Fix array manipulation bug with the zone settings resource.

[turbomaze]

This PR addresses a potential bug with the cloudflare_zone_settings_override resource. I was reviewing the implementation before provisioning it, and I encountered a bit of array manipulation code that might contain a bug. I haven't observed a problem in practice, but out of caution, I don't want to apply this resource until I'm sure it won't cause any problems for my zone.

The potential bug relates to how zone settings that must be fetched as single zone settings are removed from the zone settings list. I think there's an off-by-one type of error happening as the zone settings array is mutated.

NOTE: the code in this PR has never been tested or even ran

[github-actions[bot]]

changelog detected :white_check_mark:

[jacobbednarz]

@turbomaze are you able to add a test case that demonstrates the issue and the fix here? i'm not quite sure if this is actually changing the behaviour.

[turbomaze]

Unfortunately I won't be able to dig into the actual provider code to put together a proper test case. But here's some Go code demonstrating the issue and the resolution:

package main

import "fmt"

func main() {
	// current behavior, buggy
	arr := []int{0, 1, 2, 3, 4}
	indexesToCut := []int{0, 1}
	fmt.Println("expected", []int{2, 3, 4})

	for _, indexToCut := range indexesToCut {
		arr = append(arr[:indexToCut], arr[indexToCut+1:]...)
	}
	fmt.Println("current", arr)

	// proposed behavior, not buggy
	arr = []int{0, 1, 2, 3, 4}
	indexesToCut = []int{0, 1}

	offset := 0
	for _, indexToCut := range indexesToCut {
		adjustedIndexToCut := indexToCut - offset
		arr = append(arr[:adjustedIndexToCut], arr[adjustedIndexToCut+1:]...)
		offset += 1
	}

	fmt.Println("proposed", arr)
}

Output:

expected [2 3 4]
current [1 3 4]
proposed [2 3 4]

[jacobbednarz]

@turbomaze after you add the CHANGELOG entry (https://github.com/cloudflare/terraform-provider-cloudflare/pull/1925#issuecomment-1255585508) we can get this merged.

[turbomaze]

@turbomaze after you add the CHANGELOG entry (#1925 (comment)) we can get this merged.

Should be good now, thanks

[github-actions[bot]]

This functionality has been released in v3.25.0 of the Terraform Cloudflare Provider.

Please see the Terraform documentation on provider versioning or reach out if you need any assistance upgrading.

For further feature requests or bug reports with this functionality, please create a new GitHub issue following the template. Thank you!