[gtksourceview/wip/chergert/gsv-gtk4: 192/259] bindings: add signal and binding groups




commit 273d576ae11567c5edf3ef882756ca6a0e384944
Author: Christian Hergert <chergert redhat com>
Date:   Sat Aug 29 08:41:56 2020 -0700

    bindings: add signal and binding groups
    
    These can be really handy when dealing with secondary objects like how
    text buffers hang off of text views.

 gtksourceview/gtksourcebindinggroup-private.h |  59 ++
 gtksourceview/gtksourcebindinggroup.c         | 622 +++++++++++++++++++
 gtksourceview/gtksourcesignalgroup-private.h  |  62 ++
 gtksourceview/gtksourcesignalgroup.c          | 849 ++++++++++++++++++++++++++
 gtksourceview/meson.build                     |   2 +
 5 files changed, 1594 insertions(+)
---
diff --git a/gtksourceview/gtksourcebindinggroup-private.h b/gtksourceview/gtksourcebindinggroup-private.h
new file mode 100644
index 00000000..2d2a3453
--- /dev/null
+++ b/gtksourceview/gtksourcebindinggroup-private.h
@@ -0,0 +1,59 @@
+/*
+ * This file is part of GtkSourceView
+ *
+ * Copyright 2015 Christian Hergert <christian hergert me>
+ * Copyright 2015 Garrett Regier <garrettregier gmail com>
+ *
+ * GtkSourceView is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * GtkSourceView is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library; if not, see <http://www.gnu.org/licenses/>.
+ *
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ */
+
+#pragma once
+
+#include <gio/gio.h>
+
+G_BEGIN_DECLS
+
+#define GTK_SOURCE_TYPE_BINDING_GROUP (gtk_source_binding_group_get_type())
+
+G_DECLARE_FINAL_TYPE (GtkSourceBindingGroup, gtk_source_binding_group, GTK_SOURCE, BINDING_GROUP, GObject)
+
+GtkSourceBindingGroup *gtk_source_binding_group_new                (void);
+GObject               *gtk_source_binding_group_get_source         (GtkSourceBindingGroup *self);
+void                   gtk_source_binding_group_set_source         (GtkSourceBindingGroup *self,
+                                                                    gpointer               source);
+void                   gtk_source_binding_group_bind               (GtkSourceBindingGroup *self,
+                                                                    const gchar           *source_property,
+                                                                    gpointer               target,
+                                                                    const gchar           *target_property,
+                                                                    GBindingFlags          flags);
+void                   gtk_source_binding_group_bind_full          (GtkSourceBindingGroup *self,
+                                                                    const gchar           *source_property,
+                                                                    gpointer               target,
+                                                                    const gchar           *target_property,
+                                                                    GBindingFlags          flags,
+                                                                    GBindingTransformFunc  transform_to,
+                                                                    GBindingTransformFunc  transform_from,
+                                                                    gpointer               user_data,
+                                                                    GDestroyNotify         
user_data_destroy);
+void                   gtk_source_binding_group_bind_with_closures (GtkSourceBindingGroup *self,
+                                                                    const gchar           *source_property,
+                                                                    gpointer               target,
+                                                                    const gchar           *target_property,
+                                                                    GBindingFlags          flags,
+                                                                    GClosure              *transform_to,
+                                                                    GClosure              *transform_from);
+
+G_END_DECLS
diff --git a/gtksourceview/gtksourcebindinggroup.c b/gtksourceview/gtksourcebindinggroup.c
new file mode 100644
index 00000000..198fb129
--- /dev/null
+++ b/gtksourceview/gtksourcebindinggroup.c
@@ -0,0 +1,622 @@
+/*
+ * This file is part of GtkSourceView
+ *
+ * Copyright 2015 Christian Hergert <christian hergert me>
+ * Copyright 2015 Garrett Regier <garrettregier gmail com>
+ *
+ * GtkSourceView is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * GtkSourceView is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library; if not, see <http://www.gnu.org/licenses/>.
+ *
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ */
+
+#include "config.h"
+
+#include <glib/gi18n.h>
+
+#include "gtksourcebindinggroup-private.h"
+
+/**
+ * SECTION:gtksourcebindinggroup:
+ * @title: GtkSourceBindingGroup
+ * @short_description: Binding multiple properties as a group
+ *
+ * The #GtkSourceBindingGroup can be used to bind multiple properties
+ * from an object collectively.
+ *
+ * Use the various methods to bind properties from a single source
+ * object to multiple destination objects. Properties can be bound
+ * bidrectionally and are connected when the source object is set
+ * with gtk_source_binding_group_set_source().
+ */
+
+struct _GtkSourceBindingGroup
+{
+       GObject    parent_instance;
+       GObject   *source;
+       GPtrArray *lazy_bindings;
+};
+
+typedef struct
+{
+       GtkSourceBindingGroup *group;
+       const char         *source_property;
+       const char         *target_property;
+       GObject            *target;
+       GBinding           *binding;
+       gpointer            user_data;
+       GDestroyNotify      user_data_destroy;
+       gpointer            transform_to;
+       gpointer            transform_from;
+       GBindingFlags       binding_flags;
+       guint               using_closures : 1;
+} LazyBinding;
+
+G_DEFINE_TYPE (GtkSourceBindingGroup, gtk_source_binding_group, G_TYPE_OBJECT)
+
+enum {
+       PROP_0,
+       PROP_SOURCE,
+       N_PROPS
+};
+
+static GParamSpec *properties [N_PROPS];
+
+/*#define DEBUG_BINDINGS 1*/
+
+#ifdef DEBUG_BINDINGS
+static char *
+_g_flags_to_string (GFlagsClass *flags_class,
+                    guint        value)
+{
+       GString *str = g_string_new (NULL);
+       GFlagsValue *flags_value;
+       gboolean first = TRUE;
+
+       while ((first || value != 0) &&
+              (flags_value = g_flags_get_first_value (flags_class, value)) != NULL)
+       {
+               if (!first)
+                       g_string_append (str, " | ");
+
+               g_string_append (str, flags_value->value_name);
+
+               first = FALSE;
+               value &= ~(flags_value->value);
+               }
+
+       return g_string_free (str, FALSE);
+}
+#endif
+
+static void
+gtk_source_binding_group_connect (GtkSourceBindingGroup *self,
+                                  LazyBinding           *lazy_binding)
+{
+       GBinding *binding;
+
+       g_assert (GTK_SOURCE_IS_BINDING_GROUP (self));
+       g_assert (self->source != NULL);
+       g_assert (lazy_binding != NULL);
+       g_assert (lazy_binding->binding == NULL);
+       g_assert (lazy_binding->target != NULL);
+       g_assert (lazy_binding->target_property != NULL);
+       g_assert (lazy_binding->source_property != NULL);
+
+#ifdef DEBUG_BINDINGS
+       {
+               GFlagsClass *flags_class;
+               g_autofree gchar *flags_str = NULL;
+
+               flags_class = g_type_class_ref (G_TYPE_BINDING_FLAGS);
+               flags_str = _g_flags_to_string (flags_class, lazy_binding->binding_flags);
+
+               g_print ("Binding %s(%p):%s to %s(%p):%s (flags=%s)\n",
+                        G_OBJECT_TYPE_NAME (self->source),
+                        self->source,
+                        lazy_binding->source_property,
+                        G_OBJECT_TYPE_NAME (lazy_binding->target),
+                        lazy_binding->target,
+                        lazy_binding->target_property,
+                        flags_str);
+
+               g_type_class_unref (flags_class);
+       }
+#endif
+
+       if (!lazy_binding->using_closures)
+               binding = g_object_bind_property_full (self->source,
+                                                      lazy_binding->source_property,
+                                                      lazy_binding->target,
+                                                      lazy_binding->target_property,
+                                                      lazy_binding->binding_flags,
+                                                      lazy_binding->transform_to,
+                                                      lazy_binding->transform_from,
+                                                      lazy_binding->user_data,
+                                                      NULL);
+       else
+               binding = g_object_bind_property_with_closures (self->source,
+                                                               lazy_binding->source_property,
+                                                               lazy_binding->target,
+                                                               lazy_binding->target_property,
+                                                               lazy_binding->binding_flags,
+                                                               lazy_binding->transform_to,
+                                                               lazy_binding->transform_from);
+
+       lazy_binding->binding = binding;
+}
+
+static void
+gtk_source_binding_group_disconnect (LazyBinding *lazy_binding)
+{
+       g_assert (lazy_binding != NULL);
+
+       if (lazy_binding->binding != NULL)
+       {
+               g_binding_unbind (lazy_binding->binding);
+               lazy_binding->binding = NULL;
+       }
+}
+
+static void
+gtk_source_binding_group__source_weak_notify (gpointer  data,
+                                              GObject  *where_object_was)
+{
+       GtkSourceBindingGroup *self = data;
+       gsize i;
+
+       g_assert (GTK_SOURCE_IS_BINDING_GROUP (self));
+
+       self->source = NULL;
+
+       for (i = 0; i < self->lazy_bindings->len; i++)
+       {
+               LazyBinding *lazy_binding;
+
+               lazy_binding = g_ptr_array_index (self->lazy_bindings, i);
+               lazy_binding->binding = NULL;
+       }
+}
+
+static void
+gtk_source_binding_group__target_weak_notify (gpointer  data,
+                                              GObject  *where_object_was)
+{
+       GtkSourceBindingGroup *self = data;
+       gsize i;
+
+       g_assert (GTK_SOURCE_IS_BINDING_GROUP (self));
+
+       for (i = 0; i < self->lazy_bindings->len; i++)
+       {
+               LazyBinding *lazy_binding;
+
+               lazy_binding = g_ptr_array_index (self->lazy_bindings, i);
+
+               if (lazy_binding->target == where_object_was)
+               {
+                       lazy_binding->target = NULL;
+                       lazy_binding->binding = NULL;
+
+                       g_ptr_array_remove_index_fast (self->lazy_bindings, i);
+                       break;
+               }
+       }
+}
+
+static void
+lazy_binding_free (gpointer data)
+{
+       LazyBinding *lazy_binding = data;
+
+       if (lazy_binding->target != NULL)
+       {
+               g_object_weak_unref (lazy_binding->target,
+                                    gtk_source_binding_group__target_weak_notify,
+                                    lazy_binding->group);
+               lazy_binding->target = NULL;
+       }
+
+       gtk_source_binding_group_disconnect (lazy_binding);
+
+       lazy_binding->group = NULL;
+       lazy_binding->source_property = NULL;
+       lazy_binding->target_property = NULL;
+
+       if (lazy_binding->user_data_destroy)
+               lazy_binding->user_data_destroy (lazy_binding->user_data);
+
+       if (lazy_binding->using_closures)
+       {
+               g_clear_pointer (&lazy_binding->transform_to, g_closure_unref);
+               g_clear_pointer (&lazy_binding->transform_from, g_closure_unref);
+       }
+
+       g_slice_free (LazyBinding, lazy_binding);
+}
+
+static void
+gtk_source_binding_group_dispose (GObject *object)
+{
+       GtkSourceBindingGroup *self = (GtkSourceBindingGroup *)object;
+
+       g_assert (GTK_SOURCE_IS_BINDING_GROUP (self));
+
+       if (self->source != NULL)
+       {
+               g_object_weak_unref (self->source,
+                                    gtk_source_binding_group__source_weak_notify,
+                                    self);
+               self->source = NULL;
+       }
+
+       if (self->lazy_bindings->len != 0)
+               g_ptr_array_remove_range (self->lazy_bindings, 0, self->lazy_bindings->len);
+
+       G_OBJECT_CLASS (gtk_source_binding_group_parent_class)->dispose (object);
+}
+
+static void
+gtk_source_binding_group_finalize (GObject *object)
+{
+       GtkSourceBindingGroup *self = (GtkSourceBindingGroup *)object;
+
+       g_assert (self->lazy_bindings != NULL);
+       g_assert (self->lazy_bindings->len == 0);
+
+       g_clear_pointer (&self->lazy_bindings, g_ptr_array_unref);
+
+       G_OBJECT_CLASS (gtk_source_binding_group_parent_class)->finalize (object);
+}
+
+static void
+gtk_source_binding_group_get_property (GObject    *object,
+                                       guint       prop_id,
+                                       GValue     *value,
+                                       GParamSpec *pspec)
+{
+       GtkSourceBindingGroup *self = GTK_SOURCE_BINDING_GROUP (object);
+
+       switch (prop_id)
+       {
+       case PROP_SOURCE:
+               g_value_set_object (value, gtk_source_binding_group_get_source (self));
+               break;
+
+       default:
+               G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+       }
+}
+
+static void
+gtk_source_binding_group_set_property (GObject      *object,
+                                       guint         prop_id,
+                                       const GValue *value,
+                                       GParamSpec   *pspec)
+{
+       GtkSourceBindingGroup *self = GTK_SOURCE_BINDING_GROUP (object);
+
+       switch (prop_id)
+       {
+       case PROP_SOURCE:
+               gtk_source_binding_group_set_source (self, g_value_get_object (value));
+               break;
+
+       default:
+               G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+       }
+}
+
+static void
+gtk_source_binding_group_class_init (GtkSourceBindingGroupClass *klass)
+{
+       GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+       object_class->dispose = gtk_source_binding_group_dispose;
+       object_class->finalize = gtk_source_binding_group_finalize;
+       object_class->get_property = gtk_source_binding_group_get_property;
+       object_class->set_property = gtk_source_binding_group_set_property;
+
+       /**
+        * GtkSourceBindingGroup:source:
+        *
+        * The source object used for binding properties.
