PICARD-2213: Support for YAML export packages is mandatory again

INSTALL.md

@@ -11,6 +11,7 @@ Required:
 * [Python 3.6 or newer](http://python.org/download)
 * [PyQt 5.10 or newer](http://www.riverbankcomputing.co.uk/software/pyqt/download)
 * [Mutagen 1.37 or newer](https://mutagen.readthedocs.io/)
+* [PyYAML 5.1 or newer](https://pyyaml.org/)
 * [python-dateutil](https://dateutil.readthedocs.io/en/stable/)
 * gettext:
   * [Windows](https://mlocati.github.io/articles/gettext-iconv-windows.html)

picard/script/__init__.py

@@ -44,6 +44,8 @@ from enum import (
 import json
 import uuid
 
+import yaml
+
 from picard.config import get_config
 from picard.const import (
     DEFAULT_FILE_NAMING_FORMAT,
@@ -71,14 +73,6 @@ from picard.script.parser import (  # noqa: F401 # pylint: disable=unused-import
 )
 
 
-try:
-    import yaml
-    supports_script_package = True
-except ImportError:
-    yaml = None
-    supports_script_package = False
-
-
 class ScriptFunctionDocError(Exception):
     pass
 
@@ -139,7 +133,7 @@ class ScriptImportError(Exception):
         super().__init__(*args)
 
 
-class ScriptLiteral(str):
+class MultilineLiteral(str):
     @staticmethod
     def yaml_presenter(dumper, data):
         if data:
@@ -147,8 +141,7 @@ class ScriptLiteral(str):
         return dumper.represent_scalar("tag:yaml.org,2002:str", data, style="|")
 
 
-if yaml:
-    yaml.add_representer(ScriptLiteral, ScriptLiteral.yaml_presenter)
+yaml.add_representer(MultilineLiteral, MultilineLiteral.yaml_presenter)
 
 
 class PicardScript():
@@ -214,7 +207,7 @@ class PicardScript():
 
     @script.setter
     def script(self, value):
-        self._script = ScriptLiteral(value)
+        self._script = MultilineLiteral(value)
 
     @staticmethod
     def make_last_updated():
@@ -393,6 +386,14 @@ class FileNamingScript(PicardScript):
         self.license = license
         self.version = version
 
+    @property
+    def description(self):
+        return self._description
+
+    @description.setter
+    def description(self, value):
+        self._description = MultilineLiteral(value)
+
 
 def get_file_naming_script_presets():
     """Generator of preset example file naming script objects.

picard/ui/scripteditor.py

@@ -46,7 +46,6 @@ from picard.script import (
     ScriptImportError,
     ScriptParser,
     get_file_naming_script_presets,
-    supports_script_package,
 )
 from picard.util import (
     icontheme,
@@ -872,7 +871,7 @@ class ScriptEditorDialog(PicardDialog):
             if not file_content.strip():
                 self.output_file_error(FILE_ERROR_IMPORT, filename, _('The file was empty'))
                 return
-            if supports_script_package and file_type == self.FILE_TYPE_PACKAGE:
+            if file_type == self.FILE_TYPE_PACKAGE:
                 try:
                     script_item = FileNamingScript().create_from_yaml(file_content)
                 except ScriptImportError as error:
@@ -907,7 +906,7 @@ class ScriptEditorDialog(PicardDialog):
                 if ext and str(name).endswith('.' + ext):
                     filename = name
                 log.debug('Exporting naming script file: %s' % filename)
-                if supports_script_package and file_type == self.FILE_TYPE_PACKAGE:
+                if file_type == self.FILE_TYPE_PACKAGE:
                     script_text = script_item.to_yaml()
                 try:
                     with open(filename, 'w', encoding='utf8') as o_file:
@@ -925,12 +924,11 @@ class ScriptEditorDialog(PicardDialog):
                     dialog.exec_()
 
     def _get_dialog_filetypes(self):
-        file_types = []
-        if supports_script_package:
-            file_types.append(self.FILE_TYPE_PACKAGE)
-        file_types.append(self.FILE_TYPE_SCRIPT)
-        file_types.append(self.FILE_TYPE_ALL)
-        return ";;".join(file_types)
+        return ";;".join((
+            self.FILE_TYPE_PACKAGE,
+            self.FILE_TYPE_SCRIPT,
+            self.FILE_TYPE_ALL,
+        ))
 
     def reset_script(self):
         """Reset the script to the last saved value.

requirements.txt

@@ -7,4 +7,4 @@ pyobjc-core~=6.2; sys_platform == 'darwin'
 pyobjc-framework-Cocoa~=6.2; sys_platform == 'darwin'
 PyQt5~=5.10
 pywin32; sys_platform == 'win32'
-pyyaml>=5.1
+pyyaml~=5.1