Identation: strange behaviour (spaces vs tabs)

[f3l1x]

• bug report? yes
• feature request? no
• version: 2.8.0

Description

• I have a 1 file composer.json
• I use nette/code-checker: 2.8.0

2 spaces

{
  "name": "my/package"
}

Result: [ERROR] composer.json:2 Mixed tabs and spaces indentation

4 spaces

{
    "name": "my/package"
}

Result: [ERROR] composer.json:2 Mixed tabs and spaces indentation

1 tab

{
  "name": "my/package"
}

Result: OK

2 tabs

{
    "name": "my/package"
}

Result: OK

---

Is there a problem with *.json and spaces? I don't see any invalid chars/rows. 😢

Thank you for your help.