Add hclext.Blocks's OfType helper (#169)

Author: wata727

hclext/structure.go

@@ -158,6 +158,19 @@ func PartialContent(body hcl.Body, schema *BodySchema) (*BodyContent, hcl.Diagno
 	return ret, diags
 }
 
+// OfType filters the receiving block sequence by block type name,
+// returning a new block sequence including only the blocks of the
+// requested type.
+func (els Blocks) OfType(typeName string) Blocks {
+	ret := make(Blocks, 0)
+	for _, el := range els {
+		if el.Type == typeName {
+			ret = append(ret, el)
+		}
+	}
+	return ret
+}
+
 // ByType transforms the receiving block sequence into a map from type
 // name to block sequences of only that type.
 func (els Blocks) ByType() map[string]Blocks {