This repo replicated the following bug typestack/class-transformer#1446

Steps

  1. pnpm dev
  2. Open devtools console in the browser
  3. Observe
Person { numbers: Set { 1, 2, 3, 4, 5 } }
{ numbers: [ 1, 2, 3, 4, 5 ] }
Person { numbers: [ 1, 2, 3, 4, 5 ] }

when we expected

Person { numbers: Set { 1, 2, 3, 4, 5 } }
{ numbers: [ 1, 2, 3, 4, 5 ] }
Person { numbers: Set { 1, 2, 3, 4, 5 } }

Place of interest: ./src/App.tsx