<script>'s in <svelte:head> are running twice (unless wrapped in {@html}) #1124
Description
Describe the bug
Adding a <script> tag to <svelte:head> causes the script to be run twice. I believe this is down to Sapper generating the SSR code and then later on hydrating the page with the same element. However, wrapping the script in a @html directive only runs the script once (it looks like the hydration isn't duplicating the element).
Logs
N/A
To Reproduce
I have created a small repo (using sapper-template) that reproduces the issue: https://github.com/notscottthompson/sapper-head-script-test
In the <Nav> component I have added the following:
<svelte:head>
<script>console.log('hello from Nav');</script>
<script src='some-script.js'></script>
{@html '<script src="some-other-script.js"></script>'}
</svelte:head>some-script.js logs "hello from some-script.js".
some-other-script.js logs "hello from some-other-script.js".
The following is logged in the browser when loading the test page:
hello from Nav
hello from some-script.js
hello from some-other-script.js
hello from Nav
hello from some-script.js
Expected behavior
I would expect the following to be logged:
hello from Nav
hello from some-script.js
hello from some-other-script.js
Stacktraces
N/A
Information about your Sapper Installation:
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Your browser and the version: Chrome 80.0
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Your operating system: Ubuntu Linux 18.04
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Your hosting environment: Local
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Sapper version: 0.27.10
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Svelte version: 3.20.1
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If it is an exported (npm run export) or dynamic application: dynamic (
npm run dev) -
Whether your application uses Webpack or Rollup: Rollup
Severity
Only mildly annoying. However, due to not being an expert in Svelte/Sapper I'm worried that this may be something I shouldn't be doing (wrapping scripts in @html) or that there may be a better way to achieve it.
Additional context
N/A