Some fixes to processing expression parameters

Author: nyalldawson

python/plugins/processing/core/parameters.py

@@ -1251,12 +1251,13 @@ def getAsScriptCode(self):
     @classmethod
     def fromScriptCode(self, line):
         isOptional, name, definition = _splitParameterOptions(line)
-        descName = _createDescriptiveName(name)
-        default = definition.strip()[len('expression') + 1:]
-        if default:
-            return ParameterExpression(name, descName, default, optional=isOptional)
-        else:
-            return ParameterExpression(name, descName, optional=isOptional)
+        if definition.lower().strip().startswith('expression'):
+            descName = _createDescriptiveName(name)
+            default = definition.strip()[len('expression') + 1:]
+            if default:
+                return ParameterExpression(name, descName, default, optional=isOptional)
+            else:
+                return ParameterExpression(name, descName, optional=isOptional)
 
 
 class ParameterTable(ParameterDataObject):

python/plugins/processing/gui/wrappers.py

@@ -754,7 +754,10 @@ def setValue(self, value):
 
     def value(self):
         if self.dialogType in (DIALOG_STANDARD, DIALOG_BATCH):
-            return self.widget.asExpression()
+            try:
+                return self.widget.asExpression()
+            except:
+                return self.widget.expression()
         else:
             def validator(v):
                 return bool(v) or self.param.optional