+        */
+       properties [PROP_SOURCE] =
+               g_param_spec_object ("source",
+                                    "Source",
+                                    "The source GObject used for binding properties.",
+                                    G_TYPE_OBJECT,
+                                    (G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+
+       g_object_class_install_properties (object_class, N_PROPS, properties);
+}
+
+static void
+gtk_source_binding_group_init (GtkSourceBindingGroup *self)
+{
+       self->lazy_bindings = g_ptr_array_new_with_free_func (lazy_binding_free);
+}
+
+/**
+ * gtk_source_binding_group_new:
+ *
+ * Creates a new #GtkSourceBindingGroup.
+ *
+ * Returns: a new #GtkSourceBindingGroup
+ */
+GtkSourceBindingGroup *
+gtk_source_binding_group_new (void)
+{
+       return g_object_new (GTK_SOURCE_TYPE_BINDING_GROUP, NULL);
+}
+
+/**
+ * gtk_source_binding_group_get_source:
+ * @self: the #GtkSourceBindingGroup
+ *
+ * Gets the source object used for binding properties.
+ *
+ * Returns: (transfer none) (nullable): the source object.
+ */
+GObject *
+gtk_source_binding_group_get_source (GtkSourceBindingGroup *self)
+{
+       g_return_val_if_fail (GTK_SOURCE_IS_BINDING_GROUP (self), NULL);
+
+       return self->source;
+}
+
+static gboolean
+gtk_source_binding_group_check_source (GtkSourceBindingGroup *self,
+                                       gpointer               source)
+{
+       for (guint i = 0; i < self->lazy_bindings->len; i++)
+       {
+               LazyBinding *lazy_binding = g_ptr_array_index (self->lazy_bindings, i);
+
+               g_return_val_if_fail (g_object_class_find_property (G_OBJECT_GET_CLASS (source),
+                                                                   lazy_binding->source_property) != NULL,
+                                     FALSE);
+       }
+
+       return TRUE;
+}
+
+/**
+ * gtk_source_binding_group_set_source:
+ * @self: the #GtkSourceBindingGroup
+ * @source: (type GObject) (nullable): the source #GObject
+ *
+ * Sets @source as the source object used for creating property
+ * bindings. If there is already a source object all bindings from it
+ * will be removed.
+ *
+ * Note: All properties that have been bound must exist on @source.
+ */
+void
+gtk_source_binding_group_set_source (GtkSourceBindingGroup *self,
+                                     gpointer               source)
+{
+       g_return_if_fail (GTK_SOURCE_IS_BINDING_GROUP (self));
+       g_return_if_fail (!source || G_IS_OBJECT (source));
+       g_return_if_fail (source != (gpointer)self);
+
+       if (source == (gpointer)self->source)
+               return;
+
+       if (self->source != NULL)
+       {
+               g_object_weak_unref (self->source,
+                                    gtk_source_binding_group__source_weak_notify,
+                                    self);
+               self->source = NULL;
+
+               for (guint i = 0; i < self->lazy_bindings->len; i++)
+               {
+                       LazyBinding *lazy_binding;
+
+                       lazy_binding = g_ptr_array_index (self->lazy_bindings, i);
+                       gtk_source_binding_group_disconnect (lazy_binding);
+               }
+       }
+
+       if (source != NULL && gtk_source_binding_group_check_source (self, source))
+       {
+               self->source = source;
+               g_object_weak_ref (self->source,
+                                  gtk_source_binding_group__source_weak_notify,
+                                  self);
+
+               for (guint i = 0; i < self->lazy_bindings->len; i++)
+               {
+                       LazyBinding *lazy_binding;
+
+                       lazy_binding = g_ptr_array_index (self->lazy_bindings, i);
+                       gtk_source_binding_group_connect (self, lazy_binding);
+               }
+       }
+
+       g_object_notify_by_pspec (G_OBJECT (self), properties [PROP_SOURCE]);
+}
+
+static void
+gtk_source_binding_group_bind_helper (GtkSourceBindingGroup *self,
+                                      const gchar           *source_property,
+                                      gpointer               target,
+                                      const gchar           *target_property,
+                                      GBindingFlags          flags,
+                                      gpointer               transform_to,
+                                      gpointer               transform_from,
+                                      gpointer               user_data,
+                                      GDestroyNotify         user_data_destroy,
+                                      gboolean               using_closures)
+{
+       LazyBinding *lazy_binding;
+
+       g_return_if_fail (GTK_SOURCE_IS_BINDING_GROUP (self));
+       g_return_if_fail (source_property != NULL);
+       g_return_if_fail (self->source == NULL ||
+                         g_object_class_find_property (G_OBJECT_GET_CLASS (self->source),
+                                                       source_property) != NULL);
+       g_return_if_fail (G_IS_OBJECT (target));
+       g_return_if_fail (target_property != NULL);
+       g_return_if_fail (g_object_class_find_property (G_OBJECT_GET_CLASS (target),
+                                                       target_property) != NULL);
+       g_return_if_fail (target != (gpointer)self ||
+                         strcmp (source_property, target_property) != 0);
+
+       lazy_binding = g_slice_new0 (LazyBinding);
+       lazy_binding->group = self;
+       lazy_binding->source_property = g_intern_string (source_property);
+       lazy_binding->target_property = g_intern_string (target_property);
+       lazy_binding->target = target;
+       lazy_binding->binding_flags = flags | G_BINDING_SYNC_CREATE;
+       lazy_binding->user_data = user_data;
+       lazy_binding->user_data_destroy = user_data_destroy;
+       lazy_binding->transform_to = transform_to;
+       lazy_binding->transform_from = transform_from;
+
+       if (using_closures)
+       {
+               lazy_binding->using_closures = TRUE;
+
+               if (transform_to != NULL)
+                       g_closure_sink (g_closure_ref (transform_to));
+
+               if (transform_from != NULL)
+                       g_closure_sink (g_closure_ref (transform_from));
+       }
+
+       g_object_weak_ref (target,
+                          gtk_source_binding_group__target_weak_notify,
+                          self);
+
+       g_ptr_array_add (self->lazy_bindings, lazy_binding);
+
+       if (self->source != NULL)
+               gtk_source_binding_group_connect (self, lazy_binding);
+}
+
+/**
+ * gtk_source_binding_group_bind:
+ * @self: the #GtkSourceBindingGroup
+ * @source_property: the property on the source to bind
+ * @target: (type GObject): the target #GObject
+ * @target_property: the property on @target to bind
+ * @flags: the flags used to create the #GBinding
+ *
+ * Creates a binding between @source_property on the source object
+ * and @target_property on @target. Whenever the @source_property
+ * is changed the @target_property is updated using the same value.
+ * The binding flags #G_BINDING_SYNC_CREATE is automatically specified.
+ *
+ * See: g_object_bind_property().
