Function processFileBlock

packages/agent-runtime/src/process-file-block.ts:33–125

(
  params: {
    path: string
    initialContentPromise: Promise<string | null>
    newContent: string
    logger: Logger
  },
)

 * - `{ aborted: false, value: WriteFileResult }` on success or recoverable error
 */
export async function processFileBlock(
  params: {
    path: string
    initialContentPromise: Promise<string | null>
    newContent: string
    logger: Logger
  },
): Promise<PromptResult<WriteFileResult>> {
  const {
    path,
    initialContentPromise,
    newContent,
    logger,
  } = params
  const initialContent = await initialContentPromise

  if (initialContent === null) {
    const cleanContent = cleanMarkdownCodeBlock(newContent)

    logger.debug(
      { path, cleanContent },
      `processFileBlock: Created new file ${path}`,
    )
    return promptSuccess({
      tool: 'write_file' as const,
      path,
      content: cleanContent,
      patch: undefined,
      messages: [`Created new file ${path}`],
    })
  }

  if (newContent === initialContent) {
    logger.info(
      { newContent },
      `processFileBlock: New was same as old, skipping ${path}`,
    )
    return promptSuccess({
      tool: 'write_file' as const,
      path,
      error: 'The new content was the same as the old content, skipping.',
    })
  }

  const lineEnding = initialContent.includes('\r\n') ? '\r\n' : '\n'
  const normalizeLineEndings = (str: string) => str.replace(/\r\n/g, '\n')
  const normalizedInitialContent = normalizeLineEndings(initialContent)
  const normalizedNewContent = normalizeLineEndings(newContent)

  let patch = createPatch(path, normalizedInitialContent, normalizedNewContent)
  const lines = patch.split('\n')
  const hunkStartIndex = lines.findIndex((line) => line.startsWith('@@'))
  if (hunkStartIndex !== -1) {
    patch = lines.slice(hunkStartIndex).join('\n')
  } else {
    logger.debug(
      {
        path,