test: add reproducible FreeCAD golden oracle

scripts/fetch-freecad-source.mjs

@@ -0,0 +1,27 @@
+import { execFileSync } from 'node:child_process'
+import { mkdir, stat } from 'node:fs/promises'
+import { dirname, resolve } from 'node:path'
+import { readFile } from 'node:fs/promises'
+
+const root = resolve(new URL('..', import.meta.url).pathname)
+const toolchain = JSON.parse(await readFile(new URL('../config/freecad-toolchain.json', import.meta.url), 'utf8'))
+const directoryArgument = process.argv.slice(2).find((argument) => argument.startsWith('--directory='))
+const target = resolve(root, directoryArgument?.slice('--directory='.length) || toolchain.sourceCheckout.defaultDirectory)
+const git = (...args) => execFileSync('git', args, { cwd: root, encoding: 'utf8', stdio: ['ignore', 'pipe', 'inherit'], timeout: 300000 }).trim()
+const exists = await stat(target).then(() => true, () => false)
+
+if (!exists) {
+  await mkdir(dirname(target), { recursive: true })
+  git('clone', '--filter=blob:none', '--no-checkout', toolchain.source.repository, target)
+} else {
+  const remote = git('-C', target, 'remote', 'get-url', 'origin')
+  if (remote !== toolchain.source.repository) throw new Error(`Existing checkout has unexpected origin: ${remote}`)
+  const dirty = git('-C', target, 'status', '--porcelain')
+  if (dirty) throw new Error(`Existing FreeCAD checkout is dirty: ${target}`)
+}
+
+git('-C', target, 'fetch', '--depth=1', 'origin', `refs/tags/${toolchain.source.tag}`)
+const fetched = git('-C', target, 'rev-parse', 'FETCH_HEAD')
+if (fetched !== toolchain.source.commit) throw new Error(`Fetched FreeCAD tag resolved to ${fetched}, expected ${toolchain.source.commit}.`)
+git('-C', target, 'checkout', '--detach', toolchain.source.commit)
+console.log(`FreeCAD source ready: ${target} @ ${toolchain.source.commit}`)