TSConfig

Print names of files which TypeScript sees as a part of your project and the reason they are part of the compilation.

For example, with this project of just a single index.ts file

sh
example
├── index.ts
├── package.json
└── tsconfig.json

Using a tsconfig.json which has explainFiles set to true:

json
{
  "compilerOptions": {
    "target": "es5",
    "module": "commonjs",
    "explainFiles": true
  }
}

Running TypeScript against this folder would have output like this:

❯ tsc
node_modules/typescript/lib/lib.d.ts
  Default library for target 'es5'
node_modules/typescript/lib/lib.es5.d.ts
  Library referenced via 'es5' from file 'node_modules/typescript/lib/lib.d.ts'
node_modules/typescript/lib/lib.dom.d.ts
  Library referenced via 'dom' from file 'node_modules/typescript/lib/lib.d.ts'
node_modules/typescript/lib/lib.webworker.importscripts.d.ts
  Library referenced via 'webworker.importscripts' from 
    file 'node_modules/typescript/lib/lib.d.ts'
node_modules/typescript/lib/lib.scripthost.d.ts
  Library referenced via 'scripthost' 
    from file 'node_modules/typescript/lib/lib.d.ts'
index.ts
  Matched by include pattern '**/*' in 'tsconfig.json'

The output above show:

• The initial lib.d.ts lookup based on target, and the chain of .d.ts files which are referenced
• The index.ts file located via the default pattern of include

This option is intended for debugging how a file has become a part of your compile.