Vendored copy of @gradio/preview, the Vite layer behind gradio cc dev and gradio cc build.

It is vendored because the upstream package is tightly coupled to the Gradio app bundle it drives, and the two have drifted: several dev-server problems can only be fixed from inside this package (the virtual:cc-init module, the index-html bootstrap, the build entry composition, the Vite version it ships with).

• 0.17.1 (Gradio 6.9+/6.28 era) ships the right Vite (vite ^8, @sveltejs/vite-plugin-svelte ^7) but has the dev-bootstrap bugs listed below.
• 0.15.2 (Gradio <= 6.8 era) boots the shared-runtime app correctly but depends on vite ^7 / @sveltejs/vite-plugin-svelte ^6, which is incompatible with this repo's vite 8 (rolldown) toolchain — it fails with Missing field 'moduleType'.

So this package takes the 0.17.1 source (for the vite 8 deps + fixes) and makes it work across both Gradio generations via detect_generation.

Re-syncing means diffing src/ against that path upstream, taking their changes and re-applying the fixes below, then pnpm -F @modelscope-studio/gradio-preview build.

1. Dev bootstrap works on every Gradio generation. The dev globals (__GRADIO_DEV__, __GRADIO__SERVER_PORT__, __GRADIO__CC__, __GRADIO__CC__RUNTIMES__) are injected into the page via transformIndexHtml. Upstream only rewrites a "_NORMAL_" marker inside the built app bundle, which silently misses when the minifier emits it as a template literal (Gradio 6.23) and does not exist at all in Gradio <= 6.8 — in both cases the app falls back to its own origin and asks the dev server for /config, which answers with HTML.

2. The Jinja template is neutralised. The dev server hands index.html to the browser unrendered, so <base href="{{ base_url ... }}"> (Gradio 6.9+) would make every relative asset URL resolve against the raw template text (blank page), and the inline window.gradio_* = {{ ... }}; assignments are syntax errors.

3. Backend-owned routes are proxied (theme.css, manifest.json, gradio_api, custom_component). theme.css is resolved against the document, so without this the app loads a stylesheet with zero rules and renders with no Gradio CSS variables at all.

4. Generation detection (detect_generation), driving both dev and build:

   • shared (Gradio <= 6.8) — the app exposes its runtime under assets/svelte/*; components resolve svelte to it and share one instance. __GRADIO__CC__RUNTIMES__ is left empty and no per-component runtime entry is built.
   • bridge (Gradio >= ~6.9) — the runtime is inlined in the app bundle; components bring their own and are mounted through svelte_runtime_entry.js.

   Mixing two runtime instances is what makes a snippet blow up with Cannot read properties of null (reading 'nodes') as soon as rendering leaves the synchronous mount call.

5. Pre-transform error is no longer swallowed. Upstream drops it from the logger, which turns a failing module into an app that hangs with no output.

detect_generation picks the right dev/build strategy, but it cannot fix version-contract mismatches between the components and the Gradio app they run against. When changing the target Gradio version, also align, in the repo root and frontend/:

• svelte must match the version Gradio bundles for the shared runtime (.../gradio/templates/frontend/assets/svelte/svelte_package.json.js). A newer compiler emits $$restProps excludes as a Set while an older runtime expects an array, which throws target.exclude.includes is not a function. Pin it repo-wide via pnpm.overrides.svelte so a single version is resolved everywhere.
• @gradio/utils must match the app's registration contract: Gradio <= 6.8 provides register via a Svelte context (@gradio/utils 0.11.x), Gradio 6.23 provides register_component via shared_props (@gradio/utils 0.14.x). The wrong one silently no-ops registration and the app hangs on its loading screen.

Currently validated against Gradio 6.28.0 (bridge): @gradio/utils@0.14.2, @gradio/client@2.7.0, @gradio/statustracker@^0.15.3, svelte@5.56.9 (the version Gradio 6.28.0 bundles — a newer compiler breaks $$restProps).

Derived from Gradio, licensed under Apache-2.0. See NOTICE.