[vala/wip/tintou/dbus-proxy-set-interface-info] gdbus: Use GDBusProxy API to set `g-interface-info` at initialization time

[Rico Tzschichholz <ricotz src gnome org>]

commit 25f93c2822095743f9c8d090e28c4610a324bf0f
Author: Corentin Noël <corentin elementary io>
Date:   Fri Apr 3 12:53:27 2020 +0200

    gdbus: Use GDBusProxy API to set `g-interface-info` at initialization time
    
    This allows GDBusProxy subclasses to have the g-interface-info assigned
    even when the class hasn't been created by Vala itself.
    
    Keep obsolete setting of 'vala-dbus-interface-info' to preserve backwards
    compatibility.

 codegen/valagdbusclientmodule.vala | 26 ++++++++--------
 tests/Makefile.am                  |  1 +
 tests/dbus/interface-info.test     | 62 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 75 insertions(+), 14 deletions(-)
---
diff --git a/codegen/valagdbusclientmodule.vala b/codegen/valagdbusclientmodule.vala
index 12a7693d2..2327a09aa 100644
--- a/codegen/valagdbusclientmodule.vala
+++ b/codegen/valagdbusclientmodule.vala
@@ -236,6 +236,17 @@ public class Vala.GDBusClientModule : GDBusModule {
                var proxy_instance_init = new CCodeFunction (lower_cname + "_init", "void");
                proxy_instance_init.add_parameter (new CCodeParameter ("self", cname + "*"));
                proxy_instance_init.modifiers = CCodeModifiers.STATIC;
+               push_function (proxy_instance_init);
+
+               // TODO Replaces setting of "vala-dbus-interface-info"
+               var dbus_proxy_cast = new CCodeFunctionCall (new CCodeIdentifier ("G_DBUS_PROXY"));
+               dbus_proxy_cast.add_argument (new CCodeIdentifier ("self"));
+               var set_interface_info = new CCodeFunctionCall (new CCodeIdentifier 
("g_dbus_proxy_set_interface_info"));
+               set_interface_info.add_argument (dbus_proxy_cast);
+               set_interface_info.add_argument (new CCodeCastExpression (new CCodeUnaryExpression 
(CCodeUnaryOperator.ADDRESS_OF, get_interface_info (iface)), "GDBusInterfaceInfo *"));
+               ccode.add_expression (set_interface_info);
+
+               pop_function ();
                cfile.add_function (proxy_instance_init);
 
                generate_proxy_interface_init (iface, iface);
@@ -257,7 +268,6 @@ public class Vala.GDBusClientModule : GDBusModule {
 
                CCodeExpression proxy_type;
                CCodeExpression dbus_iface_name;
-               CCodeExpression dbus_iface_info;
 
                var object_type = type_arg as ObjectType;
                if (object_type != null) {
@@ -292,15 +302,6 @@ public class Vala.GDBusClientModule : GDBusModule {
                        dbus_iface_name = get_qdata;
                }
 
-               var quark = new CCodeFunctionCall (new CCodeIdentifier ("g_quark_from_static_string"));
-               quark.add_argument (new CCodeConstant ("\"vala-dbus-interface-info\""));
-
-               var get_qdata = new CCodeFunctionCall (new CCodeIdentifier ("g_type_get_qdata"));
-               get_qdata.add_argument (get_type_id_expression (type_arg));
-               get_qdata.add_argument (quark);
-
-               dbus_iface_info = get_qdata;
-
                if (bus_get_proxy_async || conn_get_proxy_async) {
                        if (ma.member_name == "end" && ma.inner.symbol_reference == ma.symbol_reference) {
                                // method can fail
@@ -397,10 +398,6 @@ public class Vala.GDBusClientModule : GDBusModule {
                ccall.add_argument (get_cvalue (object_path));
                ccall.add_argument (new CCodeConstant ("\"g-interface-name\""));
                ccall.add_argument (dbus_iface_name);
-               if (dbus_iface_info != null) {
-                       ccall.add_argument (new CCodeConstant ("\"g-interface-info\""));
-                       ccall.add_argument (dbus_iface_info);
-               }
                ccall.add_argument (new CCodeConstant ("NULL"));
 
                if (bus_get_proxy_async || conn_get_proxy_async) {
@@ -1212,6 +1209,7 @@ public class Vala.GDBusClientModule : GDBusModule {
 
                block.add_statement (new CCodeExpressionStatement (set_qdata));
 
+               // TODO Replaced by g_dbus_proxy_set_interface_info() call in *_init
                quark = new CCodeFunctionCall (new CCodeIdentifier ("g_quark_from_static_string"));
                quark.add_argument (new CCodeConstant ("\"vala-dbus-interface-info\""));
 
diff --git a/tests/Makefile.am b/tests/Makefile.am
index cca6a2927..88aaac40a 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -589,6 +589,7 @@ TESTS = \
        dbus/bug783002.test \
        dbus/bug792277.vala \
        dbus/rawvariants.test \
+       dbus/interface-info.test \
        gir/bug651773.test \
        gir/bug667751.test \
        gir/bug742012.test \
diff --git a/tests/dbus/interface-info.test b/tests/dbus/interface-info.test
new file mode 100644
index 000000000..e4235df59
--- /dev/null
+++ b/tests/dbus/interface-info.test
@@ -0,0 +1,62 @@
+Packages: gio-2.0
+D-Bus
+
+Program: client
+
+[DBus (name = "org.example.Test")]
+interface Test : Object {
+       [DBus (name = "Baz")]
+       public signal void bar (string j);
+}
+
+MainLoop main_loop;
+
+void main () {
+       // client
+       Test test = Bus.get_proxy_sync (BusType.SESSION, "org.example.Test", "/org/example/test");
+
+       unowned DBusProxy proxy = (DBusProxy) test;
+       unowned DBusInterfaceInfo? iface_info = proxy.get_interface_info ();
+       assert (iface_info != null);
+       assert (iface_info.signals != null);
+       assert (iface_info.signals[0] != null);
+       assert (iface_info.signals[0].name == "Baz");
+       assert (iface_info.signals[0].args != null);
+       assert (iface_info.signals[0].args[0] != null);
+       assert (iface_info.signals[0].args[0].signature == "s");
+
+       assert (iface_info == (DBusInterfaceInfo?) typeof (Test).get_qdata (Quark.from_string 
("vala-dbus-interface-info")));
+}
+
+Program: server
+
+[DBus (name = "org.example.Test")]
+class Test : Object {
+       public signal void foo (int i);
+}
+
+MainLoop main_loop;
+
+void client_exit (Pid pid, int status) {
+       // client finished, terminate server
+       assert (status == 0);
+       main_loop.quit ();
+}
+
+void main () {
+       var conn = Bus.get_sync (BusType.SESSION);
+       conn.register_object ("/org/example/test", new Test ());
+
+       // try to register service in session bus
+       var request_result = conn.call_sync ("org.freedesktop.DBus", "/org/freedesktop/DBus", 
"org.freedesktop.DBus", "RequestName",
+                                             new Variant ("(su)", "org.example.Test", 0x4), null, 0, -1);
+       assert ((uint) request_result.get_child_value (0) == 1);
+
+       // server ready, spawn client
+       Pid client_pid;
+       Process.spawn_async (null, { "dbus_interface_info_client" }, null, SpawnFlags.DO_NOT_REAP_CHILD, 
null, out client_pid);
+       ChildWatch.add (client_pid, client_exit);
+
+       main_loop = new MainLoop ();
+       main_loop.run ();
+}