Emit pointers for nullable enum columns when emit_pointers_for_null_types is set

Closes #3276. When emit_pointers_for_null_types is true (PostgreSQL with
pgx/v4 or pgx/v5), nullable enum columns are now generated as pointers
(*UserRole) instead of the NullUserRole wrapper struct, matching the
existing behavior for other nullable types.

To preserve the previous behavior when upgrading, set
emit_pointers_for_null_enum_types: false. When explicitly set, this flag
overrides emit_pointers_for_null_types for enums only, so it can also be
used to opt into the pointer treatment for enums without enabling it for
every other null type.

https://claude.ai/code/session_01K2xVtbacEbjbA9ymg6dPtr

Author: claude

docs/reference/config.md

@@ -158,7 +158,9 @@ The `gen` mapping supports the following keys:
 - `emit_methods_with_db_argument`:
   - If true, generated methods will accept a DBTX argument instead of storing a DBTX on the `*Queries` struct. Defaults to `false`.
 - `emit_pointers_for_null_types`:
-  - If true, generated types for nullable columns are emitted as pointers (ie. `*string`) instead of `database/sql` null types (ie. `NullString`). Currently only supported for PostgreSQL if `sql_package` is `pgx/v4` or `pgx/v5`, and for SQLite. Defaults to `false`.
+  - If true, generated types for nullable columns are emitted as pointers (ie. `*string`) instead of `database/sql` null types (ie. `NullString`). Currently only supported for PostgreSQL if `sql_package` is `pgx/v4` or `pgx/v5`, and for SQLite. Defaults to `false`. Nullable enum columns also follow this setting unless `emit_pointers_for_null_enum_types` is set.
+- `emit_pointers_for_null_enum_types`:
+  - Overrides `emit_pointers_for_null_types` for nullable enum columns only. When `true`, nullable enum columns are emitted as pointers (ie. `*UserRole`). When `false`, nullable enum columns use the generated `NullUserRole` wrapper struct even if `emit_pointers_for_null_types` is true. Set this to `false` to keep the pre-v1.31 behavior when upgrading. Only applies to PostgreSQL with `sql_package` `pgx/v4` or `pgx/v5`.
 - `emit_enum_valid_method`:
   - If true, generate a Valid method on enum types,
     indicating whether a string is a valid enum value.
@@ -441,7 +443,9 @@ Each mapping in the `packages` collection has the following keys:
 - `emit_methods_with_db_argument`:
   - If true, generated methods will accept a DBTX argument instead of storing a DBTX on the `*Queries` struct. Defaults to `false`.
 - `emit_pointers_for_null_types`:
-  - If true and `sql_package` is set to `pgx/v4` or `pgx/v5`, generated types for nullable columns are emitted as pointers (ie. `*string`) instead of `database/sql` null types (ie. `NullString`). Defaults to `false`.
+  - If true and `sql_package` is set to `pgx/v4` or `pgx/v5`, generated types for nullable columns are emitted as pointers (ie. `*string`) instead of `database/sql` null types (ie. `NullString`). Defaults to `false`. Nullable enum columns also follow this setting unless `emit_pointers_for_null_enum_types` is set.
+- `emit_pointers_for_null_enum_types`:
+  - Overrides `emit_pointers_for_null_types` for nullable enum columns only. When `true`, nullable enum columns are emitted as pointers (ie. `*UserRole`). When `false`, nullable enum columns use the generated `NullUserRole` wrapper struct even if `emit_pointers_for_null_types` is true. Set this to `false` to keep the pre-v1.31 behavior when upgrading. Only applies to PostgreSQL with `sql_package` `pgx/v4` or `pgx/v5`.
 - `emit_enum_valid_method`:
   - If true, generate a Valid method on enum types,
     indicating whether a string is a valid enum value.

internal/codegen/golang/gen.go

@@ -396,7 +396,8 @@ func filterUnusedStructs(enums []Enum, structs []Struct, queries []Query) ([]Enu
 	for _, enum := range enums {
 		_, keep := keepTypes[enum.Name]
 		_, keepNull := keepTypes["Null"+enum.Name]
-		if keep || keepNull {
+		_, keepPointer := keepTypes["*"+enum.Name]
+		if keep || keepNull || keepPointer {
 			keepEnums = append(keepEnums, enum)
 		}
 	}

internal/codegen/golang/opts/options.go

@@ -10,41 +10,43 @@ import (
 )
 
