[gjs: 1/2] object: Fix write-only properties

[Cosimo Cecchi <cosimoc src gnome org>]

commit 71324d9dbe6b559ee635b902d27348fd6849a54b
Author: Philip Chimento <philip chimento gmail com>
Date:   Sun Oct 21 15:05:11 2018 +0100

    object: Fix write-only properties
    
    Since the property refactor, write-only properties have not been working.
    The problem was that a getter and setter function were not defined for
    them, because is_gobject_property_name() did not consider them to be
    properties. Now, the setter function works as normal while the getter
    function just pretends a write-only property has the value of undefined.
    
    The test is marked pending until a test is added to the
    gobject-introspection test suite.

 gi/object.cpp                                    | 15 ++++++---------
 installed-tests/js/testEverythingEncapsulated.js | 10 ++++++++++
 2 files changed, 16 insertions(+), 9 deletions(-)
---
diff --git a/gi/object.cpp b/gi/object.cpp
index 1c3b7c33..f0c41401 100644
--- a/gi/object.cpp
+++ b/gi/object.cpp
@@ -383,8 +383,10 @@ ObjectInstance::prop_getter_impl(JSContext             *cx,
     if (g_param_spec_get_qdata(param, ObjectInstance::custom_property_quark()))
         return true;
 
-    if ((param->flags & G_PARAM_READABLE) == 0)
+    if ((param->flags & G_PARAM_READABLE) == 0) {
+        rval.setUndefined();
         return true;
+    }
 
     gjs_debug_jsprop(GJS_DEBUG_GOBJECT, "Accessing GObject property %s",
                      param->name);
@@ -684,10 +686,7 @@ static bool is_ginterface_property_name(GIInterfaceInfo* info,
         prop_info.reset();
     }
 
-    if (!prop_info)
-        return false;
-
-    return g_property_info_get_flags(prop_info) & G_PARAM_READABLE;
+    return !!prop_info;
 }
 
 bool ObjectPrototype::lazy_define_gobject_property(JSContext* cx,
@@ -799,12 +798,10 @@ is_gobject_property_name(GIObjectInfo *info,
             if (is_ginterface_property_name(iface_info, canonical_name))
                 return true;
         }
-    }
-
-    if (!prop_info)
         return false;
+    }
 
-    return g_property_info_get_flags(prop_info) & G_PARAM_READABLE;
+    return true;
 }
 
 bool ObjectBase::resolve(JSContext* cx, JS::HandleObject obj, JS::HandleId id,
diff --git a/installed-tests/js/testEverythingEncapsulated.js 
b/installed-tests/js/testEverythingEncapsulated.js
index ec8215c1..d463fd75 100644
--- a/installed-tests/js/testEverythingEncapsulated.js
+++ b/installed-tests/js/testEverythingEncapsulated.js
@@ -234,6 +234,16 @@ describe('Introspected GObject', function () {
         expect(obj.name_conflict).toEqual(42);
         expect(obj.name_conflict instanceof Function).toBeFalsy();
     });
+
+    xit('sets write-only properties', function () {
+        expect(obj.int).not.toEqual(0);
+        obj.write_only = true;
+        expect(obj.int).toEqual(0);
+    });
+
+    it('gives undefined for write-only properties', function () {
+        expect(obj.write_only).not.toBeDefined();
+    });
 });
 
 describe('Introspected function length', function () {