PR Summary

Test-Json incorrectly parsed JSON as JObject, which failed if the root type was not an object, but array, string, number, etc. Michael Klement (@mklement0) suggested to change it to JToken which matches all types, which I verified to be a one-line fix.

Fixes #11384

PR Context

Test-Json currently fails if the root type is not an object, despite ConvertFrom-Json and ConvertTo-Json handling them without a problem. This leads to confusing case of 1 | ConvertTo-Json | Test-Json failing with a non-specific error "Cannot parse JSON".

This bug is most apparent when trying to validate a JSON schema where the root is not a single object, but instead an array of objects. However, as in example above, it also impacts cases without schema, where someone might use Test-Json as a shorthand for putting ConvertFrom-Json in a try-catch, which is exactly how it should be used when you don't care about content, just whether it is valid.

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