Fix the ability to ask for and save user input

command/meta_backend.go

@@ -869,7 +869,7 @@ func (m *Meta) backendInitFromConfig(c *configs.Backend) (backend.Backend, cty.V
 	b := f()
 
 	schema := b.ConfigSchema()
-	decSpec := schema.DecoderSpec()
+	decSpec := schema.NoneRequired().DecoderSpec()
 	configVal, hclDiags := hcldec.Decode(c.Config, decSpec, nil)
 	diags = diags.Append(hclDiags)
 	if hclDiags.HasErrors() {

command/meta_config.go

@@ -231,12 +231,10 @@ func (m *Meta) inputForSchema(given cty.Value, schema *configschema.Block) (cty.
 		return given, nil
 	}
 
-	givenVals := given.AsValueMap()
-	retVals := make(map[string]cty.Value, len(givenVals))
+	retVals := given.AsValueMap()
 	names := make([]string, 0, len(schema.Attributes))
 	for name, attrS := range schema.Attributes {
-		retVals[name] = givenVals[name]
-		if givenVal := givenVals[name]; attrS.Required && givenVal.IsNull() && attrS.Type.IsPrimitiveType() {
+		if attrS.Required && retVals[name].IsNull() && attrS.Type.IsPrimitiveType() {
 			names = append(names, name)
 		}
 	}