+ */
+void
+gtk_source_binding_group_bind (GtkSourceBindingGroup *self,
+                               const gchar           *source_property,
+                               gpointer               target,
+                               const gchar           *target_property,
+                               GBindingFlags          flags)
+{
+       gtk_source_binding_group_bind_full (self, source_property,
+                                           target, target_property,
+                                           flags,
+                                           NULL, NULL,
+                                           NULL, NULL);
+}
+
+/**
+ * gtk_source_binding_group_bind_full:
+ * @self: the #GtkSourceBindingGroup
+ * @source_property: the property on the source to bind
+ * @target: (type GObject): the target #GObject
+ * @target_property: the property on @target to bind
+ * @flags: the flags used to create the #GBinding
+ * @transform_to: (scope notified) (nullable): the transformation function
+ *     from the source object to the @target, or %NULL to use the default
+ * @transform_from: (scope notified) (nullable): the transformation function
+ *     from the @target to the source object, or %NULL to use the default
+ * @user_data: custom data to be passed to the transformation
+ *             functions, or %NULL
+ * @user_data_destroy: function to be called when disposing the binding,
+ *     to free the resources used by the transformation functions
+ *
+ * Creates a binding between @source_property on the source object and
+ * @target_property on @target, allowing you to set the transformation
+ * functions to be used by the binding. The binding flags
+ * #G_BINDING_SYNC_CREATE is automatically specified.
+ *
+ * See: g_object_bind_property_full().
+ */
+void
+gtk_source_binding_group_bind_full (GtkSourceBindingGroup *self,
+                                    const gchar           *source_property,
+                                    gpointer               target,
+                                    const gchar           *target_property,
+                                    GBindingFlags          flags,
+                                    GBindingTransformFunc  transform_to,
+                                    GBindingTransformFunc  transform_from,
+                                    gpointer               user_data,
+                                    GDestroyNotify         user_data_destroy)
+{
+       gtk_source_binding_group_bind_helper (self, source_property,
+                                             target, target_property,
+                                             flags,
+                                             transform_to, transform_from,
+                                             user_data, user_data_destroy,
+                                             FALSE);
+}
+
+/**
+ * gtk_source_binding_group_bind_with_closures: (rename-to gtk_source_binding_group_bind_full)
+ * @self: the #GtkSourceBindingGroup
+ * @source_property: the property on the source to bind
+ * @target: (type GObject): the target #GObject
+ * @target_property: the property on @target to bind
+ * @flags: the flags used to create the #GBinding
+ * @transform_to: (nullable): a #GClosure wrapping the
+ *     transformation function from the source object to the @target,
+ *     or %NULL to use the default
+ * @transform_from: (nullable): a #GClosure wrapping the
+ *     transformation function from the @target to the source object,
+ *     or %NULL to use the default
+ *
+ * Creates a binding between @source_property on the source object and
+ * @target_property on @target, allowing you to set the transformation
+ * functions to be used by the binding. The binding flags
+ * #G_BINDING_SYNC_CREATE is automatically specified.
+ *
+ * This function is the language bindings friendly version of
+ * gtk_source_binding_group_bind_property_full(), using #GClosures
+ * instead of function pointers.
+ *
+ * See: g_object_bind_property_with_closures().
+ */
+void
+gtk_source_binding_group_bind_with_closures (GtkSourceBindingGroup *self,
+                                             const gchar           *source_property,
+                                             gpointer               target,
+                                             const gchar           *target_property,
+                                             GBindingFlags          flags,
+                                             GClosure              *transform_to,
+                                             GClosure              *transform_from)
+{
+       gtk_source_binding_group_bind_helper (self, source_property,
+                                             target, target_property,
+                                             flags,
+                                             transform_to, transform_from,
+                                             NULL, NULL,
+                                             TRUE);
+}
diff --git a/gtksourceview/gtksourcesignalgroup-private.h b/gtksourceview/gtksourcesignalgroup-private.h
new file mode 100644
index 00000000..d43cb7c2
--- /dev/null
+++ b/gtksourceview/gtksourcesignalgroup-private.h
@@ -0,0 +1,62 @@
+/* gtk_source-signal-group.h
+ *
+ * Copyright (C) 2015 Christian Hergert <christian hergert me>
+ * Copyright (C) 2015 Garrett Regier <garrettregier gmail com>
+ *
+ * This file is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2.1 of the
+ * License, or (at your option) any later version.
+ *
+ * This file is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ */
+
+#pragma once
+
+#include <glib-object.h>
+
+G_BEGIN_DECLS
+
+#define GTK_SOURCE_TYPE_SIGNAL_GROUP (gtk_source_signal_group_get_type())
+
+G_DECLARE_FINAL_TYPE (GtkSourceSignalGroup, gtk_source_signal_group, GTK_SOURCE, SIGNAL_GROUP, GObject)
+
+GtkSourceSignalGroup *gtk_source_signal_group_new             (GType                 target_type);
+void                  gtk_source_signal_group_set_target      (GtkSourceSignalGroup *self,
+                                                               gpointer              target);
+gpointer              gtk_source_signal_group_get_target      (GtkSourceSignalGroup *self);
+void                  gtk_source_signal_group_block           (GtkSourceSignalGroup *self);
+void                  gtk_source_signal_group_unblock         (GtkSourceSignalGroup *self);
+void                  gtk_source_signal_group_connect_object  (GtkSourceSignalGroup *self,
+                                                               const gchar          *detailed_signal,
+                                                               GCallback             c_handler,
+                                                               gpointer              object,
+                                                               GConnectFlags         flags);
+void                  gtk_source_signal_group_connect_data    (GtkSourceSignalGroup *self,
+                                                               const gchar          *detailed_signal,
+                                                               GCallback             c_handler,
+                                                               gpointer              data,
+                                                               GClosureNotify        notify,
+                                                               GConnectFlags         flags);
+void                  gtk_source_signal_group_connect         (GtkSourceSignalGroup *self,
+                                                               const gchar          *detailed_signal,
+                                                               GCallback             c_handler,
+                                                               gpointer              data);
+void                  gtk_source_signal_group_connect_after   (GtkSourceSignalGroup *self,
+                                                               const gchar          *detailed_signal,
+                                                               GCallback             c_handler,
+                                                               gpointer              data);
+void                  gtk_source_signal_group_connect_swapped (GtkSourceSignalGroup *self,
+                                                               const gchar          *detailed_signal,
+                                                               GCallback             c_handler,
+                                                               gpointer              data);
+
+G_END_DECLS
diff --git a/gtksourceview/gtksourcesignalgroup.c b/gtksourceview/gtksourcesignalgroup.c
new file mode 100644
index 00000000..b517bc09
--- /dev/null
+++ b/gtksourceview/gtksourcesignalgroup.c
@@ -0,0 +1,849 @@
+/* gtk_source-signal-group.c
+ *
+ * Copyright (C) 2015 Christian Hergert <christian hergert me>
+ * Copyright (C) 2015 Garrett Regier <garrettregier gmail com>
+ *
+ * This file is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2.1 of the
+ * License, or (at your option) any later version.
+ *
+ * This file is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ */
+
+#include "config.h"
+
+#include <glib/gi18n.h>
+
+#include "gtksourcesignalgroup-private.h"
+
+/**
+ * SECTION:gtksourcesignalgroup
+ * @title: GtkSourceSignalGroup
+ * @short_description: Manage a collection of signals on a #GObject
+ *
+ * #GtkSourceSignalGroup manages to simplify the process of connecting
+ * many signals to a #GObject as a group. As such there is no API
+ * to disconnect a signal from the group.
