Function extractReadFilesFromMessages

src/utils/queryHelpers.ts:388–551

(
  messages: Message[],
  cwd: string,
  maxSize: number = ASK_READ_FILE_STATE_CACHE_SIZE,
)

// Create a function to extract read files from messages
export function extractReadFilesFromMessages(
  messages: Message[],
  cwd: string,
  maxSize: number = ASK_READ_FILE_STATE_CACHE_SIZE,
): FileStateCache {
  const cache = createFileStateCacheWithSizeLimit(maxSize)

  // First pass: find all FileReadTool/FileWriteTool/FileEditTool uses in assistant messages
  const fileReadToolUseIds = new Map<string, string>() // toolUseId -> filePath
  const fileWriteToolUseIds = new Map<
    string,
    { filePath: string; content: string }
  >() // toolUseId -> { filePath, content }
  const fileEditToolUseIds = new Map<string, string>() // toolUseId -> filePath

  for (const message of messages) {
    if (
      message.type === 'assistant' &&
      Array.isArray(message.message!.content)
    ) {
      for (const content of message.message!.content) {
        if (
          content.type === 'tool_use' &&
          content.name === FILE_READ_TOOL_NAME
        ) {
          // Extract file_path from the tool use input
          const input = content.input as FileReadInput | undefined
          // Ranged reads are not added to the cache.
          if (
            input?.file_path &&
            input?.offset === undefined &&
            input?.limit === undefined
          ) {
            // Normalize to absolute path for consistent cache lookups
            const absolutePath = expandPath(input.file_path, cwd)
            fileReadToolUseIds.set(content.id, absolutePath)
          }
        } else if (
          content.type === 'tool_use' &&
          content.name === FILE_WRITE_TOOL_NAME
        ) {
          // Extract file_path and content from the Write tool use input
          const input = content.input as
            | { file_path?: string; content?: unknown }
            | undefined
          if (
            input?.file_path &&
            input.content !== undefined &&
            input.content !== null
          ) {
            // Normalize to absolute path for consistent cache lookups
            const absolutePath = expandPath(input.file_path, cwd)
            fileWriteToolUseIds.set(content.id, {
              filePath: absolutePath,
              content: coerceToolContentToString(input.content),
            })
          }
        } else if (