fix(plugin-vue): hmr not working when updating script+template at the same time with a template preprocessor

[rashfael]

Description

Fixes #28 and #76.

When using pug as a template preprocessor and if you update both script and template at the same time, you will get

Property "foo" was accessed during render but is not defined on instance.

as a browser console error instead of hmr updating properly.
This is because the template compilation relies on the compiled script being already in cache, which in this case it isn't, because the hmr requests both template and script modules at the same time (see #28 for timing).

This fix makes sure that the script cache is always populated before the template is compiled.

Additional context

I'm not sure if calling resolveScript on every template compile is overkill, but resolveScript has an early return if there is already cached result. I could not get the relevant context ("template+script update at same time") on compile time, since this information is lost when the hmr client makes two separate requests.

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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[zaxlct]

I also encountered the same problem. Why hasn't this PR been merged yet.

[patak-dev]

This looks good to me

[haoqunjiang]

Thanks! It's a pleasure to review PRs with such detailed explanations.