giscanner: change some internal field logic

Replace the 'allow_none' field on parameters with two separate fields:
'nullable' and 'optional'.

Currently, we use 'nullable' to mean the same thing as 'allow-none' for
normal (non-out) parameters.  For out parameters, we use the 'optional'
field instead.

Note that the special case for GCancellable and GAsyncReadyCallback is
already guarded by a check for being an in parameter, so we always use
'nullable' here.

On the .gir writer side, we decide which variable to consult when
writing the allow-none attribute depending on the parameter direction.

https://bugzilla.gnome.org/show_bug.cgi?id=660879

1 files changed, 6 insertions, 2 deletions

diff --git a/giscanner/girwriter.py b/giscanner/girwriter.py
index 304cf322..49d24bc4 100644
--- a/giscanner/girwriter.py
+++ b/giscanner/girwriter.py
@@ -239,8 +239,12 @@ class GIRWriter(XMLWriter):
         if parameter.transfer:
             attrs.append(('transfer-ownership',
                           parameter.transfer))
-        if parameter.allow_none:
-            attrs.append(('allow-none', '1'))
+        if parameter.nullable:
+            if parameter.direction != ast.PARAM_DIRECTION_OUT:
+                attrs.append(('allow-none', '1'))
+        if parameter.optional:
+            if parameter.direction == ast.PARAM_DIRECTION_OUT:
+                attrs.append(('allow-none', '1'))
         if parameter.scope:
             attrs.append(('scope', parameter.scope))
         if parameter.closure_name is not None: