[gtk/wip/ebassi/constraint-layout] Return the list of constraints added via VFL description

[Emmanuele Bassi <ebassi src gnome org>]

commit d6fa7da1badb9e76747b0f699fb9a40b7a595600
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Sun Jun 30 10:36:33 2019 +0100

    Return the list of constraints added via VFL description
    
    Otherwise it's impossible to remove them.

 gtk/gtkconstraintlayout.c | 35 ++++++++++++++++++++---------------
 gtk/gtkconstraintlayout.h |  4 ++--
 2 files changed, 22 insertions(+), 17 deletions(-)
---
diff --git a/gtk/gtkconstraintlayout.c b/gtk/gtkconstraintlayout.c
index e90ac25cc3..82db0f210c 100644
--- a/gtk/gtkconstraintlayout.c
+++ b/gtk/gtkconstraintlayout.c
@@ -1719,9 +1719,10 @@ attribute_from_name (const char *name)
  *   [button1(==button2.height)]
  * ]|
  *
- * Returns: %TRUE if the constraints were added to the layout
+ * Returns: (transfer container) (element-type GtkConstraint): the list of
+ *   #GtkConstraints that were added to the layout
  */
-gboolean
+GList *
 gtk_constraint_layout_add_constraints_from_descriptionv (GtkConstraintLayout *layout,
                                                          const char * const   lines[],
                                                          gsize                n_lines,
@@ -1731,11 +1732,12 @@ gtk_constraint_layout_add_constraints_from_descriptionv (GtkConstraintLayout *la
                                                          GError             **error)
 {
   GtkConstraintVflParser *parser;
+  GList *res = NULL;
 
-  g_return_val_if_fail (GTK_IS_CONSTRAINT_LAYOUT (layout), FALSE);
-  g_return_val_if_fail (lines != NULL, FALSE);
-  g_return_val_if_fail (views != NULL, FALSE);
-  g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
+  g_return_val_if_fail (GTK_IS_CONSTRAINT_LAYOUT (layout), NULL);
+  g_return_val_if_fail (lines != NULL, NULL);
+  g_return_val_if_fail (views != NULL, NULL);
+  g_return_val_if_fail (error == NULL || *error == NULL, NULL);
 
   parser = gtk_constraint_vfl_parser_new ();
   gtk_constraint_vfl_parser_set_default_spacing (parser, hspacing, vspacing);
@@ -1776,7 +1778,7 @@ gtk_constraint_layout_add_constraints_from_descriptionv (GtkConstraintLayout *la
           g_free (squiggly);
           g_error_free (internal_error);
           gtk_constraint_vfl_parser_free (parser);
-          return FALSE;
+          return res;
         }
 
       int n_constraints = 0;
@@ -1810,6 +1812,8 @@ gtk_constraint_layout_add_constraints_from_descriptionv (GtkConstraintLayout *la
 
           layout_add_constraint (layout, constraint);
           g_hash_table_add (layout->constraints, constraint);
+
+          res = g_list_prepend (res, constraint);
         }
 
       g_free (constraints);
@@ -1817,7 +1821,7 @@ gtk_constraint_layout_add_constraints_from_descriptionv (GtkConstraintLayout *la
 
   gtk_constraint_vfl_parser_free (parser);
 
-  return TRUE;
+  return res;
 }
 
 /**
@@ -1840,9 +1844,10 @@ gtk_constraint_layout_add_constraints_from_descriptionv (GtkConstraintLayout *la
  * gtk_constraint_layout_add_constraints_from_descriptionv(), using
  * variadic arguments to populate the view/target map.
  *
- * Returns: %TRUE if the constraints were added to the layout
+ * Returns: (transfer container) (element-type GtkConstraint): the list of
+ *   #GtkConstraints that were added to the layout
  */
-gboolean
+GList *
 gtk_constraint_layout_add_constraints_from_description (GtkConstraintLayout *layout,
                                                         const char * const   lines[],
                                                         gsize                n_lines,
@@ -1855,13 +1860,13 @@ gtk_constraint_layout_add_constraints_from_description (GtkConstraintLayout *lay
   GtkConstraintVflParser *parser;
   GHashTable *views;
   const char *view;
-  gboolean res;
+  GList *res;
   va_list args;
 
-  g_return_val_if_fail (GTK_IS_CONSTRAINT_LAYOUT (layout), FALSE);
-  g_return_val_if_fail (lines != NULL, FALSE);
-  g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
-  g_return_val_if_fail (first_view != NULL, FALSE);
+  g_return_val_if_fail (GTK_IS_CONSTRAINT_LAYOUT (layout), NULL);
+  g_return_val_if_fail (lines != NULL, NULL);
+  g_return_val_if_fail (error == NULL || *error == NULL, NULL);
+  g_return_val_if_fail (first_view != NULL, NULL);
 
   parser = gtk_constraint_vfl_parser_new ();
   gtk_constraint_vfl_parser_set_default_spacing (parser, hspacing, vspacing);
diff --git a/gtk/gtkconstraintlayout.h b/gtk/gtkconstraintlayout.h
index 5294ec74a4..52a79ac93f 100644
--- a/gtk/gtkconstraintlayout.h
+++ b/gtk/gtkconstraintlayout.h
@@ -79,7 +79,7 @@ GDK_AVAILABLE_IN_ALL
 void                    gtk_constraint_layout_remove_all_constraints            (GtkConstraintLayout 
*manager);
 
 GDK_AVAILABLE_IN_ALL
-gboolean                gtk_constraint_layout_add_constraints_from_description  (GtkConstraintLayout 
*manager,
+GList *                 gtk_constraint_layout_add_constraints_from_description  (GtkConstraintLayout 
*manager,
                                                                                  const char * const   
lines[],
                                                                                  gsize                
n_lines,
                                                                                  int                  
hspacing,
@@ -88,7 +88,7 @@ gboolean                gtk_constraint_layout_add_constraints_from_description
                                                                                  const char          
*first_view,
                                                                                  ...) G_GNUC_NULL_TERMINATED;
 GDK_AVAILABLE_IN_ALL
-gboolean                gtk_constraint_layout_add_constraints_from_descriptionv (GtkConstraintLayout 
*manager,
+GList *                 gtk_constraint_layout_add_constraints_from_descriptionv (GtkConstraintLayout 
*manager,
                                                                                  const char * const   
lines[],
                                                                                  gsize                
n_lines,
                                                                                  int                  
hspacing,