Describe the Bug

Custom command steps that invoke atmos terraform subcommands fail with the error:

exec: "terraform": cannot run executable found relative to current directory

This only occurs when the command is executed through a custom command step. Running the exact same atmos terraform command directly from the shell succeeds without issues.

For example, this fails:

atmos util lock <component> -s <stack>

But the underlying command it executes works fine when run directly:

atmos terraform providers lock -platform=windows_amd64 -platform=darwin_amd64 -platform=linux_amd64 <component> -s <stack>

The toolchain feature is enabled with .tool-versions managing terraform and atmos versions.

Expected Behavior

The toolchain should prepend absolute paths to PATH (e.g., /absolute/path/to/project/.tools/bin/hashicorp/terraform/1.14.2) so that subprocess invocations resolve toolchain binaries correctly regardless of working directory context.

Steps to Reproduce

1. Configure atmos.yaml with toolchain enabled:

    toolchain:
      file_path: ".tool-versions"
      install_path: ".tools"

    components:
      terraform:
        command: terraform

2. Create .tool-versions:

    atmos 1.206.2
    terraform 1.14.2

3. Define a custom command in .atmos.d/commands.yaml:

    commands:
      - name: util
        commands:
          - name: lock
            description: Execute 'terraform lock' command for all OS platforms
            arguments:
              - name: component
                description: Name of the component
            flags:
              - name: stack
                shorthand: s
                description: Name of the stack
                required: true
            steps:
              - atmos terraform providers lock -platform=windows_amd64 -platform=darwin_amd64 -platform=linux_amd64 {{ .Arguments.component }} -s {{ .Flags.stack }}

4. Run the custom command:

    atmos util lock <component> -s <stack>

5. Observe the error:

    Error: exec: "terraform": cannot run executable found relative to current directory

6. Verify by adding a debug step (echo "PATH=$PATH") — PATH shows:

    PATH=.tools/bin/cloudposse/atmos/1.206.2:.tools/bin/hashicorp/terraform/1.14.2:/usr/local/bin:...

7. Running the same command directly works:

    atmos terraform providers lock -platform=windows_amd64 -platform=darwin_amd64 -platform=linux_amd64 <component> -s <stack>

Screenshots

No response

Environment

• Atmos version: 1.206.2
• Terraform version: 1.14.2
• OS: macOS (darwin/arm64)

Additional Context

The root cause is in the toolchain PATH setup logic. When atmos prepends toolchain directories to PATH for custom command execution, it uses relative paths like .tools/bin/hashicorp/terraform/1.14.2 instead of resolving them to absolute paths first. This conflicts with Go's exec.LookPath security change in Go 1.19 that rejects executables found via relative PATH entries.

Current workaround is to override PATH in the custom command step with absolute paths:

steps:
  - >-
    PATH="$(pwd)/.tools/bin/cloudposse/atmos/1.206.2:$(pwd)/.tools/bin/hashicorp/terraform/1.14.2:$PATH"
    atmos terraform providers lock ...