Diff output incorrectly double-quotes map keys on update

[alisdair]

Terraform Version

Terraform v1.1.8
on darwin_amd64
+ provider registry.terraform.io/hashicorp/aws v4.9.0

Terraform Configuration Files

provider "aws" {
  region = "us-east-1"
}

variable "use_tags" {
  default = false
}

locals {
  tags = {
    foo       = "my"
    "bar"     = "test"
    "foo/bar" = "my-test"
  }
}

resource "aws_instance" "web" {
  ami           = "ami-2757f631"
  instance_type = "t2.micro"

  tags = var.use_tags ? local.tags : null
}

Expected Behavior

  # aws_instance.web will be updated in-place
  ~ resource "aws_instance" "web" {
        id                                   = "i-005c16f62aeb7220a"
      ~ tags                                 = {
          + "bar"     = "test"
          + "foo"     = "my"
          + "foo/bar" = "my-test"
        }
      ~ tags_all                             = {
          + "bar"     = "test"
          + "foo"     = "my"
          + "foo/bar" = "my-test"
        }

Actual Behavior

  # aws_instance.web will be updated in-place
  ~ resource "aws_instance" "web" {
        id                                   = "i-005c16f62aeb7220a"
      ~ tags                                 = {
          + "bar"       = "test"
          + "foo"       = "my"
          + "\"foo/bar\"" = "my-test"
        }
      ~ tags_all                             = {
          + "bar"       = "test"
          + "foo"       = "my"
          + "\"foo/bar\"" = "my-test"
        }

Steps to Reproduce

Create a resource with no tags, then plan to add tags:

1. terraform init
2. terraform apply -auto-approve3.
3. terraform plan -var use_tags=true

References

• Reported by @stevehipwell in the post-merge comments of command/format: Correctly quote diff object keys #30766, which probably introduced this behaviour

[stevehipwell]

Thanks for the quick follow up and opening of the issue @alisdair!

[github-actions]

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