allow for top level terraform flag assignment

[ThisGuyCodes]

fixes #517

also adds tests for FormatTerraformBackendConfigAsArgs

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This change is 

[brikis98]

I'm a bit confused by this PR. Is it missing files? The changes seem to affect how Terraform sets -var flags rather than -backend-config flags?

[ThisGuyCodes]

@brikis98 FormatTerraformBackendConfigAsArgs uses the generic formatTerraformArgs, which is what I modified:

terratest/modules/terraform/format.go

Lines 71 to 75 in 719caf2

	// FormatTerraformBackendConfigAsArgs formats the given variables as backend config args for Terraform (e.g. of the
	// format -backend-config=key=value).
	func FormatTerraformBackendConfigAsArgs(vars map[string]interface{}) []string {
	return formatTerraformArgs(vars, "-backend-config", false)
	}

[ThisGuyCodes]

oh I feel silly. That's the wrong test. I'll get back to you.

[brikis98]

Ah, OK, this makes more sense now!

Could you add comments to terraform.Options to indicate that terraform.KeyOnly can be used as a value in the BackendConfig map to indicate only the key should be passed to Terraform?

[brikis98]

Could you add comments to terraform.Options to indicate that terraform.KeyOnly can be used as a value in the BackendConfig map to indicate only the key should be passed to Terraform?

Bumping this one up too :)

[jai]

@ThisGuyCodes lmk if you could use a hand on this, could deff use this feature.

[ThisGuyCodes]

bump? (4 years later)