feat(prerender): support quoted true / false values and 0 / 1

[natemoo-re]

Changes

• See https://discord.com/channels/830184174198718474/1067550590512676874/1067550590512676874 for context
• Adds export const prerender support for quoted values of "true" | "false" | 'true' | 'false' as well as the literal values 0, 1.
• This is helpful because Astro replaces import.meta.env.MY_VALUE values statically before prerender is scanned for.
• This should unblock users to control prerendering by using an environment variable like

  PRERENDER_ENABLED=true
  

  ---
  export const prerender = import.meta.env.PRERENDER_ENABLED
  ---

Testing

Scan function unit tests have been updated to check "true" | "false" | 'true' | 'false' and 0 | 1. Did not test import.meta.env.MY_VALUE replacement directly, but can if that seems wise.

Docs

This is mostly intended to unblock users that have tried this already, not sure if we want to document this as an explicit feature yet since we might end up with a different pattern for "preview deploys".

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[Princesseuh]

Agree with not documenting this explicitly! LGTM

[edv-ns]

Looks neat 👍

[ematipico]

Let's 🚢 it!

[samducker]

Hi @natemoo-re

When shipping this I'm getting the following error

@website:build:  error   A `prerender` export has been detected, but its value cannot be statically analyzed.
@website:build:   Expected `true` value but got `process.env.PRERENDER_ENABLED`.
@website:build:   Hint:
@website:build:     Mutable values declared at runtime are not supported. Please make sure to use exactly `export const prerender = true`.
@website:build:   File:
@website:build:     /Users/sam/Documents/GitHub/website/repo/apps/marketing-website/src/pages/about.astro
@website:build:   Stacktrace:
@website:build: InvalidPrerenderExport: A `prerender` export has been detected, but its value cannot be statically analyzed.
@website:build: Expected `true` value but got `process.env.PRERENDER_ENABLED`.
@website:build:     at scan (file:///Users/sam/Documents/GitHub/website/repo/node_modules/.pnpm/astro@2.3.0_@types+node@18.15.13_sharp@0.31.3/node_modules/astro/dist/vite-plugin-scanner/scan.js:42:15)
@website:build:     at processTicksAndRejections (node:internal/process/task_queues:96:5)
@website:build:     at async Object.transform (file:///Users/sam/Documents/GitHub/website/repo/node_modules/.pnpm/astro@2.3.0_@types+node@18.15.13_sharp@0.31.3/node_modules/astro/dist/vite-plugin-scanner/index.js:22:27)

And about.astro

export const prerender = import.meta.env.PRERENDER_ENABLED;

Astro version 2.3.0

[natemoo-re]

Thanks for the report @samducker! I just opened #6910 which should fix this.

[samducker]

Thanks @natemoo-re appreciate you, this will help our content editors lives greatly 🚀