TypeScript

Diagnostics Commands

Understand and resolve TypeScript compilation errors and performance issues. Learn to read error messages, trace type resolution, and diagnose slow builds.

5 commands

Pro Tips

Use 'tsc --traceResolution' to debug module resolution issues — shows exactly where TypeScript looks for types.

Use 'tsc --generateTrace ./trace' to profile compilation performance and find bottlenecks.

Use 'tsc --listFiles' to see all files included in compilation — helps find unexpected inclusions.

Common Mistakes

Trace and diagnostic flags produce verbose output. Redirect to a file: 'tsc --traceResolution > trace.log 2>&1'.

Slow TypeScript compilation is often caused by deeply nested types or excessive type inference. Simplify complex types.

Commands

List files only

$ tsc --listFilesOnly

List all files that would be compiled without actually compiling.

Explain file inclusion

$ tsc --explainFiles

Show detailed reasons why each file is part of the compilation.

Generate performance trace

$ tsc --generateTrace ./trace

Create performance trace directory for analyzing slow compilation.

Show compilation stats

$ tsc --diagnostics

Display compilation time and memory usage statistics.

Generate CPU profile

$ tsc --generateCpuProfile tsc-profile.cpuprofile

Create CPU profile for deep performance analysis (Chrome DevTools compatible).