# Bug report: pnpm run build fails with SyntaxError: Invalid or unexpected token when pnpm is installed via mise

[pgnqukezrdxmhjso]

Bug report: pnpm run build fails with SyntaxError: Invalid or unexpected token when pnpm is installed via mise

Summary

scripts/build.ts assumes process.env.npm_execpath is a Node.js script path and feeds it to node (spawnSync(process.execPath, [packageManager, 'run', script])). When pnpm is installed via mise (or any native installer), npm_execpath points to a native Windows executable (pnpm.exe), so node tries to parse the PE binary as JavaScript and fails with SyntaxError: Invalid or unexpected token.

Environment

• OS: Windows 10/11 (zh-CN)
• Node: v24.19.0
• pnpm: 11.7.0 (installed via mise)
• dsh: 0.1.0-rc.8
• Package manager install method: mise (mise installs\pnpm\11.7.0\pnpm.exe, a ~98 MB native executable - no .cjs/.js variant present)

Repro

cd D:\data\code\deepseek-harness
pnpm run build

Observed output (abridged):

$ tsx scripts/build.ts
C:\Users\root\AppData\Local\mise\installs\pnpm\11.7.0\pnpm.exe:1
MZx@x...This program cannot be run in DOS mode.$PEd...
SyntaxError: Invalid or unexpected token

The direct equivalent of what build.ts does:

node "C:\Users\root\AppData\Local\mise\installs\pnpm\11.7.0\pnpm.exe" run build:lib

fails identically, confirming the root cause.

Root cause

scripts/build.ts (runScript):

const packageManager = process.env.npm_execpath
// ...
const result = spawnSync(process.execPath, [packageManager, 'run', script], { ... })

• process.execPath -> node.exe
• process.env.npm_execpath -> ...\pnpm\11.7.0\pnpm.exe (a native PE executable)

So the actual command executed is node "pnpm.exe" run build:lib, and node parses the PE header as source -> SyntaxError.

This works only when npm_execpath points to a JS/CJS launcher (e.g. npm's own npm-cli.js, or pnpm installed as .cjs via npm i -g pnpm). It breaks for package managers installed as native executables (mise, volta, scoop, etc.).

Suggested fix

In scripts/build.ts, detect whether npm_execpath is a native executable and spawn it directly instead of via node:

const result = /\.exe$/i.test(packageManager)
  ? spawnSync(packageManager, ['run', script], { cwd, env: environment, stdio: 'inherit' })
  : spawnSync(process.execPath, [packageManager, 'run', script], { cwd, env: environment, stdio: 'inherit' })

This preserves the existing behavior for JS launchers and fixes native binaries (Windows .exe; also consider /.(exe|cmd|bat)$/i or a more portable check). Alternatively, resolve the underlying JS entry of the package manager (e.g. via require.resolve), but the extension check is the minimal, robust fix.

Notes (possibly related)

• pnpm --version in the repo root also warns: "The 'workspaces' field in package.json is not supported by pnpm. Create a 'pnpm-workspace.yaml' file instead." - the repo does have pnpm-workspace.yaml (confirmed present), so this warning may be a separate pnpm/mise quirk worth a look.

[denial123789]

Confirmed against the current rc.8 scripts/build.ts: this is an entrypoint-class mismatch, not a TypeScript or workspace failure. The binary-looking MZ prefix plus SyntaxError: Invalid or unexpected token and the alternative .exe loader error both mean Node received native pnpm.exe as JavaScript.

A bounded recovery is to run the repository with its exact pnpm version through a JavaScript entrypoint, then prove what the nested script sees:

corepack prepare pnpm@11.7.0 --activate
corepack pnpm exec node -p "process.env.npm_execpath"
corepack pnpm install --frozen-lockfile
corepack pnpm run build

Continue only when the probe ends in .js, .cjs, or .mjs. For the upstream repair, native .exe should be spawned directly, while .cmd/.bat should not be passed to Node or papered over with shell: true; the same assumption also appears in the gate, Web snapshot, and coverage runners.

The full symptom matrix, recovery path, affected runners, and regression gates are here: https://sandbaseai.github.io/deepseek-harness-handbook/windows-standalone-pnpm.html

Canonical source-backed runbook: https://github.com/sandbaseai/deepseek-harness-handbook/blob/main/docs/en/troubleshooting/windows-standalone-pnpm-npm-execpath.md