+ *
+ * In particular, this allows you to:
+ *
+ *  - Change the target instance, which automatically causes disconnection
+ *    of the signals from the old instance and connecting to the new instance.
+ *  - Block and unblock signals as a group
+ *  - Ensuring that blocked state transfers across target instances.
+ *
+ * One place you might want to use such a structure is with #GtkTextView and
+ * #GtkTextBuffer. Often times, you'll need to connect to many signals on
+ * #GtkTextBuffer from a #GtkTextView subclass. This allows you to create a
+ * signal group during instance construction, simply bind the
+ * #GtkTextView:buffer property to #GtkSourceSignalGroup:target and connect
+ * all the signals you need. When the #GtkTextView:buffer property changes
+ * all of the signals will be transitioned correctly.
+ */
+
+struct _GtkSourceSignalGroup
+{
+  GObject     parent_instance;
+
+  GWeakRef    target_ref;
+  GPtrArray  *handlers;
+  GType       target_type;
+  gsize       block_count;
+
+  guint       has_bound_at_least_once : 1;
+};
+
+struct _GtkSourceSignalGroupClass
+{
+  GObjectClass parent_class;
+
+  void (*bind) (GtkSourceSignalGroup *self,
+                GObject           *target);
+};
+
+typedef struct
+{
+  GtkSourceSignalGroup *group;
+  gulong                handler_id;
+  GClosure             *closure;
+  guint                 signal_id;
+  GQuark                signal_detail;
+  guint                 connect_after : 1;
+} SignalHandler;
+
+G_DEFINE_TYPE (GtkSourceSignalGroup, gtk_source_signal_group, G_TYPE_OBJECT)
+
+enum {
+  PROP_0,
+  PROP_TARGET,
+  PROP_TARGET_TYPE,
+  LAST_PROP
+};
+
+enum {
+  BIND,
+  UNBIND,
+  LAST_SIGNAL
+};
+
+static GParamSpec *properties [LAST_PROP];
+static guint signals [LAST_SIGNAL];
+
+static void
+gtk_source_signal_group_set_target_type (GtkSourceSignalGroup *self,
+                                         GType                 target_type)
+{
+       g_assert (GTK_SOURCE_IS_SIGNAL_GROUP (self));
+       g_assert (g_type_is_a (target_type, G_TYPE_OBJECT));
+
+       self->target_type = target_type;
+
+       /* The class must be created at least once for the signals
+        * to be registered, otherwise g_signal_parse_name() will fail
+        */
+       if (G_TYPE_IS_INTERFACE (target_type))
+       {
+               if (g_type_default_interface_peek (target_type) == NULL)
+                       g_type_default_interface_unref (g_type_default_interface_ref (target_type));
+       }
+       else
+       {
+               if (g_type_class_peek (target_type) == NULL)
+                       g_type_class_unref (g_type_class_ref (target_type));
+       }
+}
+
+static void
+gtk_source_signal_group_gc_handlers (GtkSourceSignalGroup *self)
+{
+       g_assert (GTK_SOURCE_IS_SIGNAL_GROUP (self));
+
+       /* Remove any handlers for which the closures have become invalid. We do
+        * this cleanup lazily to avoid situations where we could have disposal
+        * active on both the signal group and the peer object.
+        */
+
+       for (guint i = self->handlers->len; i > 0; i--)
+       {
+               const SignalHandler *handler = g_ptr_array_index (self->handlers, i - 1);
+
+               g_assert (handler != NULL);
+               g_assert (handler->closure != NULL);
+
+               if (handler->closure->is_invalid)
+               {
+                       g_ptr_array_remove_index (self->handlers, i - 1);
+               }
+       }
+}
+
+static void
+gtk_source_signal_group__target_weak_notify (gpointer  data,
+                                             GObject  *where_object_was)
+{
+       GtkSourceSignalGroup *self = data;
+
+       g_assert (GTK_SOURCE_IS_SIGNAL_GROUP (self));
+       g_assert (where_object_was != NULL);
+
+       g_weak_ref_set (&self->target_ref, NULL);
+
+       for (guint i = 0; i < self->handlers->len; i++)
+       {
+               SignalHandler *handler = g_ptr_array_index (self->handlers, i);
+
+               handler->handler_id = 0;
+       }
+
+       g_signal_emit (self, signals [UNBIND], 0);
+       g_object_notify_by_pspec (G_OBJECT (self), properties [PROP_TARGET]);
+}
+
+static void
+gtk_source_signal_group_bind_handler (GtkSourceSignalGroup *self,
+                                      SignalHandler        *handler,
+                                      GObject              *target)
+{
+       g_assert (self != NULL);
+       g_assert (G_IS_OBJECT (target));
+       g_assert (handler != NULL);
+       g_assert (handler->signal_id != 0);
+       g_assert (handler->closure != NULL);
+       g_assert (handler->closure->is_invalid == 0);
+       g_assert (handler->handler_id == 0);
+
+       handler->handler_id = g_signal_connect_closure_by_id (target,
+                                                             handler->signal_id,
+                                                             handler->signal_detail,
+                                                             handler->closure,
+                                                             handler->connect_after);
+
+       g_assert (handler->handler_id != 0);
+
+       for (guint i = 0; i < self->block_count; i++)
+               g_signal_handler_block (target, handler->handler_id);
+}
+
+static void
+gtk_source_signal_group_bind (GtkSourceSignalGroup *self,
+                              GObject              *target)
+{
+       GObject *hold = NULL;
+
+       g_assert (GTK_SOURCE_IS_SIGNAL_GROUP (self));
+       g_assert (!target || G_IS_OBJECT (target));
+
+       if (target == NULL)
+               return;
+
+       self->has_bound_at_least_once = TRUE;
+
+       hold = g_object_ref (target);
+
+       g_weak_ref_set (&self->target_ref, hold);
+       g_object_weak_ref (hold, gtk_source_signal_group__target_weak_notify, self);
+
+       gtk_source_signal_group_gc_handlers (self);
+
+       for (guint i = 0; i < self->handlers->len; i++)
+       {
+               SignalHandler *handler = g_ptr_array_index (self->handlers, i);
+
+               gtk_source_signal_group_bind_handler (self, handler, hold);
+       }
+
+       g_signal_emit (self, signals [BIND], 0, hold);
+
+       g_clear_object (&hold);
+}
+
+static void
+gtk_source_signal_group_unbind (GtkSourceSignalGroup *self)
+{
+       GObject *target = NULL;
+
+       g_return_if_fail (GTK_SOURCE_IS_SIGNAL_GROUP (self));
+
+       target = g_weak_ref_get (&self->target_ref);
+
+       /* Target may be NULL by this point, as we got notified of its destruction.
+        * However, if we're early enough, we may get a full reference back and can
+        * cleanly disconnect our connections.
