Try to use SetInt in case if possible

Allows to decode aliased int types, like time.Duration

decoder.go

@@ -91,7 +91,7 @@ func (d *decoder) decode(name string, node ast.Node, result reflect.Value) error
 		return d.decodeBool(name, node, result)
 	case reflect.Float64:
 		return d.decodeFloat(name, node, result)
-	case reflect.Int:
+	case reflect.Int, reflect.Int32, reflect.Int64:
 		return d.decodeInt(name, node, result)
 	case reflect.Interface:
 		// When we see an interface, we make our own thing
@@ -164,7 +164,11 @@ func (d *decoder) decodeInt(name string, node ast.Node, result reflect.Value) er
 				return err
 			}
 
-			result.Set(reflect.ValueOf(int(v)))
+			if result.Kind() == reflect.Interface {
+				result.Set(reflect.ValueOf(int(v)))
+			} else {
+				result.SetInt(v)
+			}
 			return nil
 		case token.STRING:
 			v, err := strconv.ParseInt(n.Token.Value().(string), 0, 0)
@@ -172,7 +176,11 @@ func (d *decoder) decodeInt(name string, node ast.Node, result reflect.Value) er
 				return err
 			}
 
-			result.Set(reflect.ValueOf(int(v)))
+			if result.Kind() == reflect.Interface {
+				result.Set(reflect.ValueOf(int(v)))
+			} else {
+				result.SetInt(v)
+			}
 			return nil
 		}
 	}

decoder_test.go

@@ -5,6 +5,7 @@ import (
 	"path/filepath"
 	"reflect"
 	"testing"
+	"time"
 
 	"github.com/davecgh/go-spew/spew"
 	"github.com/hashicorp/hcl/hcl/ast"
@@ -781,6 +782,21 @@ func TestDecode_intString(t *testing.T) {
 	}
 }
 
+func TestDecode_intStringAliased(t *testing.T) {
+	var value struct {
+		Count time.Duration
+	}
+
+	err := Decode(&value, testReadFile(t, "basic_int_string.hcl"))
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	if value.Count != time.Duration(3) {
+		t.Fatalf("bad: %#v", value.Count)
+	}
+}
+
 func TestDecode_Node(t *testing.T) {
 	// given
 	var value struct {