Function physicalRows

test/viewport.test.ts:46–47

(text: string, width: number)

  // even for code-heavy text (the boxed AssistantMessage would have, which caused the
  // oscillation + non-stop scroll bug). We replicate StreamingView's height here.
  const physicalRows = (text: string, width: number) =>
    text.split('\n').reduce((n, ln) => n + Math.max(1, Math.ceil(ln.length / Math.max(20, width))), 0);

  const cases = [
    Array.from({ length: 200 }, (_, i) => `line ${i}`).join('\n'),                 // long prose