 type Options struct {
-	EmitInterface               bool              `json:"emit_interface" yaml:"emit_interface"`
-	EmitJsonTags                bool              `json:"emit_json_tags" yaml:"emit_json_tags"`
-	JsonTagsIdUppercase         bool              `json:"json_tags_id_uppercase" yaml:"json_tags_id_uppercase"`
-	EmitDbTags                  bool              `json:"emit_db_tags" yaml:"emit_db_tags"`
-	EmitPreparedQueries         bool              `json:"emit_prepared_queries" yaml:"emit_prepared_queries"`
-	EmitExactTableNames         bool              `json:"emit_exact_table_names,omitempty" yaml:"emit_exact_table_names"`
-	EmitEmptySlices             bool              `json:"emit_empty_slices,omitempty" yaml:"emit_empty_slices"`
-	EmitExportedQueries         bool              `json:"emit_exported_queries" yaml:"emit_exported_queries"`
-	EmitResultStructPointers    bool              `json:"emit_result_struct_pointers" yaml:"emit_result_struct_pointers"`
-	EmitParamsStructPointers    bool              `json:"emit_params_struct_pointers" yaml:"emit_params_struct_pointers"`
-	EmitMethodsWithDbArgument   bool              `json:"emit_methods_with_db_argument,omitempty" yaml:"emit_methods_with_db_argument"`
-	EmitPointersForNullTypes    bool              `json:"emit_pointers_for_null_types" yaml:"emit_pointers_for_null_types"`
-	EmitEnumValidMethod         bool              `json:"emit_enum_valid_method,omitempty" yaml:"emit_enum_valid_method"`
-	EmitAllEnumValues           bool              `json:"emit_all_enum_values,omitempty" yaml:"emit_all_enum_values"`
-	EmitSqlAsComment            bool              `json:"emit_sql_as_comment,omitempty" yaml:"emit_sql_as_comment"`
-	JsonTagsCaseStyle           string            `json:"json_tags_case_style,omitempty" yaml:"json_tags_case_style"`
-	Package                     string            `json:"package" yaml:"package"`
-	Out                         string            `json:"out" yaml:"out"`
-	Overrides                   []Override        `json:"overrides,omitempty" yaml:"overrides"`
-	Rename                      map[string]string `json:"rename,omitempty" yaml:"rename"`
-	SqlPackage                  string            `json:"sql_package" yaml:"sql_package"`
-	SqlDriver                   string            `json:"sql_driver" yaml:"sql_driver"`
-	OutputBatchFileName         string            `json:"output_batch_file_name,omitempty" yaml:"output_batch_file_name"`
-	OutputDbFileName            string            `json:"output_db_file_name,omitempty" yaml:"output_db_file_name"`
-	OutputModelsFileName        string            `json:"output_models_file_name,omitempty" yaml:"output_models_file_name"`
-	OutputQuerierFileName       string            `json:"output_querier_file_name,omitempty" yaml:"output_querier_file_name"`
-	OutputCopyfromFileName      string            `json:"output_copyfrom_file_name,omitempty" yaml:"output_copyfrom_file_name"`
-	OutputFilesSuffix           string            `json:"output_files_suffix,omitempty" yaml:"output_files_suffix"`
-	InflectionExcludeTableNames []string          `json:"inflection_exclude_table_names,omitempty" yaml:"inflection_exclude_table_names"`
-	WrapErrors                  bool              `json:"wrap_errors,omitempty" yaml:"wrap_errors"`
-	QueryParameterLimit         *int32            `json:"query_parameter_limit,omitempty" yaml:"query_parameter_limit"`
-	OmitSqlcVersion             bool              `json:"omit_sqlc_version,omitempty" yaml:"omit_sqlc_version"`
-	OmitUnusedStructs           bool              `json:"omit_unused_structs,omitempty" yaml:"omit_unused_structs"`
-	BuildTags                   string            `json:"build_tags,omitempty" yaml:"build_tags"`
-	Initialisms                 *[]string         `json:"initialisms,omitempty" yaml:"initialisms"`
+	EmitInterface             bool `json:"emit_interface" yaml:"emit_interface"`
+	EmitJsonTags              bool `json:"emit_json_tags" yaml:"emit_json_tags"`
+	JsonTagsIdUppercase       bool `json:"json_tags_id_uppercase" yaml:"json_tags_id_uppercase"`
+	EmitDbTags                bool `json:"emit_db_tags" yaml:"emit_db_tags"`
+	EmitPreparedQueries       bool `json:"emit_prepared_queries" yaml:"emit_prepared_queries"`
+	EmitExactTableNames       bool `json:"emit_exact_table_names,omitempty" yaml:"emit_exact_table_names"`
+	EmitEmptySlices           bool `json:"emit_empty_slices,omitempty" yaml:"emit_empty_slices"`
+	EmitExportedQueries       bool `json:"emit_exported_queries" yaml:"emit_exported_queries"`
+	EmitResultStructPointers  bool `json:"emit_result_struct_pointers" yaml:"emit_result_struct_pointers"`
+	EmitParamsStructPointers  bool `json:"emit_params_struct_pointers" yaml:"emit_params_struct_pointers"`
+	EmitMethodsWithDbArgument bool `json:"emit_methods_with_db_argument,omitempty" yaml:"emit_methods_with_db_argument"`
+	EmitPointersForNullTypes  bool `json:"emit_pointers_for_null_types" yaml:"emit_pointers_for_null_types"`
+	// nil inherits EmitPointersForNullTypes; non-nil overrides for enums only.
+	EmitPointersForNullEnumTypes *bool             `json:"emit_pointers_for_null_enum_types,omitempty" yaml:"emit_pointers_for_null_enum_types"`
+	EmitEnumValidMethod          bool              `json:"emit_enum_valid_method,omitempty" yaml:"emit_enum_valid_method"`
+	EmitAllEnumValues            bool              `json:"emit_all_enum_values,omitempty" yaml:"emit_all_enum_values"`
+	EmitSqlAsComment             bool              `json:"emit_sql_as_comment,omitempty" yaml:"emit_sql_as_comment"`
+	JsonTagsCaseStyle            string            `json:"json_tags_case_style,omitempty" yaml:"json_tags_case_style"`
+	Package                      string            `json:"package" yaml:"package"`
+	Out                          string            `json:"out" yaml:"out"`
+	Overrides                    []Override        `json:"overrides,omitempty" yaml:"overrides"`
+	Rename                       map[string]string `json:"rename,omitempty" yaml:"rename"`
+	SqlPackage                   string            `json:"sql_package" yaml:"sql_package"`
+	SqlDriver                    string            `json:"sql_driver" yaml:"sql_driver"`
+	OutputBatchFileName          string            `json:"output_batch_file_name,omitempty" yaml:"output_batch_file_name"`
+	OutputDbFileName             string            `json:"output_db_file_name,omitempty" yaml:"output_db_file_name"`
+	OutputModelsFileName         string            `json:"output_models_file_name,omitempty" yaml:"output_models_file_name"`
+	OutputQuerierFileName        string            `json:"output_querier_file_name,omitempty" yaml:"output_querier_file_name"`
+	OutputCopyfromFileName       string            `json:"output_copyfrom_file_name,omitempty" yaml:"output_copyfrom_file_name"`
+	OutputFilesSuffix            string            `json:"output_files_suffix,omitempty" yaml:"output_files_suffix"`
+	InflectionExcludeTableNames  []string          `json:"inflection_exclude_table_names,omitempty" yaml:"inflection_exclude_table_names"`
+	WrapErrors                   bool              `json:"wrap_errors,omitempty" yaml:"wrap_errors"`
+	QueryParameterLimit          *int32            `json:"query_parameter_limit,omitempty" yaml:"query_parameter_limit"`
+	OmitSqlcVersion              bool              `json:"omit_sqlc_version,omitempty" yaml:"omit_sqlc_version"`
+	OmitUnusedStructs            bool              `json:"omit_unused_structs,omitempty" yaml:"omit_unused_structs"`
+	BuildTags                    string            `json:"build_tags,omitempty" yaml:"build_tags"`
+	Initialisms                  *[]string         `json:"initialisms,omitempty" yaml:"initialisms"`
 
