Bug repro

1. import from "$env" is not available in instrumentation.server.js

When importing from $env in instrumentation.server.js, the import is not available in certain scenario's.

1. vite dev

Output:

dev true
process.env undefined
$env/dynamic/public InstrumentationKey=00000000-0000-0000-0000-000000000000;IngestionEndpoint=https://applicationinsights.azure.com/;LiveEndpoint=https://livediagnostics.monitor.azure.com/;ApplicationId= 00000000-0000-0000-0000-000000000000

2. vite preview Output:

<<<EOF

3. node --env-file=.env ./build

dev false
process.env InstrumentationKey=00000000-0000-0000-0000-000000000000;IngestionEndpoint=https://applicationinsights.azure.com/;LiveEndpoint=https://livediagnostics.monitor.azure.com/;ApplicationId= 00000000-0000-0000-0000-000000000000
$env/dynamic/public undefined

2. Instrumentation is not loaded in vite preview

When running vite preview, the instrumentation is not loaded, even though it is available in the build output.

The log statements in instrumentation.server.js are not shown.

<<<EOF

3. Build fails without an error message

When an instrumentation.server.js file is present but instrumentation is not enabled in svelte.config.js, the build fails without any error message.

This took me a second to figure out what went wrong when setting up this repository. this happens when experimental.instrumentation is disabled or this property is just not present.

experimental: {
    instrumentation: {
        server: false,
    },
},

This is the full output, no actual message is shown:

$ npm run build

> [email protected] build
> vite build

error during build:

<<<EOF