How tsconfig exclude pattern should actually work

TypeScript Version: 2.1.1 / nightly (2.2.0-dev.201xxxxx)

Say we have a following structure to specially to test exclude pattern:

/node_modules
  /module/some.ts
nested/
  /node_modules
    /module/some.ts
  /deep-nested/
    /node_modules
      /module/some.ts

Will check this using tsc --listFiles

How exclude patterns work:

1. "node_modules" - will exclude only /node_modules/module/some.ts
2. "*/node_modules" (the same effect as /node_modules/") - will exclude only /nested/node_modules/module/some.ts
3. "**/node_modules" - will exclude nothing
4. "**/node_modules/*" - will exclude everything (also nested, deep-nested)

Some behaviour seem strange to me

• why in case 3 it excludes nothing (considering case 2 works)?
• by default (if exclude not specified) case 1 will be effective, shouldn't it be 4) which excludes node_modules in nested folders as well?

Comienza con el comando tsc --listFiles indicado y reproduce la estructura de directorios listada utilizando los cuatro patrones de exclude. Sigue el procesamiento de los patrones de exclusión del compilador para determinar por qué los patrones seleccionan directorios diferentes; después, añade o actualiza la cobertura para los casos observados y verifica el comportamiento previsto.