Cannot read property 'toString' of undefined

[zlk89]

Description

Getting error when running any command:

> npx lint-staged --help -d
Cannot read property 'toString' of undefined

Steps to reproduce

1. Upgrade macOS to Catalina 10.15.6
2. Running any command will trigger this error.

Debug Logs

expand to view

xxx/node_modules/lint-staged/bin/lint-staged.js:8
  process.env.FORCE_COLOR = supportsColor.level.toString()
                                                  ^

TypeError: Cannot read property 'toString' of undefined
    at Object.<anonymous> (xxx/node_modules/lint-staged/bin/lint-staged.js:8:49)

Environment

• OS: macOS Catalina 10.15.6
• Node.js: v12.16.1
• lint-staged: 10.2.11

[iiroj]

Thanks for the issue!

EDIT: on further investigation, if supportsColor is truthy, it should always have a numeric supportsColor.level property.

In any case, I'll open a PR to double-check.