Make "hunting for Scintilla" a little more robust

gistfile1.diff

diff --git a/src/document.c b/src/document.c
index 8a57d93..edaed0d 100644
--- a/src/document.c
+++ b/src/document.c
@@ -226,16 +226,8 @@ GeanyDocument *document_find_by_filename(const gchar *utf8_filename)
 /* returns the document which has sci, or NULL. */
 GeanyDocument *document_find_by_sci(ScintillaObject *sci)
 {
-	guint i;
-
-	g_return_val_if_fail(sci != NULL, NULL);
-
-	for (i = 0; i < documents_array->len; i++)
-	{
-		if (documents[i]->is_valid && documents[i]->editor->sci == sci)
-			return documents[i];
-	}
-	return NULL;
+	g_return_val_if_fail(IS_SCINTILLA(sci), NULL);
+	return g_object_get_data(G_OBJECT(sci), "geany-document");
 }
 
 
@@ -305,6 +297,16 @@ gint document_get_notebook_page(GeanyDocument *doc)
 }
 
 
+/* Check if the object is not only a Scintilla but also has our special
+ * "geany-document" tag set in editor_create_widget(). This prevents finding
+ * other Scintilla widgets that plugin's might have sneakily packed into the
+ * widget tree we search through to find our Scintilla. */
+static inline gboolean is_geany_scintilla(gpointer obj)
+{
+	return IS_SCINTILLA(obj) && (g_object_get_data(obj, "geany-document") != NULL);
+}
+
+
 /*
  * Recursively searches a containers children until it finds a
  * Scintilla widget, or NULL if one was not found.
@@ -319,7 +321,7 @@ static ScintillaObject *locate_sci_in_container(GtkWidget *container)
 	children = gtk_container_get_children(GTK_CONTAINER(container));
 	for (iter = children; iter != NULL; iter = g_list_next(iter))
 	{
-		if (IS_SCINTILLA(iter->data))
+		if (is_geany_scintilla(iter->data))
 		{
 			sci = SCINTILLA(iter->data);
 			break;
@@ -327,7 +329,7 @@ static ScintillaObject *locate_sci_in_container(GtkWidget *container)
 		else if (GTK_IS_CONTAINER(iter->data))
 		{
 			sci = locate_sci_in_container(iter->data);
-			if (IS_SCINTILLA(sci))
+			if (is_geany_scintilla(sci))
 				break;
 			sci = NULL;
 		}
diff --git a/src/editor.c b/src/editor.c
index fc04ac6..a9c433e 100644
--- a/src/editor.c
+++ b/src/editor.c
@@ -4831,6 +4831,9 @@ ScintillaObject *editor_create_widget(GeanyEditor *editor)
 		editor->indent_width = old_indent_width;
 		editor->sci = old;
 	}
+
+	g_object_set_data(G_OBJECT(sci), "geany-document", editor->document);
+
 	return sci;
 }