build: enable noUncheckedIndexedAccess (#600)

* build: enable noUncheckedIndexedAccess

* refactor: remove redundant indexed access fallbacks

* fix: address rebased unchecked indexed access

* fix: address unchecked access review feedback

* refactor: simplify replay fill positional typing

* refactor: avoid wait positional assertion

* refactor: prefer value guards for indexed access

* chore: keep fallow baseline for strictness changes

Author: thymikee

src/__tests__/cli-batch.test.ts

@@ -37,7 +37,7 @@ test('batch --steps parses JSON and forwards batchSteps only', async () => {
   ]);
   assert.equal(result.code, null);
   assert.equal(result.calls.length, 1);
-  const req = result.calls[0];
+  const req = result.calls[0]!;
   assert.equal(req.command, 'batch');
   assert.equal(req.session, 'sim');
   assert.equal(req.flags?.platform, 'ios');
@@ -57,7 +57,7 @@ test('batch --steps-file parses file payload', async () => {
   const result = await runCliCapture(['batch', '--steps-file', stepsPath, '--json']);
   assert.equal(result.code, null);
   assert.equal(result.calls.length, 1);
-  const req = result.calls[0];
+  const req = result.calls[0]!;
   assert.equal(req.command, 'batch');
   assert.equal((req.flags?.batchSteps ?? [])[0]?.command, 'wait');
 });
@@ -88,7 +88,7 @@ test('batch accepts legacy positionals/flags steps with deprecation warning', as
   assert.equal(result.code, null);
   assert.match(result.stderr, /positionals\/flags are deprecated.*next major version/);
   assert.equal(result.calls.length, 1);
-  const req = result.calls[0];
+  const req = result.calls[0]!;
   assert.equal(req.command, 'batch');
   assert.deepEqual((req.flags?.batchSteps ?? [])[0], {
     command: 'open',

src/__tests__/client-companion-tunnel-worker.test.ts

@@ -121,7 +121,7 @@ function decodeWebSocketPayload(payload: Buffer, mask: Buffer | null): Buffer {
 
   const decoded = Buffer.from(payload);
   for (let index = 0; index < decoded.length; index += 1) {
-    decoded[index] ^= mask[index % 4];
+    decoded[index]! ^= mask[index % 4]!;
   }
   return decoded;
 }

src/__tests__/selectors-public.test.ts

@@ -37,7 +37,7 @@ const nodes: SnapshotNode[] = [
 
 test('public selector subpath exposes platform-aware matching helpers', () => {
   const chain: SelectorChain = parseSelectorChain('role=button label="Continue" visible=true');
-  const firstSelector: Selector = chain.selectors[0];
+  const firstSelector: Selector = chain.selectors[0]!;
   assert.equal(firstSelector.raw, 'role=button label="Continue" visible=true');
   assert.equal(tryParseSelectorChain(chain.raw)?.raw, chain.raw);
   assert.equal(isSelectorToken('visible=true'), true);
@@ -55,8 +55,8 @@ test('public selector subpath exposes platform-aware matching helpers', () => {
   });
   assert.equal(resolved?.node.ref, 'e1');
 
-  assert.equal(isNodeVisible(nodes[0]), true);
-  assert.equal(isNodeEditable(nodes[1], 'android'), true);
+  assert.equal(isNodeVisible(nodes[0]!), true);
+  assert.equal(isNodeEditable(nodes[1]!, 'android'), true);
 });
 
 test('public selector diagnostics format failures', () => {

src/__tests__/upload-client.test.ts

@@ -350,7 +350,7 @@ test('uploadArtifact disables macOS AppleDouble entries when archiving app bundl
       (cmd, args, options) => {
         if (cmd !== 'tar') return undefined;
         tarEnv = options.env;
-        const archivePath = args[1];
+        const archivePath = args[1]!;
         assert.equal(args[0], 'czf');
         assert.equal(typeof archivePath, 'string');
         fs.writeFileSync(archivePath, 'fake-archive');

src/cli.ts

@@ -481,7 +481,7 @@ function hasExplicitMetroRuntimeOverrides(explicitFlagKeys: Set<FlagKey>): boole
 
 function guessSessionFromArgv(argv: string[]): string | null {
   for (let i = 0; i < argv.length; i += 1) {
-    const token = argv[i];
+    const token = argv[i]!;
     if (token.startsWith('--session=')) {
       const inline = token.slice('--session='.length).trim();
       return inline.length > 0 ? inline : null;

src/commands/cli-grammar/capture.ts

@@ -116,15 +116,16 @@ function readWaitOptionsFromPositionals(
 }
 
 export function parseWaitPositionals(args: string[]): WaitParsed | null {
-  if (args.length === 0) return null;
-  const sleepMs = parseTimeout(args[0]);
+  const firstArg = args[0];
+  if (firstArg === undefined) return null;
+  const sleepMs = parseTimeout(firstArg);
   if (sleepMs !== null) return { kind: 'sleep', durationMs: sleepMs };
   const timeoutMs = parseTimeout(args[args.length - 1]);
-  if (args[0] === 'text') {
+  if (firstArg === 'text') {
     const text = timeoutMs !== null ? args.slice(1, -1).join(' ') : args.slice(1).join(' ');
     return { kind: 'text', text: text.trim(), timeoutMs };
   }
-  if (args[0].startsWith('@')) return { kind: 'ref', rawRef: args[0], timeoutMs };
+  if (firstArg.startsWith('@')) return { kind: 'ref', rawRef: firstArg, timeoutMs };
   const argsWithoutTimeout = timeoutMs !== null ? args.slice(0, -1) : args.slice();
   const split = splitSelectorFromArgs(argsWithoutTimeout);
   if (split && split.rest.length === 0 && tryParseSelectorChain(split.selectorExpression)) {

