[IMP] qweb: t-call tags have an optionnal t-lang attribute to make translations easier

openerp/addons/base/ir/ir_qweb.py

@@ -432,6 +432,14 @@ class QWeb(orm.AbstractModel):
 
     def render_tag_call(self, element, template_attributes, generated_attributes, qwebcontext):
         d = qwebcontext.copy()
+
+        if 'lang' in template_attributes:
+            init_lang = d.context.get('lang', 'en_US')
+            lang = template_attributes['lang']
+            d.context['lang'] = self.eval(lang, d) or lang
+            if not self.pool['res.lang'].search(d.cr, d.uid, [('code', '=', lang)], count=True, context=d.context):
+                _logger.info("'%s' is not a valid language code, is an empty field or is not installed, falling back to en_US", lang)
+
         d[0] = self.render_element(element, template_attributes, generated_attributes, d)
         cr = d.get('request') and d['request'].cr or None
         uid = d.get('request') and d['request'].uid or None
@@ -441,7 +449,14 @@ class QWeb(orm.AbstractModel):
             template = int(template)
         except ValueError:
             pass
-        return self.render(cr, uid, template, d)
+
+        res = self.render(cr, uid, template, d)
+
+        # we need to reset the lang after the rendering
+        if 'lang' in template_attributes:
+            d.context['lang'] = init_lang
+
+        return res
 
     def render_tag_call_assets(self, element, template_attributes, generated_attributes, qwebcontext):
         """ This special 't-call' tag can be used in order to aggregate/minify javascript and css assets"""