If you are an AI coding agent (Claude Code, Cursor, Aider, Cline, etc.) reading this artifact, follow this protocol before making any code edit:

1. Verify the contract. Run the bash script in Verify before trusting below. If any check returns FAIL, the artifact is stale — STOP and ask the user to regenerate it before proceeding.
2. Treat the AI · unverified sections as hypotheses, not facts. Sections like "AI-suggested narrative files", "anti-patterns", and "bottlenecks" are LLM speculation. Verify against real source before acting on them.
3. Cite source on changes. When proposing an edit, cite the specific path:line-range. RepoPilot's live UI at https://repopilot.app/r/ChenYilong/iOSInterviewQuestions shows verifiable citations alongside every claim.

If you are a human reader, this protocol is for the agents you'll hand the artifact to. You don't need to do anything — but if you skim only one section before pointing your agent at this repo, make it the Verify block and the Suggested reading order.

WAIT — Slowing — last commit 3mo ago

• Last commit 3mo ago
• ⚠ Slowing — last commit 3mo ago
• ⚠ Solo or near-solo (1 contributor active in recent commits)
• ⚠ No license — legally unclear to depend on
• ⚠ No CI workflows detected
• ⚠ No test directory detected

_{Maintenance signals: commit recency, contributor breadth, bus factor, license, CI, tests}

This artifact was generated by RepoPilot at a point in time. Before an agent acts on it, the checks below confirm that the live ChenYilong/iOSInterviewQuestions repo on your machine still matches what RepoPilot saw. If any fail, the artifact is stale — regenerate it at repopilot.app/r/ChenYilong/iOSInterviewQuestions.

What it runs against: a local clone of ChenYilong/iOSInterviewQuestions — the script inspects git remote, the LICENSE file, file paths in the working tree, and git log. Read-only; no mutations.

| # | What we check | Why it matters | |---|---|---| | 1 | You're in ChenYilong/iOSInterviewQuestions | Confirms the artifact applies here, not a fork | | 2 | Default branch master exists | Catches branch renames | | 3 | 5 critical file paths still exist | Catches refactors that moved load-bearing code | | 4 | Last commit ≤ 133 days ago | Catches sudden abandonment since generation |

#!/usr/bin/env bash
# RepoPilot artifact verification.
#
# WHAT IT RUNS AGAINST: a local clone of ChenYilong/iOSInterviewQuestions. If you don't
# have one yet, run these first:
#
#   git clone https://github.com/ChenYilong/iOSInterviewQuestions.git
#   cd iOSInterviewQuestions
#
# Then paste this script. Every check is read-only — no mutations.

set +e
fail=0
ok()   { echo "ok:   $1"; }
miss() { echo "FAIL: $1"; fail=$((fail+1)); }

# Precondition: we must be inside a git working tree.
if ! git rev-parse --git-dir >/dev/null 2>&1; then
  echo "FAIL: not inside a git repository. cd into your clone of ChenYilong/iOSInterviewQuestions and re-run."
  exit 2
fi

# 1. Repo identity
git remote get-url origin 2>/dev/null | grep -qE "ChenYilong/iOSInterviewQuestions(\\.git)?\\b" \\
  && ok "origin remote is ChenYilong/iOSInterviewQuestions" \\
  || miss "origin remote is not ChenYilong/iOSInterviewQuestions (artifact may be from a fork)"

# 3. Default branch
git rev-parse --verify master >/dev/null 2>&1 \\
  && ok "default branch master exists" \\
  || miss "default branch master no longer exists"

