Handle property name collisions

Properties cannot have the same name as signals, methods, and virtual
functions, as they will break various language bindings.

Since listing this requirement only in the documentation has been
insufficient, we should emit a warning, and hope that library developers
will pay attention to it.

Fixes: #386

1 files changed, 41 insertions, 0 deletions

diff --git a/giscanner/introspectablepass.py b/giscanner/introspectablepass.py
index d09b12a4..0f51ada4 100644
--- a/giscanner/introspectablepass.py
+++ b/giscanner/introspectablepass.py
@@ -40,6 +40,7 @@ class IntrospectablePass(object):
         self._namespace.walk(self._introspectable_property_analysis)
         self._namespace.walk(self._introspectable_pass3)
         self._namespace.walk(self._remove_non_reachable_backcompat_copies)
+        self._namespace.walk(self._introspectable_symbol_collisions)
 
     def _parameter_warning(self, parent, param, text, position=None):
         # Suppress VFunctions and Callbacks warnings for now
@@ -260,3 +261,43 @@ class IntrospectablePass(object):
             if not obj.introspectable:
                 obj.internal_skipped = True
         return True
+
+    def _property_warning(self, parent, prop, text, position=None):
+        context = "property %s:%s: " % (parent.name, prop.name, )
+        message.warn_node(parent, context + text, positions=position)
+
+    def _property_signal_collision(self, obj, prop):
+        for s in obj.signals:
+            if s.skip or not s.introspectable:
+                continue
+            if s.name.replace('-', '_') == prop.name.replace('-', '_'):
+                self._property_warning(obj, prop, "Properties cannot have the same name as signals")
+        return False
+
+    def _property_method_collision(self, obj, prop):
+        for m in obj.methods:
+            if m.skip or not m.introspectable:
+                continue
+            if m.name == prop.name.replace('-', '_'):
+                self._property_warning(obj, prop, "Properties cannot have the same name as methods")
+        return False
+
+    def _property_vfunc_collision(self, obj, prop):
+        for vfunc in obj.virtual_methods:
+            if vfunc.skip or not vfunc.introspectable:
+                continue
+            if vfunc.name == prop.name.replace('-', '_'):
+                self._property_warning(obj, prop, "Properties cannot have the same name as virtual methods")
+        return False
+
+    def _introspectable_symbol_collisions(self, obj, stack):
+        if obj.skip:
+            return False
+        if isinstance(obj, (ast.Class, ast.Interface)):
+            for prop in obj.properties:
+                if prop.skip or not prop.introspectable:
+                    continue
+                self._property_signal_collision(obj, prop)
+                self._property_method_collision(obj, prop)
+                self._property_vfunc_collision(obj, prop)
+        return True