Function translateTree

lib/page-data.js:69–181

(dir, langObj, enTree)

}

async function translateTree(dir, langObj, enTree) {
  const item = {}
  const enPage = enTree.page
  const { ...enData } = enPage

  const basePath = dir
  const relativePath = enPage.relativePath
  const fullPath = path.join(basePath, relativePath)

  let data
  let content
  try {
    const read = await readFileContents(fullPath)
    // If it worked, great!
    content = read.content
    data = read.data

    if (!data) {
      // If the file's frontmatter Yaml is entirely broken,
      // the result of `readFileContents()` is that you just
      // get a `errors` key. E.g.
      //
      //   errors: [
      //     {
      //       reason: 'invalid frontmatter entry',
      //       message: 'YML parsing error!',
      //       filepath: 'translations/ja-JP/content/get-started/index.md'
      //     }
      //   ]
      //
      // If this the case throw error so we can lump this error with
      // how we deal with the file not even being present on disk.
      throw new FrontmatterParsingError(read.errors)
    }

    for (const { property } of read.errors) {
      // If any of the errors happened on keys that are considered
      // translatable, we can't accept that and have to fall back to
      // English.
      // For example, if a Japanese page's frontmatter lacks `title`,
      // (which triggers a 'is required' error) you can't include it
      // because you'd have a Page with `{title: undefined}`.
      // The beauty in this is that if the translated content file
      // has something wrong with, say, the `versions` frontmatter key
      // we don't even care because we won't be using it anyway.
      if (translatableFrontmatterKeys.includes(property)) {
        const message = `frontmatter error on '${property}' (in ${fullPath}) so falling back to English`
        if (DEBUG_TRANSLATION_FALLBACKS) {
          // The object format is so the health report knows which path the issue is on
          console.warn({ message, path: relativePath })
        }
        if (THROW_TRANSLATION_ERRORS) {
          throw new Error(message)
        }
        data[property] = enData[property]
      }
    }
  } catch (error) {