hcl2 length() of map issue

[traceypooh]

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Nomad version

Nomad v1.0.3

Operating system and Environment details

Mac mini

Issue

job.hcl:34,15-22: Error in function call; Call to function “length” failed: collection must be a list, a map or a tuple.

Reproduction steps

locals {
  nports = "${length({ "a" = "b"})}"
}

(see also https://discuss.hashicorp.com/t/hcl2-length-of-map-issue/20911/2 )

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[jrasell]

Hi @traceypooh and thanks for raising this issue. I can reproduce this locally but have not been able to figure the cause a the moment, so will label accordingly.

[tgross]

At first I suspected this was a quoting issue, but it looks like it fails with the same error even without quoting:

# map fails
locals {
  nports = length({ "a" = "b" })
}

# lists work fine
locals {
  nports = length(["a", "b"])
}

Suspecting that we actually have an "object" here and not a map, I tried using convert:

locals {
  nports = length(convert({"a" = "b"}, map(string)))
}

And that passes validation. One of the libraries we use is a little picky about object vs map but it looks like the documentation could use some improvement as well. I'll open a PR shortly with some doc fixes.

[traceypooh]

thanks y'all!
For now I've worked around with something like length(keys({ "a" = "b"}))

[traceypooh]

whoa, @jrasell -- your name kept running through my head and just finally realized where from. levant!! 😍

[github-actions]

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