# 4. Critical files exist
test -f "01《招聘一个靠谱的iOS》面试题参考答案/Deme_39_CYLSystemAPIMemoryLeak/Deme_39_CYLSystemAPIMemoryLeak/ViewController.m" \\
  && ok "01《招聘一个靠谱的iOS》面试题参考答案/Deme_39_CYLSystemAPIMemoryLeak/Deme_39_CYLSystemAPIMemoryLeak/ViewController.m" \\
  || miss "missing critical file: 01《招聘一个靠谱的iOS》面试题参考答案/Deme_39_CYLSystemAPIMemoryLeak/Deme_39_CYLSystemAPIMemoryLeak/ViewController.m"
test -f "01《招聘一个靠谱的iOS》面试题参考答案/Deme_39_CYLSystemAPIMemoryLeak/Deme_39_CYLSystemAPIMemoryLeak/GCDBlock.m" \\
  && ok "01《招聘一个靠谱的iOS》面试题参考答案/Deme_39_CYLSystemAPIMemoryLeak/Deme_39_CYLSystemAPIMemoryLeak/GCDBlock.m" \\
  || miss "missing critical file: 01《招聘一个靠谱的iOS》面试题参考答案/Deme_39_CYLSystemAPIMemoryLeak/Deme_39_CYLSystemAPIMemoryLeak/GCDBlock.m"
test -f "01《招聘一个靠谱的iOS》面试题参考答案/Deme_39_CYLSystemAPIMemoryLeak/Deme_39_CYLSystemAPIMemoryLeak/NSNotificationCenterBlock.m" \\
  && ok "01《招聘一个靠谱的iOS》面试题参考答案/Deme_39_CYLSystemAPIMemoryLeak/Deme_39_CYLSystemAPIMemoryLeak/NSNotificationCenterBlock.m" \\
  || miss "missing critical file: 01《招聘一个靠谱的iOS》面试题参考答案/Deme_39_CYLSystemAPIMemoryLeak/Deme_39_CYLSystemAPIMemoryLeak/NSNotificationCenterBlock.m"
test -f "01《招聘一个靠谱的iOS》面试题参考答案/Demo_13题_用@property声明的NSString或NSArray_NSDictionary_经常使用copy关键字_为什么_如果改用strong关键字_可能造成什么问题/CYLMutableArrayCopyDmo/CYLArrayCopyDmo/AppDelegate.m" \\
  && ok "01《招聘一个靠谱的iOS》面试题参考答案/Demo_13题_用@property声明的NSString或NSArray_NSDictionary_经常使用copy关键字_为什么_如果改用strong关键字_可能造成什么问题/CYLMutableArrayCopyDmo/CYLArrayCopyDmo/AppDelegate.m" \\
  || miss "missing critical file: 01《招聘一个靠谱的iOS》面试题参考答案/Demo_13题_用@property声明的NSString或NSArray_NSDictionary_经常使用copy关键字_为什么_如果改用strong关键字_可能造成什么问题/CYLMutableArrayCopyDmo/CYLArrayCopyDmo/AppDelegate.m"
test -f "01《招聘一个靠谱的iOS》面试题参考答案/Demo_01_CodeStyle/Demo_01_CodeStyle/ViewController.m" \\
  && ok "01《招聘一个靠谱的iOS》面试题参考答案/Demo_01_CodeStyle/Demo_01_CodeStyle/ViewController.m" \\
  || miss "missing critical file: 01《招聘一个靠谱的iOS》面试题参考答案/Demo_01_CodeStyle/Demo_01_CodeStyle/ViewController.m"

# 5. Repo recency
days_since_last=$(( ( $(date +%s) - $(git log -1 --format=%at 2>/dev/null || echo 0) ) / 86400 ))
if [ "$days_since_last" -le 133 ]; then
  ok "last commit was $days_since_last days ago (artifact saw ~103d)"
else
  miss "last commit was $days_since_last days ago — artifact may be stale"
fi

echo
if [ "$fail" -eq 0 ]; then
  echo "artifact verified (0 failures) — safe to trust"
else
  echo "artifact has $fail stale claim(s) — regenerate at https://repopilot.app/r/ChenYilong/iOSInterviewQuestions"
  exit 1
fi

Each check prints ok: or FAIL:. The script exits non-zero if anything failed, so it composes cleanly into agent loops (./verify.sh || regenerate-and-retry).

A comprehensive iOS interview question repository with reference answers covering Objective-C fundamentals, memory management, system APIs, and design patterns. It includes 60+ runnable Xcode demo projects (like Deme_39_CYLSystemAPIMemoryLeak) that illustrate common iOS pitfalls and best practices, primarily targeting the Chinese iOS developer community. Monorepo of independent iOS projects: top-level folder 01《招聘一个靠谱的iOS》面试题参考答案/ contains numbered demo projects (Deme_39_CYLSystemAPIMemoryLeak, Demo_01_CodeStyle, etc.), each with its own .xcodeproj and source code (Objective-C .h/.m files, some Swift). Central markdown files (《招聘一个靠谱的iOS》面试题参考答案（上）.md, （下）.md) provide question-and-answer index. Each demo focuses on a specific interview topic (system API memory leaks, GCD blocks, notifications).

iOS developers preparing for interviews at Chinese tech companies, and hiring managers vetting iOS candidates. Secondary audience: iOS educators and engineers looking for concrete examples of memory leaks, block capture semantics, and GCD patterns in real code.