+        */
+
+       if (target != NULL)
+       {
+               g_weak_ref_set (&self->target_ref, NULL);
+
+               /* Let go of our weak reference now that we have a full reference
+                * for the life of this function.
+                */
+               g_object_weak_unref (target,
+                                    gtk_source_signal_group__target_weak_notify,
+                                    self);
+       }
+
+       gtk_source_signal_group_gc_handlers (self);
+
+       for (guint i = 0; i < self->handlers->len; i++)
+       {
+               SignalHandler *handler;
+               gulong handler_id;
+
+               handler = g_ptr_array_index (self->handlers, i);
+
+               g_assert (handler != NULL);
+               g_assert (handler->signal_id != 0);
+               g_assert (handler->closure != NULL);
+
+               handler_id = handler->handler_id;
+               handler->handler_id = 0;
+
+               /*
+                * If @target is NULL, we lost a race to cleanup the weak
+                * instance and the signal connections have already been
+                * finalized and therefore nothing to do.
+                */
+
+               if (target != NULL && handler_id != 0)
+                       g_signal_handler_disconnect (target, handler_id);
+       }
+
+       g_signal_emit (self, signals [UNBIND], 0);
+
+       g_clear_object (&target);
+}
+
+static gboolean
+gtk_source_signal_group_check_target_type (GtkSourceSignalGroup *self,
+                                           gpointer              target)
+{
+       if ((target != NULL) &&
+           !g_type_is_a (G_OBJECT_TYPE (target), self->target_type))
+       {
+               g_critical ("Failed to set GtkSourceSignalGroup of target type %s "
+                            "using target %p of type %s",
+                           g_type_name (self->target_type),
+                           target, G_OBJECT_TYPE_NAME (target));
+               return FALSE;
+       }
+
+       return TRUE;
+}
+
+/**
+ * gtk_source_signal_group_block:
+ * @self: the #GtkSourceSignalGroup
+ *
+ * Blocks all signal handlers managed by @self so they will not
+ * be called during any signal emissions. Must be unblocked exactly
+ * the same number of times it has been blocked to become active again.
+ *
+ * This blocked state will be kept across changes of the target instance.
+ *
+ * See: g_signal_handler_block().
+ */
+void
+gtk_source_signal_group_block (GtkSourceSignalGroup *self)
+{
+       GObject *target = NULL;
+
+       g_return_if_fail (GTK_SOURCE_IS_SIGNAL_GROUP (self));
+       g_return_if_fail (self->block_count != G_MAXSIZE);
+
+       self->block_count++;
+
+       target = g_weak_ref_get (&self->target_ref);
+
+       if (target == NULL)
+               return;
+
+       for (guint i = 0; i < self->handlers->len; i++)
+       {
+               const SignalHandler *handler = g_ptr_array_index (self->handlers, i);
+
+               g_assert (handler != NULL);
+               g_assert (handler->signal_id != 0);
+               g_assert (handler->closure != NULL);
+               g_assert (handler->handler_id != 0);
+
+               g_signal_handler_block (target, handler->handler_id);
+       }
+
+       g_clear_object (&target);
+}
+
+/**
+ * gtk_source_signal_group_unblock:
+ * @self: the #GtkSourceSignalGroup
+ *
+ * Unblocks all signal handlers managed by @self so they will be
+ * called again during any signal emissions unless it is blocked
+ * again. Must be unblocked exactly the same number of times it
+ * has been blocked to become active again.
+ *
+ * See: g_signal_handler_unblock().
+ */
+void
+gtk_source_signal_group_unblock (GtkSourceSignalGroup *self)
+{
+       GObject *target = NULL;
+
+       g_return_if_fail (GTK_SOURCE_IS_SIGNAL_GROUP (self));
+       g_return_if_fail (self->block_count != 0);
+
+       self->block_count--;
+
+       target = g_weak_ref_get (&self->target_ref);
+
+       if (target == NULL)
+               return;
+
+       for (guint i = 0; i < self->handlers->len; i++)
+       {
+               const SignalHandler *handler = g_ptr_array_index (self->handlers, i);
+
+               g_assert (handler != NULL);
+               g_assert (handler->signal_id != 0);
+               g_assert (handler->closure != NULL);
+               g_assert (handler->handler_id != 0);
+
+               g_signal_handler_unblock (target, handler->handler_id);
+       }
+
+       g_clear_object (&target);
+}
+
+/**
+ * gtk_source_signal_group_get_target:
+ * @self: the #GtkSourceSignalGroup
+ *
+ * Gets the target instance used when connecting signals.
+ *
+ * Returns: (nullable) (transfer none) (type GObject): The target instance.
+ */
+gpointer
+gtk_source_signal_group_get_target (GtkSourceSignalGroup *self)
+{
+       GObject *target = NULL;
+
+       g_return_val_if_fail (GTK_SOURCE_IS_SIGNAL_GROUP (self), NULL);
+
+       target = g_weak_ref_get (&self->target_ref);
+
+       if (target == NULL || target->ref_count < 2)
+       {
+               /*
+                * It is expected that this is called from a thread that owns a reference to
+                * the target, so we can pass back a borrowed reference. However, to ensure
+                * that we aren't racing in finalization of @target, we must ensure that the
+                * ref_count >= 2 (as our get just incremented by one).
+                */
+               g_clear_object (&target);
+       }
+       else
+       {
+               /* Unref and pass back a borrowed reference. This looks unsafe, but is safe
+                * because of our reference check above, so much as the assertion holds that
+                * the caller obeyed the ownership rules of this class.
+                */
+               g_object_unref (target);
+       }
+
+       return target;
+}
+
+/**
+ * gtk_source_signal_group_set_target:
+ * @self: the #GtkSourceSignalGroup.
+ * @target: (nullable) (type GObject): The target instance used
+ *     when connecting signals.
+ *
+ * Sets the target instance used when connecting signals. Any signal
+ * that has been registered with gtk_source_signal_group_connect_object() or
+ * similar functions will be connected to this object.
+ *
+ * If the target instance was previously set, signals will be
+ * disconnected from that object prior to connecting to @target.
