Terraform: Panic/crash when running 'terraform init -from-module=' when module contains another module

[tamsky]

Terraform Version: Terraform v0.12.9

Terraform Configuration Files

I've created a repo that contains a minimal example that triggers the crash:

• https://github.com/tamsky/terraform-0.12.9-init-from-module-crash-example

Invoke repo with make crash or make nocrash

Debug Output

I'll assume the crash.log file below is sufficient.

Crash Output

• https://github.com/tamsky/terraform-0.12.9-init-from-module-crash-example/blob/master/crash.log

Expected Behavior

terraform init -from-module=... should initialize without panic

Actual Behavior

panic.

Steps to Reproduce

run make crash in above linked example repo.

References

• #21653

[tamsky]

https://github.com/hashicorp/terraform/issues/21653#issuecomment-500051495 (from Jun 7 2019):

… something about calling init -from-module=foo on a module foo that itself contains a module with source set to a relative path causes a crash.

this appears to still be true

[tamsky]

/cc @pselle -- as they were involved in #21653

[askoriy]

Duplicate #22973

[danieldreier]

I have reproduced this on 0.12.26 and 0.13.0 beta 1 using make crash. Thank you for the excellent reproduction case!

[mildwonkey]

🎉 This has been fixed, and I managed to get it merged just in time for our next Terraform v0.13-beta release!

[hashibot[bot]]

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