language: Add translation-domain

This allows you to set the translation domain of a blueprint file.

blueprintcompiler/language/translation_domain.py

@@ -0,0 +1,31 @@
+# translation_domain.py
+#
+# Copyright 2022 James Westman <james@jwestman.net>
+#
+# This file is free software; you can redistribute it and/or modify it
+# under the terms of the GNU Lesser General Public License as
+# published by the Free Software Foundation; either version 3 of the
+# License, or (at your option) any later version.
+#
+# This file is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+# SPDX-License-Identifier: LGPL-3.0-or-later
+
+from .common import *
+
+
+class TranslationDomain(AstNode):
+    grammar = Statement(
+        "translation-domain",
+        UseQuoted("domain"),
+    )
+
+    @property
+    def domain(self):
+        return self.tokens["domain"]

blueprintcompiler/language/ui.py

@@ -26,6 +26,7 @@ from .gobject_object import Object
 from .gtk_menu import Menu, menu
 from .gtkbuilder_template import Template
 from .imports import GtkDirective, Import
+from .translation_domain import TranslationDomain
 
 
 class UI(AstNode):
@@ -34,6 +35,7 @@ class UI(AstNode):
     grammar = [
         GtkDirective,
         ZeroOrMore(Import),
+        Optional(TranslationDomain),
         Until(
             AnyOf(
                 Template,
@@ -75,6 +77,14 @@ class UI(AstNode):
     def gtk_decl(self) -> GtkDirective:
         return self.children[GtkDirective][0]
 
+    @property
+    def translation_domain(self) -> T.Optional[TranslationDomain]:
+        domains = self.children[TranslationDomain]
+        if len(domains):
+            return domains[0]
+        else:
+            return None
+
     @property
     def contents(self) -> T.List[T.Union[Object, Template, Menu]]:
         return [

blueprintcompiler/outputs/xml/__init__.py

@@ -12,6 +12,9 @@ class XmlOutput(OutputFormat):
         return xml.result
 
     def _emit_ui(self, ui: UI, xml: XmlEmitter):
+        if domain := ui.translation_domain:
+            xml.start_tag("interface", domain=domain.domain)
+        else:
             xml.start_tag("interface")
 
         self._emit_gtk_directive(ui.gtk_decl, xml)

docs/reference/document_root.rst

@@ -10,7 +10,7 @@ Document Root
 
 .. rst-class:: grammar-block
 
-   Root = :ref:`GtkDecl<Syntax GtkDecl>` (:ref:`Using<Syntax Using>`)* ( :ref:`Template<Syntax Template>` | :ref:`Menu<Syntax Menu>` | :ref:`Object<Syntax Object>` )* EOF
+   Root = :ref:`GtkDecl<Syntax GtkDecl>` (:ref:`Using<Syntax Using>`)* (:ref:`TranslationDomain<Syntax TranslationDomain>`)? ( :ref:`Template<Syntax Template>` | :ref:`Menu<Syntax Menu>` | :ref:`Object<Syntax Object>` )* EOF
 
 A blueprint document consists of a :ref:`GTK declaration<Syntax GtkDecl>`, one sor more :ref:`imports<Syntax Using>`, and a list of :ref:`objects<Syntax Object>` and/or a :ref:`template<Syntax Template>`.
 
@@ -72,3 +72,17 @@ Example
 
    // Import libadwaita
    using Adw 1;
+
+
+.. _Syntax TranslationDomain:
+
+Translation Domain
+------------------
+
+.. rst-class:: grammar-block
+
+   TranslationDomain = 'translation-domain' <domain::ref:`QUOTED<Syntax QUOTED>`> ';'
+
+The translation domain is used to look up translations for translatable strings in the blueprint file. If no translation domain is specified, strings will be looked up in the program's global domain.
+
+See `Gtk.Builder:translation-domain <https://docs.gtk.org/gtk4/property.Builder.translation-domain.html>`_ for more information.

tests/samples/translation_domain.blp

@@ -0,0 +1,3 @@
+using Gtk 4.0;
+
+translation-domain "blueprint-tests";

tests/samples/translation_domain.ui

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+DO NOT EDIT!
+This file was @generated by blueprint-compiler. Instead, edit the
+corresponding .blp file and regenerate this file with blueprint-compiler.
+-->
+<interface domain="blueprint-tests">
+  <requires lib="gtk" version="4.0"/>
+</interface>