fix: Update Terragrunt flag for v0.85.0+ compatibility

[matthewgulliver]

• Fixes Terratest fails with Terragrunt v0.85.0+ due to deprecated --terragrunt-non-interactive flag #1587

Description

Updates Terratest to be compatible with Terragrunt v0.85.0+ by replacing the deprecated --terragrunt-non-interactive flag with the new --non-interactive flag.
This resolves test failures that occur when using modern Terragrunt versions due to Terragrunt's CLI redesign that removed all --terragrunt-* prefixed flags in favor of shorter alternatives.

Changes Made

• File: modules/terraform/cmd.go
• Change: Line 59 updated from --terragrunt-non-interactive to --non-interactive
• Documentation: Added comment explaining the change with reference to Terragrunt CLI redesign docs

Testing

✅ Verified with Terragrunt v0.86.2, Go v1.24.2 on Ubuntu 24.04
✅ All terragrunt tests pass: TestTerragruntExample, TestTerragruntConsole

Backward Compatibility

This change maintains compatibility:

• ✅ Terragrunt v0.85.0+: Uses new --non-interactive flag
• ✅ Earlier versions: Also support --non-interactive (flag existed before deprecation)

TODOs

• Update the code
• Run the relevant tests successfully
• Ensure no 3rd party code issues (N/A)
• Include release notes
• Verify fix works with multiple Terragrunt versions

Release Notes (draft)

Updated Terratest Terragrunt integration to use --non-interactive flag instead of deprecated --terragrunt-non-interactive flag for compatibility with Terragrunt v0.85.0+.

Migration Guide

No migration required for users. This is an internal change to maintain compatibility with modern Terragrunt versions. Users may need to update their Terragrunt installations if using very old versions, but this change is backward compatible with all supported Terragrunt releases.

References

• Terragrunt CLI Redesign Documentation
• Terragrunt v0.85.0 Release
• Related Issue #1586

[yhakbar]

This is a breaking change in that it raises the minimum required version of Terragrunt to v0.73.0. We'd want the docs updated accordingly.

[james00012]

Hi @matthewgulliver friendly ping on the comment to address above. Are you still working on this PR?

[matthewgulliver]

Hey @james00012, thanks for the reminder. I've added Terragrunt v0.73.0+ requirement to the Requirements section in docs/_docs/01_getting-started/quick-start.md. Let me know if any further changes are needed.

[steffsas]

When is this going to be merged? This is a blocker of using Terratest and Terragrunt with newer versions.

[fanovilla]

hi team, yep keen to have this in a new release; @james00012

[matthewgulliver]

Hey @james00012 @yhakbar,

Just checking in to see if there was anything I'd missed or whether you guys have any further requirements for the PR? If so, just let me know and I'll make the necessary changes.

Thanks,
Matt.