fix(desktop): auto-open DevTools only for UI dev, not every unpacked run

[Lumen Yang (LumenYoung)]

fix(desktop): auto-open DevTools only for UI dev, not every unpacked run

Summary

DevTools currently auto-open on every run of the desktop app that isn't a packaged build. This PR narrows that to the one scenario where auto-opening actually helps — renderer development with Vite HMR — and adds an explicit opt-out for everything else.

The problem

The trigger for auto-opening DevTools is IS_DEV, which is defined as:

const IS_DEV = !app.isPackaged;

!app.isPackaged means "not an electron-builder artifact" — but it does not mean "the user is developing the UI". Several legitimate, non-development ways of running Huabu fall into this bucket and get DevTools forced open at launch:

1. pnpm start:desktop — the script's name and documented semantics are "build everything, then run the desktop app as a user would". Yet because it ends in pnpm --filter @huabu/desktop dev (which spawns an unpacked Electron), DevTools pop up. A start script shouldn't put a debugger in your face.

2. An unpacked production build run straight from source. If someone builds the app (pnpm run build:desktop steps minus electron-builder) and runs electron . directly — for example because packaging isn't available or fails on their platform — every launch opens DevTools. This is a consumption scenario, not a development scenario.

3. Any other unpacked Electron invocation, such as CI smoke tests or sandbox-restricted environments that bypass electron-builder.

In all of these cases the main application window's first paint is immediately covered by DevTools, and the user has to close it by hand — every single launch.

What the behavior should be

Auto-opening DevTools is genuinely useful in exactly one situation: UI/renderer development, where you're iterating on the web frontend inside Electron and want the inspector available immediately. The desktop dev orchestrator (pnpm dev:desktop) already has a precise, unambiguous signal for this: it sets WEB_DEV_SERVER_URL to hand the renderer to Vite with HMR.

The fix

DevTools now auto-open only when either:

• WEB_DEV_SERVER_URL is set — i.e. the renderer is being served by Vite via the dev:desktop orchestrator. UI developers see no change in behavior.
• HUABU_DEVTOOLS=1 is set — an explicit override for anyone who wants the old behavior in any other unpacked scenario.

F12 / Ctrl+Shift+I still toggle DevTools at any time (existing shortcut handling is untouched).

if (
  IS_DEV &&
  (process.env.WEB_DEV_SERVER_URL || process.env.HUABU_DEVTOOLS === '1')
) {
  mainWindow.webContents.openDevTools();
}

Behavior matrix

Scenario	Before	After
pnpm dev:desktop (Vite HMR, real UI dev)	opens	opens (unchanged)
pnpm start:desktop (build, then run)	opens	doesn't
unpacked production build via electron .	opens	doesn't
packaged app (app.isPackaged)	doesn't	doesn't (unchanged)
any unpacked run + HUABU_DEVTOOLS=1	—	opens

Testing

• tsc --noEmit passes for @huabu/desktop.
• Verified manually: unpacked production build launches with a clean window; setting WEB_DEV_SERVER_URL restores auto-open; HUABU_DEVTOOLS=1 forces auto-open; F12 toggles as before.