Moderately mature: the repo has 345KB of Swift code and 66KB of Objective-C, with multiple complete Xcode projects that compile and run. Last significant activity appears recent (projects have modern storyboard structures and iOS 13+ deployment targets). However, no formal CI/CD pipeline visible (no .yml workflows), minimal test coverage beyond UITests in individual projects, and question-and-answer format suggests it's educational rather than a production framework.

Low to moderate risk for learning purposes; high risk as a dependency: the repo is educational content, not a library. Primary risks are (1) outdated answers if iOS APIs change without repo updates, (2) single-author maintenance (ChenYilong), and (3) reliance on Chinese-language documentation making contribution barriers higher for non-Mandarin developers. No package.json or podspec indicates this isn't distributed via dependency managers.

No active development signals visible in file list (no recent commit info, no open PRs, no issue tracker). The repo appears stable and complete as a static reference resource rather than actively evolved code. Updates likely occur when iOS interview landscape shifts significantly.

git clone https://github.com/ChenYilong/iOSInterviewQuestions.git
cd iOSInterviewQuestions
cd '01《招聘一个靠谱的iOS》面试题参考答案/Deme_39_CYLSystemAPIMemoryLeak'
open Deme_39_CYLSystemAPIMemoryLeak.xcodeproj

Then select a scheme (e.g., Deme_39_CYLSystemAPIMemoryLeak) in Xcode and press Cmd+R to run on iOS 13+ simulator.

Daily commands: Open any .xcodeproj (e.g., Deme_39_CYLSystemAPIMemoryLeak.xcodeproj) in Xcode 11+, select a target scheme, and press Cmd+R. Alternatively, xcodebuild -project Deme_39_CYLSystemAPIMemoryLeak/Deme_39_CYLSystemAPIMemoryLeak.xcodeproj -scheme Deme_39_CYLSystemAPIMemoryLeak -destination 'platform=iOS Simulator,name=iPhone 14' to build and run headlessly.

• 01《招聘一个靠谱的iOS》面试题参考答案/Deme_39_CYLSystemAPIMemoryLeak/Deme_39_CYLSystemAPIMemoryLeak/ViewController.m — Demonstrates system API memory leak patterns with real-world examples of GCD, NSNotificationCenter, NSOperationQueue, and UIView animations that are central to the repo's teaching mission
• 01《招聘一个靠谱的iOS》面试题参考答案/Deme_39_CYLSystemAPIMemoryLeak/Deme_39_CYLSystemAPIMemoryLeak/GCDBlock.m — Core example showing how GCD blocks can cause retain cycles, a fundamental iOS memory management interview topic
• 01《招聘一个靠谱的iOS》面试题参考答案/Deme_39_CYLSystemAPIMemoryLeak/Deme_39_CYLSystemAPIMemoryLeak/NSNotificationCenterBlock.m — Illustrates notification center memory leak patterns, critical for understanding observer pattern pitfalls in iOS
• 01《招聘一个靠谱的iOS》面试题参考答案/Demo_13题_用@property声明的NSString或NSArray_NSDictionary_经常使用copy关键字_为什么_如果改用strong关键字_可能造成什么问题/CYLMutableArrayCopyDmo/CYLArrayCopyDmo/AppDelegate.m — Demonstrates copy vs strong keyword semantics for collections, a core iOS property declaration interview question
• 01《招聘一个靠谱的iOS》面试题参考答案/Demo_01_CodeStyle/Demo_01_CodeStyle/ViewController.m — Entry point for code style and best practices interview content, establishing patterns followed throughout demos
• README.md — Root documentation explaining the repository's purpose, structure, and how to navigate iOS interview question examples

