly resolved by NearestRoot to frontend-spa/ (because that is where package-lock.json lives). However, Module.resolve is called with ctx.directory (the worktree root) instead of root. Since there is no node_modules/typescript/lib/tsserver.js at the worktree root, Module.resolve returns undefined and the LSP silently bails out.

Suggested fix

Use root (the already-resolved project root) instead of ctx.directory in the Module.resolve call:

async spawn(root, ctx) {
  const tsserver = Module.resolve("typescript/lib/tsserver.js", root)  // ← use root, not ctx.directory
  if (!tsserver) return
  // ...
}

The same pattern appears in the Astro server definition (which also calls Module.resolve("typescript/lib/tsserver.js", ctx.directory)), so it likely has the same bug.

Workaround

Create a symlink at the worktree root pointing to the subdirectory's node_modules:

ln -s frontend-spa/node_modules ./node_modules

After this, Module.resolve("typescript/lib/tsserver.js", ctx.directory) finds tsserver.js via the symlink and the TypeScript LSP spawns correctly. Verified with opencode debug lsp diagnostics:

=== TYPESCRIPT ===
{
  "/.../frontend-spa/src/__lsp_probe.ts": [
    {
      "message": "Type 'string' is not assignable to type 'number'.",
      "severity": 1,
      "code": 2322,
      "source": "typescript"
    },
    ...
  ]
}

Logs

opencode debug config shows "lsp": true and typescript is listed in enabled LSP servers. But no tsserver process is ever spawned:

$ ps aux | grep tsserver
(no output)

$ ps aux | grep pyright-langserver
iguinea  10947  ... node /opt/homebrew/bin/pyright-langserver --stdio

Impact

Any monorepo or subdirectory-layout project where the TypeScript app is not at the worktree root will have a silently broken TypeScript LSP. This is a common layout (backend + frontend split, Python + React, etc.).