Function writeDiffToTerminal

src/ink/terminal.ts:190–248

(
  terminal: Terminal,
  diff: Diff,
  skipSyncMarkers = false,
)

}

export function writeDiffToTerminal(
  terminal: Terminal,
  diff: Diff,
  skipSyncMarkers = false,
): void {
  // No output if there are no patches
  if (diff.length === 0) {
    return
  }

  // BSU/ESU wrapping is opt-out to keep main-screen behavior unchanged.
  // Callers pass skipSyncMarkers=true when the terminal doesn't support
  // DEC 2026 (e.g. tmux) AND the cost matters (high-frequency alt-screen).
  const useSync = !skipSyncMarkers

  // Buffer all writes into a single string to avoid multiple write calls
  let buffer = useSync ? BSU : ''

  for (const patch of diff) {
    switch (patch.type) {
      case 'stdout':
        buffer += patch.content
        break
      case 'clear':
        if (patch.count > 0) {
          buffer += eraseLines(patch.count)
        }
        break
      case 'clearTerminal':
        buffer += getClearTerminalSequence()
        break
      case 'cursorHide':
        buffer += HIDE_CURSOR
        break
      case 'cursorShow':
        buffer += SHOW_CURSOR
        break
      case 'cursorMove':
        buffer += cursorMove(patch.x, patch.y)
        break
      case 'cursorTo':
        buffer += cursorTo(patch.col)
        break
      case 'carriageReturn':
        buffer += '\r'
        break
      case 'hyperlink':
        buffer += link(patch.uri)
        break
      case 'styleStr':
        buffer += patch.str
        break
    }
  }

  // Add synchronized update end and flush buffer
  if (useSync) buffer += ESU
  terminal.stdout.write(buffer)