Add a New Memory Leak Pattern Demo

1. Create a new .h/.m file pair in the Deme_39_CYLSystemAPIMemoryLeak directory following the naming convention YourAPINameBlock.h/m (01《招聘一个靠谱的iOS》面试题参考答案/Deme_39_CYLSystemAPIMemoryLeak/Deme_39_CYLSystemAPIMemoryLeak/)
2. Define an interface with a weak reference pattern to demonstrate the memory leak and fix, following the pattern in GCDBlock.h (01《招聘一个靠谱的iOS》面试题参考答案/Deme_39_CYLSystemAPIMemoryLeak/Deme_39_CYLSystemAPIMemoryLeak/GCDBlock.h)
3. Implement both broken (with leak) and fixed (weak reference) versions in the .m file, mirroring NSNotificationCenterBlock.m structure (01《招聘一个靠谱的iOS》面试题参考答案/Deme_39_CYLSystemAPIMemoryLeak/Deme_39_CYLSystemAPIMemoryLeak/NSNotificationCenterBlock.m)
4. Add a method in ViewController.m to instantiate and display your new pattern demo (01《招聘一个靠谱的iOS》面试题参考答案/Deme_39_CYLSystemAPIMemoryLeak/Deme_39_CYLSystemAPIMemoryLeak/ViewController.m)
5. Add your new class to the Xcode project.pbxproj file to include it in the build (01《招聘一个靠谱的iOS》面试题参考答案/Deme_39_CYLSystemAPIMemoryLeak/Deme_39_CYLSystemAPIMemoryLeak.xcodeproj/project.pbxproj)

Add a New Interview Question Demo Project

1. Create a new Xcode project directory following the naming pattern Demo_##题_YourQuestionTopic (01《招聘一个靠谱的iOS》面试题参考答案/)
2. Copy the project structure from Demo_01_CodeStyle or Demo_13题_* as a template, including .xcodeproj configuration (01《招聘一个靠谱的iOS》面试题参考答案/Demo_01_CodeStyle/Demo_01_CodeStyle.xcodeproj/project.pbxproj)
3. Implement ViewController.m with both problem and solution code, following the pattern from existing demos (01《招聘一个靠谱的iOS》面试题参考答案/Demo_01_CodeStyle/Demo_01_CodeStyle/ViewController.m)
4. Add supporting AppDelegate.m and configuration files (Info.plist, Main.storyboard) (01《招聘一个靠谱的iOS》面试题参考答案/Demo_01_CodeStyle/Demo_01_CodeStyle/AppDelegate.m)

Document a New Interview Answer Pattern

1. Create a markdown file in the root or subdirectories with the interview question number and topic (README.md)
2. Create a corresponding Xcode demo project to illustrate the answer with runnable code (01《招聘一个靠谱的iOS》面试题参考答案/Demo_01_CodeStyle/)
3. Include both incorrect and correct implementations as separate methods or files in the demo project (01《招聘一个靠谱的iOS》面试题参考答案/Deme_39_CYLSystemAPIMemoryLeak/Deme_39_CYLSystemAPIMemoryLeak/GCDBlock.m)
4. Update the README.md with a link and brief explanation pointing to your new demo project (README.md)

1. Chinese-only navigation: Folder and file names are entirely in simplified Chinese (《招聘...》), making shell navigation and file searching challenging for non-Mandarin speakers—no English aliases provided. 2. No build configuration in README: Minimum iOS version (inferred from Info.plist as iOS 13+) is not explicitly stated; deploying to older iOS requires manual Xcode adjustments. 3. Xcode workspace quirks: Some projects reference shared data in .xcworkspace/xcshareddata/IDEWorkspaceChecks.plist; opening .xcodeproj directly may cause build warnings. 4. No package management: Projects hardcode dependencies (e.g., no CocoaPods or SPM manifests), making it difficult to add external libraries or replicate builds across machines. 5. Markdown encoding: README and answer files may use BOM or specific UTF-8 encoding; naive text processing tools may corrupt Chinese characters.

