No server-sent event if servedir is undefined

[yzrmn]

Hi :)

I had some weird behavior with the new context() API when using watch() and serve() and without defining servedir.
Although this happened by mistake it still caused quite the confusion.

Consider:

export async function serveHelper(
    buildOptions: BuildOptions,
    serveOptions: ServeOptions,
    watchOptions?: WatchOptions
): Promise<void> {
    const contextOptions = { ...buildOptions };

    if (watchOptions !== undefined) {
        if (contextOptions.format === "iife") {
            contextOptions.footer = { js: FOOTER_LIVE_RELOAD_IIFE };
        } else {
            contextOptions.footer = { js: FOOTER_LIVE_RELOAD_DEFAULT };
        }
    }

    const ctx = await context(contextOptions);

    if (watchOptions !== undefined) {
        ctx.watch(watchOptions);
    }

    await ctx.serve(serveOptions);
}

serveHelper(
    {
        bundle: true,
        entryPoints: ["./src/index.ts", "./src/index.html"],
        format: "esm",
        loader: { ".html": "copy" },
        outdir: "./dist",
    },
    {
        host: "127.0.0.1",
        port: 8001,
    },
    {}
);

It seems to do the right thing and serves the files. It also correctly watches the files and rebuilds them. However, it does not send the server event to trigger a live reload when using:

new EventSource('/esbuild').addEventListener('change', () => location.reload())

If servedir is set to ./dist everything works as expected and the server event is sent.

[evanw]

Thanks very much for the report. Looks like I'm missing test coverage for this. I'll fix this in the next release.