+ */
+void
+gtk_source_signal_group_set_target (GtkSourceSignalGroup *self,
+                                    gpointer              target)
+{
+       GObject *object = NULL;
+
+       g_return_if_fail (GTK_SOURCE_IS_SIGNAL_GROUP (self));
+
+       object = g_weak_ref_get (&self->target_ref);
+
+       if (object == (GObject *)target)
+               goto release;
+
+       if (!gtk_source_signal_group_check_target_type (self, target))
+               goto release;
+
+       /* Only emit unbind if we've ever called bind */
+       if (self->has_bound_at_least_once)
+               gtk_source_signal_group_unbind (self);
+
+       gtk_source_signal_group_bind (self, target);
+
+       g_object_notify_by_pspec (G_OBJECT (self), properties [PROP_TARGET]);
+
+release:
+       g_clear_object (&object);
+}
+
+static void
+signal_handler_free (gpointer data)
+{
+       SignalHandler *handler = data;
+
+       if (handler->closure != NULL)
+               g_closure_invalidate (handler->closure);
+
+       handler->handler_id = 0;
+       handler->signal_id = 0;
+       handler->signal_detail = 0;
+       g_clear_pointer (&handler->closure, g_closure_unref);
+       g_slice_free (SignalHandler, handler);
+}
+
+static void
+gtk_source_signal_group_constructed (GObject *object)
+{
+       GtkSourceSignalGroup *self = (GtkSourceSignalGroup *)object;
+       GObject *target = g_weak_ref_get (&self->target_ref);
+
+       if (!gtk_source_signal_group_check_target_type (self, target))
+               gtk_source_signal_group_set_target (self, NULL);
+
+       G_OBJECT_CLASS (gtk_source_signal_group_parent_class)->constructed (object);
+
+       g_clear_object (&target);
+}
+
+static void
+gtk_source_signal_group_dispose (GObject *object)
+{
+       GtkSourceSignalGroup *self = (GtkSourceSignalGroup *)object;
+
+       gtk_source_signal_group_gc_handlers (self);
+
+       if (self->has_bound_at_least_once)
+               gtk_source_signal_group_unbind (self);
+
+       g_clear_pointer (&self->handlers, g_ptr_array_unref);
+
+       G_OBJECT_CLASS (gtk_source_signal_group_parent_class)->dispose (object);
+}
+
+static void
+gtk_source_signal_group_finalize (GObject *object)
+{
+       GtkSourceSignalGroup *self = (GtkSourceSignalGroup *)object;
+
+       g_weak_ref_clear (&self->target_ref);
+
+       G_OBJECT_CLASS (gtk_source_signal_group_parent_class)->finalize (object);
+}
+
+static void
+gtk_source_signal_group_get_property (GObject    *object,
+                                      guint       prop_id,
+                                      GValue     *value,
+                                      GParamSpec *pspec)
+{
+       GtkSourceSignalGroup *self = GTK_SOURCE_SIGNAL_GROUP (object);
+
+       switch (prop_id)
+       {
+       case PROP_TARGET:
+               g_value_take_object (value, g_weak_ref_get (&self->target_ref));
+               break;
+
+       case PROP_TARGET_TYPE:
+               g_value_set_gtype (value, self->target_type);
+               break;
+
+       default:
+               G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+       }
+}
+
+static void
+gtk_source_signal_group_set_property (GObject      *object,
+                                      guint         prop_id,
+                                      const GValue *value,
+                                      GParamSpec   *pspec)
+{
+       GtkSourceSignalGroup *self = GTK_SOURCE_SIGNAL_GROUP (object);
+
+       switch (prop_id)
+       {
+       case PROP_TARGET:
+               gtk_source_signal_group_set_target (self, g_value_get_object (value));
+               break;
+
+       case PROP_TARGET_TYPE:
+               gtk_source_signal_group_set_target_type (self, g_value_get_gtype (value));
+               break;
+
+       default:
+               G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+       }
+}
+
+static void
+gtk_source_signal_group_class_init (GtkSourceSignalGroupClass *klass)
+{
+       GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+       object_class->constructed = gtk_source_signal_group_constructed;
+       object_class->dispose = gtk_source_signal_group_dispose;
+       object_class->finalize = gtk_source_signal_group_finalize;
+       object_class->get_property = gtk_source_signal_group_get_property;
+       object_class->set_property = gtk_source_signal_group_set_property;
+
+       /**
+        * GtkSourceSignalGroup:target
+        *
+        * The target instance used when connecting signals.
+        */
+       properties [PROP_TARGET] =
+               g_param_spec_object ("target",
+                                    "Target",
+                                    "The target instance used when connecting signals.",
+                                    G_TYPE_OBJECT,
+                                    (G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS));
+
+       /**
+        * GtkSourceSignalGroup:target-type
+        *
+        * The GType of the target property.
+        */
+       properties [PROP_TARGET_TYPE] =
+               g_param_spec_gtype ("target-type",
+                                   "Target Type",
+                                   "The GType of the target property.",
+                                   G_TYPE_OBJECT,
+                                   (G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_STRINGS));
+
+       g_object_class_install_properties (object_class, LAST_PROP, properties);
+
+       /**
+        * GtkSourceSignalGroup::bind:
+        * @self: the #GtkSourceSignalGroup
+        * @instance: a #GObject
+        *
+        * This signal is emitted when the target instance of @self
+        * is set to a new #GObject.
+        *
+        * This signal will only be emitted if the target of @self is non-%NULL.
+        */
+       signals [BIND] =
+               g_signal_new ("bind",
+                             G_TYPE_FROM_CLASS (klass),
+                             G_SIGNAL_RUN_LAST,
+                             0,
+                             NULL, NULL, NULL,
+                             G_TYPE_NONE,
+                             1,
+                             G_TYPE_OBJECT);
+
+       /**
+        * GtkSourceSignalGroup::unbind:
+        * @self: a #GtkSourceSignalGroup
+        *
+        * This signal is emitted when the target instance of @self
+        * is set to a new #GObject.
+        *
+        * This signal will only be emitted if the previous target
+        * of @self is non-%NULL.
+        */
+       signals [UNBIND] =
+               g_signal_new ("unbind",
+                             G_TYPE_FROM_CLASS (klass),
+                             G_SIGNAL_RUN_LAST,
+                             0,
+                             NULL, NULL, NULL,
+                             G_TYPE_NONE,
+                             0);
+}
+
+static void
+gtk_source_signal_group_init (GtkSourceSignalGroup *self)
+{
+       self->handlers = g_ptr_array_new_with_free_func (signal_handler_free);
+       self->target_type = G_TYPE_OBJECT;
+}
+
+/**
+ * gtk_source_signal_group_new:
+ * @target_type: the #GType of the target instance.
+ *
+ * Creates a new #GtkSourceSignalGroup for target instances of @target_type.