src/commands/cli-grammar/interactions.ts

@@ -140,14 +140,15 @@ function readLongPressTargetFromPositionals(positionals: string[]): LongPressOpt
 }
 
 export function readFillTargetFromPositionals(positionals: string[]): DecodedFillTarget {
-  if (positionals[0]?.startsWith('@')) {
+  const firstPositional = positionals[0];
+  if (firstPositional?.startsWith('@')) {
     const text =
       positionals.length >= 3 ? positionals.slice(2).join(' ') : positionals.slice(1).join(' ');
     return {
       kind: 'ref',
       target: {
-        ref: positionals[0],
-        label: positionals.length >= 3 ? optionalTrimmedText([positionals[1]]) : undefined,
+        ref: firstPositional,
+        label: positionals.length >= 3 ? optionalTrimmedText(positionals.slice(1, 2)) : undefined,
       },
       text,
     };

src/commands/interaction-targeting.ts

@@ -80,7 +80,9 @@ function findPreferredActionableDescendant(
     if (sameRectChildren.length !== 1) {
       break;
     }
-    current = sameRectChildren[0];
+    const child = sameRectChildren[0];
+    if (child === undefined) break;
+    current = child;
   }
 
   return current === node ? null : current;

src/commands/react-native/overlay.ts

@@ -177,15 +177,17 @@ function actionFromDismissNode(node: SnapshotNode): ReactNativeOverlayDismissTar
 function chooseCollapsedWarningNode(nodes: SnapshotNode[]): SnapshotNode | null {
   const withRect = nodes.filter((node) => node.rect);
   if (withRect.length === 0) return null;
-  return withRect.sort((a, b) => {
-    const aHittable = a.hittable === true ? 1 : 0;
-    const bHittable = b.hittable === true ? 1 : 0;
-    if (aHittable !== bHittable) return bHittable - aHittable;
-    const aWidth = a.rect?.width ?? 0;
-    const bWidth = b.rect?.width ?? 0;
-    if (aWidth !== bWidth) return bWidth - aWidth;
-    return (b.rect?.y ?? 0) - (a.rect?.y ?? 0);
-  })[0];
+  return (
+    withRect.sort((a, b) => {
+      const aHittable = a.hittable === true ? 1 : 0;
+      const bHittable = b.hittable === true ? 1 : 0;
+      if (aHittable !== bHittable) return bHittable - aHittable;
+      const aWidth = a.rect?.width ?? 0;
+      const bWidth = b.rect?.width ?? 0;
+      if (aWidth !== bWidth) return bWidth - aWidth;
+      return (b.rect?.y ?? 0) - (a.rect?.y ?? 0);
+    })[0] ?? null
+  );
 }
 
 function collapsedBannerClosePoint(node: SnapshotNode): Point {

src/compat/maestro/replay-flow.ts

@@ -85,7 +85,7 @@ function optimizeInputTextActions(
   const mergedActions: SessionAction[] = [];
   const mergedLines: number[] = [];
   for (let index = 0; index < actions.length; index += 1) {
-    const action = actions[index];
+    const action = actions[index]!;
     const optimized = optimizeTypedAfterTap(actions, actionLines, index);
     if (optimized) {
       mergedActions.push(...optimized.actions);
@@ -104,16 +104,17 @@ function optimizeTypedAfterTap(
   actionLines: number[],
   index: number,
 ): { actions: SessionAction[]; actionLines: number[]; consumed: number } | null {
-  const action = actions[index];
+  const action = actions[index]!;
   const nextAction = actions[index + 1];
   const typedAfterTap = readPlainTypeText(nextAction);
   const tapSelector = readPlainMaestroTapSelector(action);
-  if (typedAfterTap === null || tapSelector === null) return null;
+  if (!nextAction || typedAfterTap === null || tapSelector === null) return null;
   const line = actionLines[index] ?? 1;
   if (!isLikelyTextEntrySelector(tapSelector)) {
     return { actions: [clearMaestroNonHittableTap(action)], actionLines: [line], consumed: 1 };
   }
-  if (actions[index + 2]?.command !== MAESTRO_RUNTIME_COMMAND.pressEnter) {
+  const pressEnterAction = actions[index + 2];
+  if (pressEnterAction?.command !== MAESTRO_RUNTIME_COMMAND.pressEnter) {
     return { actions: [clearMaestroNonHittableTap(action)], actionLines: [line], consumed: 1 };
   }
   return {
@@ -129,7 +130,7 @@ function optimizeTypedAfterTap(
         positionals: [tapSelector, typedAfterTap],
         flags: action.flags,
       },
-      actions[index + 2] as SessionAction,
+      pressEnterAction,
     ],
     actionLines: [line, line, actionLines[index + 2] ?? line],
     consumed: 3,