This file is the canonical resource for compatibility goals for the libraries that make up Sinon.JS.
Sinon has historically been written as ES5, but starting from Sinon 10 we made the breaking change to allow more modern ECMAScript versions, starting with ECMAScript 2017. The source version is ES2017 and requires no transpiler or polyfills in supporting runtimes.
For legacy runtimes, a transpiler can be used by dependent projects., but use of newer APIs might break. If you need to support older browsers, have a look at Sinon 9.
Sinon.JS aims at supporting the following runtimes (from our shared eslint-config).
> 0.5%
last 2 versions
Firefox ESR
not dead
not IE 11
not op_mini all
maintained node versions
The compatibility is enforced using eslint-plugin-compat.
To see what that means in practice, you can use https://browserslist.dev