+ *
+ * Returns: a new #GtkSourceSignalGroup
+ */
+GtkSourceSignalGroup *
+gtk_source_signal_group_new (GType target_type)
+{
+       g_return_val_if_fail (g_type_is_a (target_type, G_TYPE_OBJECT), NULL);
+
+       return g_object_new (GTK_SOURCE_TYPE_SIGNAL_GROUP,
+                            "target-type", target_type,
+                            NULL);
+}
+
+static void
+gtk_source_signal_group_connect_full (GtkSourceSignalGroup *self,
+                                      const gchar          *detailed_signal,
+                                      GCallback             callback,
+                                      gpointer              data,
+                                      GClosureNotify        notify,
+                                      GConnectFlags         flags,
+                                      gboolean              is_object)
+{
+       GObject *target = NULL;
+       SignalHandler *handler;
+       GClosure *closure;
+       guint signal_id;
+       GQuark signal_detail;
+
+       g_return_if_fail (GTK_SOURCE_IS_SIGNAL_GROUP (self));
+       g_return_if_fail (detailed_signal != NULL);
+       g_return_if_fail (g_signal_parse_name (detailed_signal, self->target_type,
+                                              &signal_id, &signal_detail, TRUE) != 0);
+       g_return_if_fail (callback != NULL);
+       g_return_if_fail (!is_object || G_IS_OBJECT (data));
+
+       if ((flags & G_CONNECT_SWAPPED) != 0)
+               closure = g_cclosure_new_swap (callback, data, notify);
+       else
+               closure = g_cclosure_new (callback, data, notify);
+
+       handler = g_slice_new0 (SignalHandler);
+       handler->group = self;
+       handler->signal_id = signal_id;
+       handler->signal_detail = signal_detail;
+       handler->closure = g_closure_ref (closure);
+       handler->connect_after = ((flags & G_CONNECT_AFTER) != 0);
+
+       g_closure_sink (closure);
+
+       if (is_object)
+       {
+               /* Set closure->is_invalid when data is disposed. We only track this to avoid
+                * reconnecting in the future. However, we do a round of cleanup when ever we
+                * connect a new object or the target changes to GC the old handlers.
+                */
+               g_object_watch_closure (data, closure);
+       }
+
+       g_ptr_array_add (self->handlers, handler);
+
+       target = g_weak_ref_get (&self->target_ref);
+       if (target != NULL)
+               gtk_source_signal_group_bind_handler (self, handler, target);
+
+       /* Lazily remove any old handlers on connect */
+       gtk_source_signal_group_gc_handlers (self);
+
+       g_clear_object (&target);
+}
+
+/**
+ * gtk_source_signal_group_connect_object: (skip)
+ * @self: a #GtkSourceSignalGroup
+ * @detailed_signal: a string of the form "signal-name::detail"
+ * @c_handler: (scope notified): the #GCallback to connect
+ * @object: the #GObject to pass as data to @callback calls
+ *
+ * Connects @callback to the signal @detailed_signal
+ * on the target object of @self.
+ *
+ * Ensures that the @object stays alive during the call to @callback
+ * by temporarily adding a reference count. When the @object is destroyed
+ * the signal handler will automatically be removed.
+ *
+ * See: g_signal_connect_object().
+ */
+void
+gtk_source_signal_group_connect_object (GtkSourceSignalGroup *self,
+                                        const gchar          *detailed_signal,
+                                        GCallback             c_handler,
+                                        gpointer              object,
+                                        GConnectFlags         flags)
+{
+       g_return_if_fail (G_IS_OBJECT (object));
+
+       gtk_source_signal_group_connect_full (self, detailed_signal, c_handler,
+                                             object, NULL, flags, TRUE);
+}
+
+/**
+ * gtk_source_signal_group_connect_data:
+ * @self: a #GtkSourceSignalGroup
+ * @detailed_signal: a string of the form "signal-name::detail"
+ * @c_handler: (scope notified) (closure data) (destroy notify): the #GCallback to connect
+ * @data: the data to pass to @callback calls
+ * @notify: function to be called when disposing of @self
+ * @flags: the flags used to create the signal connection
+ *
+ * Connects @callback to the signal @detailed_signal
+ * on the target instance of @self.
+ *
+ * See: g_signal_connect_data().
+ */
+void
+gtk_source_signal_group_connect_data (GtkSourceSignalGroup *self,
+                                      const gchar          *detailed_signal,
+                                      GCallback             c_handler,
+                                      gpointer              data,
+                                      GClosureNotify        notify,
+                                      GConnectFlags         flags)
+{
+       gtk_source_signal_group_connect_full (self, detailed_signal, c_handler,
+                                             data, notify, flags, FALSE);
+}
+
+/**
+ * gtk_source_signal_group_connect: (skip)
+ * @self: a #GtkSourceSignalGroup
+ * @detailed_signal: a string of the form "signal-name::detail"
+ * @c_handler: (scope notified): the #GCallback to connect
+ * @data: the data to pass to @callback calls
+ *
+ * Connects @callback to the signal @detailed_signal
+ * on the target instance of @self.
+ *
+ * See: g_signal_connect().
+ */
+void
+gtk_source_signal_group_connect (GtkSourceSignalGroup *self,
+                                 const gchar          *detailed_signal,
+                                 GCallback             c_handler,
+                                 gpointer              data)
+{
+       gtk_source_signal_group_connect_full (self, detailed_signal, c_handler, data, NULL,
+                                             0, FALSE);
+}
+
+/**
+ * gtk_source_signal_group_connect_after: (skip)
+ * @self: a #GtkSourceSignalGroup
+ * @detailed_signal: a string of the form "signal-name::detail"
+ * @c_handler: (scope notified): the #GCallback to connect
+ * @data: the data to pass to @callback calls
+ *
+ * Connects @callback to the signal @detailed_signal
+ * on the target instance of @self.
+ *
+ * The @callback will be called after the default handler of the signal.
+ *
+ * See: g_signal_connect_after().
+ */
+void
+gtk_source_signal_group_connect_after (GtkSourceSignalGroup *self,
+                                       const gchar          *detailed_signal,
+                                       GCallback             c_handler,
+                                       gpointer              data)
+{
+       gtk_source_signal_group_connect_full (self, detailed_signal, c_handler,
+                                             data, NULL, G_CONNECT_AFTER, FALSE);
+}
+
+/**
+ * gtk_source_signal_group_connect_swapped:
+ * @self: a #GtkSourceSignalGroup
+ * @detailed_signal: a string of the form "signal-name::detail"
+ * @c_handler: (scope async): the #GCallback to connect
+ * @data: the data to pass to @callback calls
+ *
+ * Connects @callback to the signal @detailed_signal
+ * on the target instance of @self.
+ *
+ * The instance on which the signal is emitted and @data
+ * will be swapped when calling @callback.
+ *
+ * See: g_signal_connect_swapped().
+ */
+void
+gtk_source_signal_group_connect_swapped (GtkSourceSignalGroup *self,
+                                         const gchar          *detailed_signal,
+                                         GCallback             c_handler,
+                                         gpointer              data)
+{
+       gtk_source_signal_group_connect_full (self, detailed_signal, c_handler, data, NULL,
+                                             G_CONNECT_SWAPPED, FALSE);
+}
diff --git a/gtksourceview/meson.build b/gtksourceview/meson.build
index e0e71c77..9d3d26ba 100644
--- a/gtksourceview/meson.build
+++ b/gtksourceview/meson.build
@@ -85,6 +85,7 @@ core_public_c = files([
 ])
 
 core_private_c = files([
+  'gtksourcebindinggroup.c',
   'gtksourcebufferinputstream.c',
   'gtksourcebufferinternal.c',
   'gtksourcebufferoutputstream.c',
@@ -99,6 +100,7 @@ core_private_c = files([
   'gtksourcemarkssequence.c',
   'gtksourcepixbufhelper.c',
   'gtksourceregex.c',
+  'gtksourcesignalgroup.c',
 ])
 
 core_c_args = [


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