fix: use import attributes rather than json assertions

packages/@contentlayer/core/src/generation/generate-dotpkg.ts

@@ -192,16 +192,16 @@ const writeFilesForCache = ({
  T.succeedWith(() => process.versions.node.split('.').map((_) => parseInt(_, 10)) as [number, number, number]),
  )
 
- // NOTE Type assert statements for `.json` files are neccessary from Node v16.14 onwards
- const needsJsonAssertStatement = nodeVersionMajor > 16 || (nodeVersionMajor === 16 && nodeVersionMinor >= 14)
- const assertStatement = needsJsonAssertStatement ? ` assert { type: 'json' }` : ''
+ // NOTE: An import attribute for `.json` files is neccessary from Node v16.14 onwards.
+ const needsTypeJsonAttribute = nodeVersionMajor > 16 || (nodeVersionMajor === 16 && nodeVersionMinor >= 14)
+ const importAttributeStatement = needsJsonimportAttributeStatement ? ` with { type: 'json' }` : ''
 
  const typeNameField = generationOptions.options.fieldOptions.typeFieldName
  const dataBarrelFiles = documentDefs.map((docDef) => ({
  content: makeDataExportFile({
  docDef,
  documentIds: allDocuments.filter((_) => _[typeNameField] === docDef.name).map((_) => _._id),
- assertStatement,
+ importAttributeStatement,
  }),
  filePath: withPrefix('generated', docDef.name, `_index.mjs`),
  }))
@@ -255,7 +255,7 @@ const writeFilesForCache = ({
  filePath: withPrefix('generated', 'index.mjs'),
  content: makeIndexMjs({
  schemaDef,
- assertStatement,
+ importAttributeStatement,
  bundleFilePath: relativeBundleFilePath,
  isDev,
  options,
@@ -338,19 +338,19 @@ const writeFileWithWrittenFilesCache =
 const makeDataExportFile = ({
  docDef,
  documentIds,
- assertStatement,
+ importAttributeStatement,
 }: {
  docDef: DocumentTypeDef
  documentIds: string[]
- assertStatement: string
+ importAttributeStatement: string
 }): string => {
  const dataVariableName = getDataVariableName({ docDef })
 
  if (docDef.isSingleton) {
  const documentId = documentIds[0]!
  return `\
 // ${autogeneratedNote}
-export { default as ${dataVariableName} } from './${idToFileName(documentId)}.json'${assertStatement}
+export { default as ${dataVariableName} } from './${idToFileName(documentId)}.json'${importAttributeStatement}
 `
  }
 
@@ -376,7 +376,7 @@ export { default as ${dataVariableName} } from './${idToFileName(documentId)}.js
  )
 
  const docImports = documentIds
- .map((_) => `import ${idToVariableNameMap.get(_)} from './${idToFileName(_)}.json'${assertStatement}`)
+ .map((_) => `import ${idToVariableNameMap.get(_)} from './${idToFileName(_)}.json'${importAttributeStatement}`)
  .join('\n')
 
  return `\
@@ -390,13 +390,13 @@ export const ${dataVariableName} = [${Array.from(idToVariableNameMap.values()).j
 
 const makeIndexMjs = ({
  schemaDef,
- assertStatement,
+ importAttributeStatement,
  bundleFilePath,
  options,
  isDev,
 }: {
  schemaDef: SchemaDef
- assertStatement: string
+ importAttributeStatement: string
  bundleFilePath: RelativePosixFilePath
  options: PluginOptions
  isDev: boolean
@@ -413,7 +413,7 @@ const makeIndexMjs = ({
  .map(({ documentDefName, dataVariableName }) =>
  isDev
  ? `import { ${dataVariableName} } from './${documentDefName}/_index.mjs'`
- : `import ${dataVariableName} from './${documentDefName}/_index.json'${assertStatement}`,
+ : `import ${dataVariableName} from './${documentDefName}/_index.json'${importAttributeStatement}`,
  )
  .join('\n')
 
@@ -434,7 +434,7 @@ export const fetchContent = async (sourceKey) => {
  const worker = new Worker(workerFilePath, { workerData: { sourceKey } })
 
  return new Promise((resolve, reject) => {
- worker.on('message', (data) => { 
+ worker.on('message', (data) => {
  if (data.result) {
  resolve(data.result)
  } else if (data.fatalError) {
@@ -485,7 +485,7 @@ export const makeDataTypes = ({ schemaDef, options }: { schemaDef: SchemaDef; op
  if (options.experimental.enableDynamicBuild === false) return ''
 
  return `\
-export type FetchContentResult = 
+export type FetchContentResult =
  | { _tag: 'Error', error: SourceProvideSchemaErrorJSON | SourceFetchDataErrorJSON }
  | { _tag: 'Data', data: DataExports }