Convert variable types before applying defaults

Author: Liam Cervante

internal/terraform/context_apply_test.go

@@ -12027,7 +12027,7 @@ output "out" {
 		Mode: plans.NormalMode,
 		SetVariables: InputValues{
 			"in": &InputValue{
-				Value: cty.MapVal(map[string]cty.Value{
+				Value: cty.ObjectVal(map[string]cty.Value{
 					"required": cty.StringVal("boop"),
 				}),
 				SourceType: ValueFromCaller,

internal/terraform/eval_variable.go

@@ -90,14 +90,6 @@ func prepareFinalInputVariableValue(addr addrs.AbsInputVariableInstance, raw *In
 		given = defaultVal // must be set, because we checked above that the variable isn't required
 	}
 
-	// Apply defaults from the variable's type constraint to the given value,
-	// unless the given value is null. We do not apply defaults to top-level
-	// null values, as doing so could prevent assigning null to a nullable
-	// variable.
-	if cfg.TypeDefaults != nil && !given.IsNull() {
-		given = cfg.TypeDefaults.Apply(given)
-	}
-
 	val, err := convert.Convert(given, convertTy)
 	if err != nil {
 		log.Printf("[ERROR] prepareFinalInputVariableValue: %s has unsuitable type\n  got:  %s\n  want: %s", addr, given.Type(), convertTy)
@@ -140,6 +132,14 @@ func prepareFinalInputVariableValue(addr addrs.AbsInputVariableInstance, raw *In
 		return cty.UnknownVal(cfg.Type), diags
 	}
 
+	// Apply defaults from the variable's type constraint to the given value,
+	// unless the given value is null. We do not apply defaults to top-level
+	// null values, as doing so could prevent assigning null to a nullable
+	// variable.
+	if cfg.TypeDefaults != nil && !val.IsNull() {
+		val = cfg.TypeDefaults.Apply(val)
+	}
+
 	// By the time we get here, we know:
 	// - val matches the variable's type constraint
 	// - val is definitely not cty.NilVal, but might be a null value if the given was already null.

internal/terraform/eval_variable_test.go

@@ -68,6 +68,15 @@ func TestPrepareFinalInputVariableValue(t *testing.T) {
 			nullable  = false
 			type      = string
 		}
+		variable "complex_type_with_nested_default_optional" {
+			type = set(object({
+				name = string
+				schedules = set(object({
+					name = string
+					cold_storage_after = optional(number, 10)
+				}))
+  			}))
+		}
 	`
 	cfg := testModuleInline(t, map[string]string{
 		"main.tf": cfgSrc,
@@ -399,6 +408,59 @@ func TestPrepareFinalInputVariableValue(t *testing.T) {
 			``,
 		},
 
+		// complex types
+
+		{
+			"complex_type_with_nested_default_optional",
+			cty.SetVal([]cty.Value{
+				cty.ObjectVal(map[string]cty.Value{
+					"name": cty.StringVal("test1"),
+					"schedules": cty.SetVal([]cty.Value{
+						cty.MapVal(map[string]cty.Value{
+							"name": cty.StringVal("daily"),
+						}),
+					}),
+				}),
+				cty.ObjectVal(map[string]cty.Value{
+					"name": cty.StringVal("test2"),
+					"schedules": cty.SetVal([]cty.Value{
+						cty.MapVal(map[string]cty.Value{
+							"name": cty.StringVal("daily"),
+						}),
+						cty.MapVal(map[string]cty.Value{
+							"name":               cty.StringVal("weekly"),
+							"cold_storage_after": cty.StringVal("0"),
+						}),
+					}),
+				}),
+			}),
+			cty.SetVal([]cty.Value{
+				cty.ObjectVal(map[string]cty.Value{
+					"name": cty.StringVal("test1"),
+					"schedules": cty.SetVal([]cty.Value{
+						cty.ObjectVal(map[string]cty.Value{
+							"name":               cty.StringVal("daily"),
+							"cold_storage_after": cty.NumberIntVal(10),
+						}),
+					}),
+				}),
+				cty.ObjectVal(map[string]cty.Value{
+					"name": cty.StringVal("test2"),
+					"schedules": cty.SetVal([]cty.Value{
+						cty.ObjectVal(map[string]cty.Value{
+							"name":               cty.StringVal("daily"),
+							"cold_storage_after": cty.NumberIntVal(10),
+						}),
+						cty.ObjectVal(map[string]cty.Value{
+							"name":               cty.StringVal("weekly"),
+							"cold_storage_after": cty.NumberIntVal(0),
+						}),
+					}),
+				}),
+			}),
+			``,
+		},
+
 		// sensitive
 		{
 			"constrained_string_sensitive_required",