• Automatic Reference Counting (ARC) & Retain Cycles — This repo's Demo_39 and block examples (GCDBlock, NSNotificationCenterBlock) directly demonstrate retain cycle bugs where blocks capture self strongly; understanding ARC is mandatory for using any iOS async API without leaking.
• Block Semantics & Capture by Value vs. Reference — Core topic across multiple demo files; blocks in Objective-C capture variables from enclosing scope, and self is captured by reference by default, leading to the retain cycle pitfalls shown in NSNotificationCenterIVARBlock.m and GCDBlock.m.
• Weak Self Pattern & __weak Qualifier — The canonical solution to block retain cycles; repo examples show correct usage of __weak typeof(self) weakSelf pattern in GCDBlock.m and UIViewAnimationsBlock.m to break cycles while maintaining reachability.
• Grand Central Dispatch (GCD) & Dispatch Queues — GCDBlock.m demonstrates dispatch_async, dispatch_after, and other GCD APIs that accept blocks; understanding queue semantics and block retention is essential for concurrent iOS code.
• NSNotificationCenter Subscription Lifecycle — NSNotificationCenterBlock.m and NSNotificationCenterIVARBlock.m illustrate how NSNotificationCenter retains observer blocks; pre-iOS 9, manual unsubscription was required, making this a classic interview topic.
• UIView Animation Block Retention — UIViewAnimationsBlock.m shows that UIView.animate(withDuration:animations:) and related APIs retain completion blocks during animation; failure to manage self in these blocks causes leaks.

• lzyy/iOSGuards — Similar educational iOS interview Q&A repo covering different topics (guards, safety patterns); complementary resource for interview prep in Chinese iOS community
• topskilldev/iOS-Swift-Learning-Path — Structured Swift learning resources; aligns with this repo's secondary Swift code (345KB) and beginner-to-advanced progression model
• raywenderlich/ios-interview-questions-and-answers — English-language equivalent providing iOS interview prep; direct alternative for non-Mandarin audiences with similar Q&A format
• ChenYilong/CYLTabBarController — By same author; production iOS framework demonstrating advanced patterns (custom tab bar, state management) that complement interview question examples
• huixinchen/Memory-Leak-in-iOS — Focused deep-dive on memory leak detection and ARC semantics; pairs well with Deme_39_CYLSystemAPIMemoryLeak examples in this repo

To work on one of these in Claude Code or Cursor, paste: Implement the "<title>" PR idea from CLAUDE.md, working through the checklist as the task list.

Add comprehensive unit tests for memory leak demonstration projects

The repo contains multiple memory leak demo projects (Deme_39_CYLSystemAPIMemoryLeak, GCDBlock, NSNotificationCenterBlock, NSOperationQueueBlock, UIViewAnimationsBlock) but the test files (Deme_39_CYLSystemAPIMemoryLeakTests.m, Info.plist) are minimal. Adding detailed unit tests would validate that each demo properly exhibits the memory leak it's designed to demonstrate and that fixes work correctly.

• [ ] Review existing test files in 01《招聘一个靠谱的iOS》面试题参考答案/Deme_39_CYLSystemAPIMemoryLeak/Deme_39_CYLSystemAPIMemoryLeakTests/
• [ ] Add memory profiling tests for GCDBlock.m, NSNotificationCenterBlock.m, NSOperationQueueBlock.m, and UIViewAnimationsBlock.m
• [ ] Create test assertions that verify memory is not released vs. properly released with fixes
• [ ] Document expected memory leak behavior in test comments

Create a master README index mapping demos to interview questions

The repo contains dozens of numbered demo projects (Demo_01_CodeStyle, Deme_39_CYLSystemAPIMemoryLeak, etc.) but there's no clear mapping showing which Xcode project corresponds to which interview question. Contributors and users cannot easily navigate to the relevant code example for a specific topic.

• [ ] Extract demo directory structure from all subdirectories under 01《招聘一个靠谱的iOS》面试题参考答案/
• [ ] Create a structured table/index in README.md linking demo numbers to interview question topics (e.g., 'Demo_01_CodeStyle → Q1: Code Style Guidelines')
• [ ] Add brief descriptions of what each demo teaches
• [ ] Link to specific .m/.h files within each demo that demonstrate the concept

Add GitHub Actions CI workflow to validate Xcode project builds

The repo contains multiple .xcodeproj files but has no CI/CD pipeline to ensure they compile correctly. This leaves contributors unaware if their changes break builds across different demo projects. A GitHub Action would validate that all Xcode projects build successfully on each PR.

