crash retrieving map with interpolated key

[blalor]

Terraform Version

v0.7.5

Affected Resource(s)

This appears to be an issue with the core.

Terraform Configuration Files

Attached: tf-reproduce.zip

modules/subnets/main.tf contains a map output:

output "vpcs" {
    value = "${map(
        "dev_aws_gen_us-east-1", "10.112.0.0/19"
    )}"
}

It's referenced in main.tf like

resource "aws_vpc" "default" {
    cidr_block = "${module.subnets.vpcs[format("%s_%s_%s_%s", var.environment, var.provider, var.account, var.region)]}"
}

Panic Output

crash.log.txt

Expected Behavior

terraform plan should have shown a plan to create an aws_vpc resource.

Actual Behavior

💣🔥
panic: runtime error: index out of range

Steps to Reproduce

1. unpack attached zip
2. run terraform get
3. run terraform plan

If cidr_block is changed to "${module.subnets.vpcs["dev_aws_gen_us-east-1"]}" the apply works fine.

References

Are there any other GitHub issues (open or closed) or Pull Requests that should be linked here? For example:

• outputting maps not working #8384

[jbardin]

Hi @blalor,

Thanks for the report and reproduction. I don't think this has anything to do with modules, it appears to be the format inside the map index that is throwing off the interpolator.

This reduced config crashes with apply

variable map {
    default = {
        a = "b"
    }
}

output "formatted_index" {
    value = "${var.map[format("%s", "a")]}"
}

[ghost]

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