“panic: runtime error: index out of range” using a combination of null and splat

[izeau]

Terraform Version

v0.12.24

Terraform Configuration Files

locals {
  x = concat([1, null]...)
}

Debug Output

https://gist.github.com/izeau/8be4f9671c27a2404eee74ca82a9a29c#file-trace-out

Crash Output

https://gist.github.com/izeau/8be4f9671c27a2404eee74ca82a9a29c#file-crash-log

Expected Behavior

I expected it to fail with an error, but not a panic. The generic one would have been nice:

Invalid value for "seqs" parameter: argument must not be null.

Actual Behavior

💥

Steps to Reproduce

$ terraform console <<< 'concat([1, null]...)'

Additional Context

References

[danieldreier]

@izeau thanks! I've reproduced this and am seeing the same behavior. Even a terraform validate on this causes the panic. We're pretty heads-down on 0.13 feature work right now, but are hoping to do a big clean-up of known panics and I'm hoping we can come back to this at that point.

[ghost]

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