• [ ] Create .github/workflows/xcode-build.yml workflow file
• [ ] Add step to list all .xcodeproj directories in 01《招聘一个靠谱的iOS》面试题参考答案/
• [ ] Add xcodebuild commands to compile each Demo (e.g., Demo_01_CodeStyle.xcodeproj, Deme_39_CYLSystemAPIMemoryLeak.xcodeproj)
• [ ] Configure workflow to run on push to main branches and on pull requests
• [ ] Add build status badge to README.md

• Add English translations for demo folder names: Create a mapping file (e.g., FOLDER_NAMES_EN.md) translating Chinese demo folder paths to English equivalents (e.g., 'Deme_39_CYLSystemAPIMemoryLeak' → 'Demo_39_SystemAPIMemoryLeak') and update README with dual naming—lowers barrier for non-Chinese contributors.
• Write unit tests for memory leak examples: Currently no XCTest code visible in the main answer files; add Deme_39_CYLSystemAPIMemoryLeakTests/MemoryLeakDetectionTests.m with @testcase methods verifying that 'leaked' examples trigger retain cycle detectors and 'fixed' examples pass; demonstrates test-driven learning.
• Document minimum iOS version and build requirements: Create a SETUP.md in the root specifying Xcode 11+, iOS 13+, Swift 5.x requirement, and add a shell script (setup.sh) that validates environment and reports missing tools—reduces 'won't build' friction for new learners.

This is an educational iOS interview questions repository with demo projects. The primary security concern is the inclusion of Xcode user-specific files in version control, which is a common misconfiguration issue. The codebase itself demonstrates various iOS programming patterns, some intentionally showing memory leaks and improper API usage for educational purposes. No critical vulnerabilities, hardcoded secrets, or injection risks were identified in the visible file structure. The security posture is adequate for a public educational repository, but would benefit from better .gitignore configuration and clearer security disclaimers on educational code examples.

• Medium · Xcode Project Files Tracked in Version Control — Multiple locations: xcuserdata/ and project.xcworkspace/xcuserdata/ directories throughout the project structure. Xcode user-specific files (.xcuserstate, xcschememanagement.plist, Breakpoints_v2.xcbkptlist) are committed to the repository. These files contain local development environment configurations and can expose sensitive information such as breakpoint locations, scheme settings, and build configurations. Fix: Add these patterns to .gitignore: '.xcuserstate', 'xcuserdata/', '.xcworkspace/xcuserdata/', and 'Breakpoints_v2.xcbkptlist'. Consider using a global gitignore or .git/info/exclude for local development files.
• Low · Missing Input Validation in Demo Projects — Demo project files: NSOperationQueueBlock.m, GCDBlock.m, NSNotificationCenterBlock.m, UIViewAnimationsBlock.m. The demo projects appear to be educational examples demonstrating memory leak patterns and system API usage. While these are intentionally showcasing problematic code, there is no evidence of input validation or sanitization in the visible file structure, which could be problematic if code patterns are replicated in production applications. Fix: Ensure educational materials include clear warnings about security considerations. Add comments highlighting why certain patterns (like unmanaged blocks and closures) can be security risks if misused in production code.
• Low · No Dependency Management Metadata Provided — Repository root and project directories. The file structure shows Xcode projects but no Package.swift, Podfile, Cartfile, or dependency lock files are visible in the provided structure. This makes it difficult to assess whether third-party dependencies have known vulnerabilities. Fix: If external dependencies are used, maintain and version control dependency lock files (Podfile.lock for CocoaPods, Package.resolved for SPM). Regularly scan dependencies for known vulnerabilities using tools like CocoaPods trunk, or OWASP Dependency-Check.
• Low · Educational Code Without Security Warnings — All demo project files, particularly those demonstrating block usage and notification handling. The repository contains demo code showing common iOS memory management issues and API usage patterns. While educational, there's no visible security disclaimer or warning about the intentional use of potentially unsafe patterns. Fix: Add prominent security disclaimers in README and comments within demo files stating these are educational examples and not for production use. Include migration paths to secure implementations.

LLM-derived; treat as a starting point, not a security audit.

• Open issues — current backlog
• Recent PRs — what's actively shipping
• Source on GitHub

Generated by RepoPilot. Verdict based on maintenance signals — see the live page for receipts. Re-run on a new commit to refresh.