test: lock Apple fling fallback route

Author: thymikee

src/__tests__/apple-runner-gesture-contract.test.ts

@@ -0,0 +1,61 @@
+import assert from 'node:assert/strict';
+import fs from 'node:fs';
+import path from 'node:path';
+import { fileURLToPath } from 'node:url';
+import { test } from 'vitest';
+
+const repoRoot = path.resolve(path.dirname(fileURLToPath(import.meta.url)), '../..');
+const commandExecutionSwiftPath = path.join(
+  repoRoot,
+  'apple-runner/AgentDeviceRunner/AgentDeviceRunnerUITests/RunnerTests+CommandExecution.swift',
+);
+
+test('Apple gesture command preserves the fling fast-swipe and coordinate fallback route', () => {
+  const source = fs.readFileSync(commandExecutionSwiftPath, 'utf8');
+  const gestureCase = extractSwiftSwitchCase(source, '.gesture', '.gestureViewport');
+  const fastSwipeBranch = extractSourceSegment(
+    gestureCase,
+    'if plannedGestureExecution(for: plan) == .fastSwipe',
+    'let (timing, outcome)',
+  );
+
+  assert.match(fastSwipeBranch, /executeDragGesture\(/);
+  assert.match(fastSwipeBranch, /synthesized:\s*true/);
+  assert.match(fastSwipeBranch, /synthesizedPolicyKind:\s*\.synthesizedDrag/);
+  assert.match(fastSwipeBranch, /synthesizedProfile:\s*\.fastSwipe/);
+  assert.doesNotMatch(fastSwipeBranch, /sampledPlannedGesture/);
+
+  const dragExecutor = extractSwiftFunction(source, 'executeDragGesture');
+  assert.match(
+    dragExecutor,
+    /fallback = gestureFallback\(strategy: "xctest-coordinate-drag", from: outcome\)/,
+  );
+  assert.match(dragExecutor, /dragAt\(/);
+});
+
+function extractSwiftSwitchCase(source: string, name: string, nextName: string): string {
+  return extractSourceSegment(source, `case ${name}:`, `case ${nextName}:`);
+}
+
+function extractSourceSegment(source: string, startMarker: string, endMarker: string): string {
+  const start = source.indexOf(startMarker);
+  assert.notEqual(start, -1, `missing source marker ${startMarker}`);
+  const end = source.indexOf(endMarker, start);
+  assert.notEqual(end, -1, `missing source marker ${endMarker}`);
+  return source.slice(start, end);
+}
+
+function extractSwiftFunction(source: string, name: string): string {
+  const signatureIndex = source.indexOf(`func ${name}`);
+  assert.notEqual(signatureIndex, -1, `missing Swift function ${name}`);
+  const bodyStart = source.indexOf('{', signatureIndex);
+  assert.notEqual(bodyStart, -1, `missing Swift function body ${name}`);
+  let depth = 0;
+  for (let index = bodyStart; index < source.length; index += 1) {
+    const char = source[index];
+    if (char === '{') depth += 1;
+    if (char === '}') depth -= 1;
+    if (depth === 0) return source.slice(signatureIndex, index + 1);
+  }
+  assert.fail(`unterminated Swift function ${name}`);
+}