Treat empty blocks with MinItems == 0 as optional

schemamd/behaviors.go

@@ -16,12 +16,17 @@ func childAttributeIsOptional(att *tfjson.SchemaAttribute) bool {
 	return att.Optional
 }
 
-// childBlockIsOptional returns true for blocks with with min items 0 and any required or optional children.
+// childBlockIsOptional returns true for blocks with with min items 0
+// which are either empty or have any required or optional children.
 func childBlockIsOptional(block *tfjson.SchemaBlockType) bool {
 	if block.MinItems > 0 {
 		return false
 	}
 
+	if len(block.Block.NestedBlocks) == 0 && len(block.Block.Attributes) == 0 {
+		return true
+	}
+
 	for _, childBlock := range block.Block.NestedBlocks {
 		if childBlockIsRequired(childBlock) {
 			return true

schemamd/behaviors_test.go

@@ -324,6 +324,16 @@ func TestChildBlockIsOptional(t *testing.T) {
 			},
 			false,
 		},
+		{
+			"empty block",
+			&tfjson.SchemaBlockType{
+				NestingMode: tfjson.SchemaNestingModeSingle,
+				Block: &tfjson.SchemaBlock{
+					Description: "This is an empty block.",
+				},
+			},
+			true,
+		},
 	} {
 		t.Run(c.name, func(t *testing.T) {
 			actual := childBlockIsOptional(c.block)