Allow serializing context information

Optionally include context information in the
serialization and restore it. This will be useful
for transporting for giving tests complete data
that affects their output.

Some tests included.

1 files changed, 129 insertions, 10 deletions

diff --git a/pango/serializer.c b/pango/serializer.c
index b9c24422..ca92eb21 100644
--- a/pango/serializer.c
+++ b/pango/serializer.c
@@ -23,6 +23,7 @@
 
 #include <pango/pango-layout.h>
 #include <pango/pango-layout-private.h>
+#include <pango/pango-context-private.h>
 #include <pango/pango-enum-types.h>
 
 #include <json-glib/json-glib.h>
@@ -211,8 +212,43 @@ add_tab_array (JsonBuilder   *builder,
   json_builder_end_object (builder);
 }
 
+static void
+add_context (JsonBuilder  *builder,
+             PangoContext *context)
+{
+  json_builder_begin_object (builder);
+
+  /* Note: since we don't create the context when deserializing,
+   * we don't strip out default values here to ensure that the
+   * context gets updated as expected.
+   */
+
+  if (context->set_language)
+    {
+      json_builder_set_member_name (builder, "language");
+      json_builder_add_string_value (builder, pango_language_to_string (context->set_language));
+    }
+
+  json_builder_set_member_name (builder, "base-gravity");
+  add_enum_value (builder, PANGO_TYPE_GRAVITY, context->base_gravity, FALSE);
+
+  json_builder_set_member_name (builder, "gravity-hint");
+  add_enum_value (builder, PANGO_TYPE_GRAVITY_HINT, context->gravity_hint, FALSE);
+
+  json_builder_set_member_name (builder, "direction");
+  add_enum_value (builder, PANGO_TYPE_DIRECTION, context->base_dir, FALSE);
+
+  json_builder_set_member_name (builder, "round-glyph-positions");
+  json_builder_add_boolean_value (builder, context->round_glyph_positions);
+
+  /* FIXME transform */
+
+  json_builder_end_object (builder);
+}
+
 static JsonNode *
-layout_to_json (PangoLayout *layout)
+layout_to_json (PangoLayout               *layout,
+                PangoLayoutSerializeFlags  flags)
 {
   JsonBuilder *builder;
   JsonNode *root;
@@ -221,6 +257,12 @@ layout_to_json (PangoLayout *layout)
 
   json_builder_begin_object (builder);
 
+  if (flags & PANGO_LAYOUT_SERIALIZE_CONTEXT)
+    {
+      json_builder_set_member_name (builder, "context");
+      add_context (builder, layout->context);
+    }
+
   json_builder_set_member_name (builder, "text");
   json_builder_add_string_value (builder, layout->text);
 
@@ -663,16 +705,79 @@ fail:
   return NULL;
 }
 
+static gboolean
+apply_json_to_context (JsonReader    *reader,
+                       PangoContext  *context,
+                       GError       **error)
+{
+  if (json_reader_read_member (reader, "language"))
+    {
+      const char *value;
+      PangoLanguage *language;
+
+      value = json_reader_get_string_value (reader);
+      language = pango_language_from_string (value);
+      pango_context_set_language (context, language);
+    }
+  json_reader_end_member (reader);
+
+  if (json_reader_read_member (reader, "base-gravity"))
+    {
+      PangoGravity gravity = get_enum_value (PANGO_TYPE_GRAVITY,
+                                             json_reader_get_string_value (reader),
+                                             FALSE,
+                                             error);
+      if (gravity == -1)
+        return FALSE;
+
+      pango_context_set_base_gravity (context, gravity);
+    }
+  json_reader_end_member (reader);
+
+  if (json_reader_read_member (reader, "gravity-hint"))
+    {
+      PangoGravityHint gravity_hint = get_enum_value (PANGO_TYPE_GRAVITY_HINT,
+                                                      json_reader_get_string_value (reader),
+                                                      FALSE,
+                                                      error);
+      if (gravity_hint == -1)
+        return FALSE;
+
+      pango_context_set_gravity_hint (context, gravity_hint);
+    }
+  json_reader_end_member (reader);
+
+  if (json_reader_read_member (reader, "base-dir"))
+    {
+      PangoDirection direction = get_enum_value (PANGO_TYPE_DIRECTION,
+                                                 json_reader_get_string_value (reader),
+                                                 FALSE,
+                                                 error);
+      if (direction == -1)
+        return FALSE;
+
+      pango_context_set_base_dir (context, direction);
+    }
+  json_reader_end_member (reader);
+
+  if (json_reader_read_member (reader, "round-glyph-positions"))
+    {
+      pango_context_set_round_glyph_positions (context, json_reader_get_boolean_value (reader));
+    }
+  json_reader_end_member (reader);
+
+  return TRUE;
+}
+
 static PangoLayout *
-json_to_layout (PangoContext *context,
-                JsonNode     *node,
-                GError      **error)
+json_to_layout (PangoContext                 *context,
+                JsonNode                     *node,
+                PangoLayoutDeserializeFlags   flags,
+                GError                      **error)
 {
   JsonReader *reader;
   PangoLayout *layout;
 
-  layout = pango_layout_new (context);
-
   reader = json_reader_new (node);
   if (!json_reader_is_object (reader))
     {
@@ -683,6 +788,18 @@ json_to_layout (PangoContext *context,
       goto fail;
     }
 
+  if (flags & PANGO_LAYOUT_DESERIALIZE_CONTEXT)
+    {
+      if (json_reader_read_member (reader, "context"))
+        {
+          if (!apply_json_to_context (reader, context, error))
+            goto fail;
+        }
+      json_reader_end_member (reader);
+    }
+
+  layout = pango_layout_new (context);
+
   if (json_reader_read_member (reader, "text"))
     pango_layout_set_text (layout, json_reader_get_string_value (reader), -1);
   json_reader_end_member (reader);
@@ -711,7 +828,8 @@ json_to_layout (PangoContext *context,
           g_set_error (error,
                        PANGO_LAYOUT_DESERIALIZE_ERROR,
                        PANGO_LAYOUT_DESERIALIZE_INVALID_VALUE,
-                       "Could not parse \"font\" value: %s",
+                       "Could not parse \"%s\" value: %s",
+                       "font",
                        json_reader_get_string_value (reader));
           goto fail;
         }
@@ -820,7 +938,8 @@ json_to_layout (PangoContext *context,
 
 fail:
   g_object_unref (reader);
-  g_object_unref (layout);
+  if (layout)
+    g_object_unref (layout);
   return NULL;
 }
 
@@ -856,7 +975,7 @@ pango_layout_serialize (PangoLayout               *layout,
 
   g_return_val_if_fail (PANGO_IS_LAYOUT (layout), NULL);
 
-  node = layout_to_json (layout);
+  node = layout_to_json (layout, flags);
 
   generator = json_generator_new ();
   json_generator_set_pretty (generator, TRUE);
@@ -952,7 +1071,7 @@ pango_layout_deserialize (PangoContext                 *context,
     }
 
   node = json_parser_get_root (parser);
-  layout = json_to_layout (context, node, error);
+  layout = json_to_layout (context, node, flags, error);
 
   g_object_unref (parser);