 	InitialismsMap map[string]struct{} `json:"-" yaml:"-"`
 }

internal/codegen/golang/postgresql_type.go

@@ -39,6 +39,10 @@ func postgresType(req *plugin.GenerateRequest, options *opts.Options, col *plugi
 	notNull := col.NotNull || col.IsArray
 	driver := parseDriver(options.SqlPackage)
 	emitPointersForNull := driver.IsPGX() && options.EmitPointersForNullTypes
+	emitPointersForNullEnums := emitPointersForNull
+	if options.EmitPointersForNullEnumTypes != nil {
+		emitPointersForNullEnums = driver.IsPGX() && *options.EmitPointersForNullEnumTypes
+	}
 
 	switch columnType {
 	case "serial", "serial4", "pg_catalog.serial4":
@@ -582,10 +586,14 @@ func postgresType(req *plugin.GenerateRequest, options *opts.Options, col *plugi
 						}
 						return StructName(schema.Name+"_"+enum.Name, options)
 					} else {
+						nullPrefix := "Null"
+						if emitPointersForNullEnums {
+							nullPrefix = "*"
+						}
 						if schema.Name == req.Catalog.DefaultSchema {
-							return "Null" + StructName(enum.Name, options)
+							return nullPrefix + StructName(enum.Name, options)
 						}
-						return "Null" + StructName(schema.Name+"_"+enum.Name, options)
+						return nullPrefix + StructName(schema.Name+"_"+enum.Name, options)
 					}
 				}
 			}