From ed6d4bf93b5d9b862dae35dcd605f4d609d3dd7c Mon Sep 17 00:00:00 2001
From: Kazuma Watanabe <watassbass@gmail.com>
Date: Wed, 30 Aug 2023 15:05:21 +0000
Subject: [PATCH] ext/typeexpr: Avoid refinements on dynamic values

---
 ext/typeexpr/defaults.go      |  2 +-
 ext/typeexpr/defaults_test.go | 17 +++++++++++++++++
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/ext/typeexpr/defaults.go b/ext/typeexpr/defaults.go
index 43a2539d..d3d6be29 100644
--- a/ext/typeexpr/defaults.go
+++ b/ext/typeexpr/defaults.go
@@ -95,7 +95,7 @@ func (d *Defaults) apply(v cty.Value) cty.Value {
 				}
 				values[key] = defaultValue
 			}
-			if defaultRng := defaultValue.Range(); defaultRng.DefinitelyNotNull() {
+			if defaultRng := defaultValue.Range(); defaultRng.DefinitelyNotNull() && values[key].Type() != cty.DynamicPseudoType {
 				values[key] = values[key].RefineNotNull()
 			}
 		}
diff --git a/ext/typeexpr/defaults_test.go b/ext/typeexpr/defaults_test.go
index 5f0588f5..dc3a3f42 100644
--- a/ext/typeexpr/defaults_test.go
+++ b/ext/typeexpr/defaults_test.go
@@ -898,6 +898,23 @@ func TestDefaults_Apply(t *testing.T) {
 				"foo": cty.UnknownVal(cty.String).RefineNotNull(),
 			}),
 		},
+		"optional attribute with dynamic value can be null": {
+			defaults: &Defaults{
+				Type: cty.ObjectWithOptionalAttrs(map[string]cty.Type{
+					"foo": cty.String,
+				}, []string{"foo"}),
+				DefaultValues: map[string]cty.Value{
+					"foo": cty.StringVal("bar"), // Important: default is non-null
+				},
+			},
+			value: cty.ObjectVal(map[string]cty.Value{
+				"foo": cty.DynamicVal,
+			}),
+			want: cty.ObjectVal(map[string]cty.Value{
+				// The default value is itself non-null, but dynamic value cannot be refined.
+				"foo": cty.DynamicVal,
+			}),
+		},
 	}
 
 	for name, tc := range testCases {