Dynamic block ignores block schema

[wata727]

Introduction

TFLint implicitly resolves dynamic blocks. For instance, it will return 2 blocks for the following configuration:

resource "aws_instance" "dynamic" {
  dynamic "ebs_block_device" {
    for_each = var.block_devices
    content {
      encrypted = false
    }
  }

  ebs_block_device {
    encrypted = false
  }
}

resources, _ := runner.GetResourceContent("aws_instance", &hclext.BodySchema{
	Blocks: []hclext.BlockSchema{
		{
			Type: "ebs_block_device",
			Body: &hclext.BodySchema{Attributes: []hclext.AttributeSchema{{Name: "encrypted"}}},
		},
	},
}, nil)

len(resources.Blocks[0].Body.Blocks) // => 2

But this dynamic block ignores the block type "ebs_block_device" and all dynamic blocks are returned.

Expected Behavior

It should return 2 blocks for the following configuration like

resource "aws_instance" "dynamic" {
  dynamic "network_interface" { # => should be ignored because this is not "ebs_block_device" block
    for_each = var.network_instances
    content {
      device_index = 0
    }
  }

  dynamic "ebs_block_device" {
    for_each = var.block_devices
    content {
      encrypted = false
    }
  }

  ebs_block_device {
    encrypted = false
  }
}

Actual behavior

3 blocks are returned.

resources, _ := runner.GetResourceContent("aws_instance", &hclext.BodySchema{
	Blocks: []hclext.BlockSchema{
		{
			Type: "ebs_block_device",
			Body: &hclext.BodySchema{Attributes: []hclext.AttributeSchema{{Name: "encrypted"}}},
		},
	},
}, nil)

len(resources.Blocks[0].Body.Blocks) // => 3

for _, block := range resources.Blocks[0].Body.Blocks {
	fmt.Printf("type: %s", block.Type)
}
// => type: network_interface
//    type: ebs_block_device
//    type: ebs_block_device

Step to Reproduce

See also terraform-linters/tflint-ruleset-aws#391

Additional Context

$ tflint -v
TFLint version 0.42.1
+ ruleset.aws (0.18.0)
+ ruleset.terraform (0.2.0-bundled)
$ terraform -v
Terraform v1.1.5
on darwin_arm64
+ provider registry.terraform.io/hashicorp/aws v4.36.1

[wata727]

This is a bug related to dynamic block resolution. schemaWithDynamic gets all dynamic blocks, ignoring the block schema.
https://github.com/terraform-linters/tflint/blob/v0.42.2/terraform/module.go#L183-L194

Ideally, resolveDynamicBlocks should exclude blocks with different block schemas, but it doesn't.
https://github.com/terraform-linters/tflint/blob/v0.42.2/terraform/module.go#L211-L214

The handling of dynamic block resolution may need to be improved. By delegating this responsibility to hclext package, it may be easier and clearer.