Assert Section Signals Invalid JSON For Array With String Values

[x80486]

I have checked the following:

• I have searched existing issues and found nothing related to my issue.

This bug is:

• making Bruno unusable for me
• slowing me down but I'm able to continue working
• annoying
• this feature was working in a previous version but is broken in the current release.

Bruno version

3.1.4

Operating System

macOS Tahoe 26.3.1 (a)

Describe the bug

I usually have some basic assertions for all requests. I noticed that Bruno is failing a simple res.body isJson assertion now for some responses that are just a collection of string values; for instance:

[
  "A55001213ZX0A"
]

.bru file to reproduce the bug

meta {
  name: Some Identifier
  type: http
}

get {
  url: {{api-host}}/resource/{{resource-id}}
  body: none
}

headers {
  Accept: application/json
}

vars:pre-request {
  resource-id: A55001213ZX0A
}

assert {
  res.status: eq 200
  res.body: isJson
}

Screenshots/Live demo link

N/A

[coderabbitai]

🔗 Related PRs

#6476 - fix: openapi spec with example values [merged]
#6488 - fix: JSON response examples being saved as [object Object] in YAML format [merged]
#7191 - fix: isJson assertion fails after res.setBody() with object in node-vm [merged]
#7207 - fix(cli): preserve request item type during import and fail on unsupported types [merged]
#7476 - fix: convert non-string variable values to strings during postman import [merged]

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