Script Kit UI Testing

All UI testing uses the stdin JSON protocol. Never pass scripts as CLI arguments.

Stdin JSON Protocol

Correct:

echo '{"type":"run","path":"'"$(pwd)"'/tests/smoke/test-editor-height.ts"}' | \
  SCRIPT_KIT_AI_LOG=1 ./target/debug/script-kit-gpui 2>&1

Wrong (does nothing):

./target/debug/script-kit-gpui tests/smoke/hello-world.ts

Always set SCRIPT_KIT_AI_LOG=1 when testing (saves ~70% tokens).

Available Stdin Commands

{"type":"run","path":"/abs/path/to/script.ts"}
{"type":"show"}
{"type":"hide"}
{"type":"setFilter","text":"search term"}
{"type":"showGrid","showBounds":true}
{"type":"hideGrid"}
{"type":"openNotes"}
{"type":"openAi"}

Build-Test Loop

cargo build
echo '{"type":"run","path":"'"$(pwd)"'/tests/smoke/test-editor-height.ts"}' | \
  SCRIPT_KIT_AI_LOG=1 ./target/debug/script-kit-gpui 2>&1

Log filtering:

... | grep -iE 'RESIZE|editor|height_for_view|700'
tail -50 ~/.scriptkit/logs/script-kit-gpui.jsonl | grep -i resize

Visual Testing (Screenshots)

Use SDK captureScreenshot() (captures only the app window). Save PNG to .test-screenshots/. Read the PNG to verify.

Blocked tools (do not use): screencapture, scrot, gnome-screenshot, flameshot, maim, ImageMagick import.

Minimal pattern:

import '../../scripts/kit-sdk';
import { mkdirSync, writeFileSync } from 'fs';
import { join } from 'path';

await div(`<div class="p-4 bg-blue-500 text-white rounded-lg">Test</div>`);
await new Promise(r => setTimeout(r, 500));

const shot = await captureScreenshot();
const dir = join(process.cwd(), '.test-screenshots');
mkdirSync(dir, { recursive: true });

const path = join(dir, `shot-${Date.now()}.png`);
writeFileSync(path, Buffer.from(shot.data, 'base64'));
console.error(`[SCREENSHOT] ${path}`);
process.exit(0);

Grid Overlay

echo '{"type":"showGrid","showBounds":true}' | ./target/debug/script-kit-gpui
echo '{"type":"showGrid","showBounds":true,"showBoxModel":true,"showAlignmentGuides":true,"showDimensions":true}' | ./target/debug/script-kit-gpui
echo '{"type":"hideGrid"}' | ./target/debug/script-kit-gpui

Options: gridSize (default 8), showBounds, showBoxModel, showAlignmentGuides, showDimensions, depth ("prompts" | "all" | component names).

Color coding: prompts red, inputs teal, buttons yellow, lists mint, headers plum, containers sky.

Programmatic Layout Info

SDK getLayoutInfo() returns:

interface LayoutInfo {
  windowWidth: number; windowHeight: number;
  promptType: string; // "arg"|"div"|"editor"|"mainMenu"|...
  components: LayoutComponentInfo[];
  timestamp: string;
}

Anti-Patterns

• Running scripts via CLI args (must use stdin JSON)
• "I can't test without manual interaction" (use stdin + logs + screenshots)
• Not using SCRIPT_KIT_AI_LOG=1
• Capturing screenshot but not reading/verifying PNG
• Guessing at layout (use captureScreenshot() / getLayoutInfo() / grid overlay)

References

• Layout Info Details - Full LayoutComponentInfo interface