[gxml/gxml-0.8] TwDocument.save_to() now makes a backup by default

[Daniel Espinosa Ortiz <despinosa src gnome org>]

commit 9230874cb0afd736a7909622c5622365d18cea2a
Author: Daniel Espinosa <esodan gmail com>
Date:   Tue Jan 12 14:40:32 2016 -0600

    TwDocument.save_to() now makes a backup by default
    
    * Added asserts to Xmlx methods

 gxml/TwDocument.vala     |   29 +++++++++++++++++++++++-
 gxml/xlibxml.c           |   16 +++++++++++++
 gxml/xlibxml.h           |    3 ++
 test/TwDocumentTest.vala |   56 ++++++++++++++++++++++++++++++++++++++++-----
 vapi/xlibxml-1.0.vapi    |    2 +
 5 files changed, 98 insertions(+), 8 deletions(-)
---
diff --git a/gxml/TwDocument.vala b/gxml/TwDocument.vala
index 5fe699e..987bf93 100644
--- a/gxml/TwDocument.vala
+++ b/gxml/TwDocument.vala
@@ -31,6 +31,7 @@ using Xml;
 public class GXml.TwDocument : GXml.TwNode, GXml.Document
 {
   GXml.Element _root = null;
+  Xml.Buffer _buffer;
   construct {
     _name = "#document";
   }
@@ -117,8 +118,34 @@ public class GXml.TwDocument : GXml.TwNode, GXml.Document
   }
   public bool save_to (GLib.File f, GLib.Cancellable? cancellable = null)
   {
-    var tw = new Xml.TextWriter.filename (f.get_path ());
+    file = f;
+    var buf = new Xml.Buffer ();
+    var tw = Xmlx.new_text_writer_memory (buf, 0);
+    GLib.Test.message ("Writing down to buffer");
     write_document (tw);
+    GLib.Test.message ("Writing down to file");
+    GLib.Test.message ("TextWriter buffer:\n"+buf.content ());
+    var s = new GLib.StringBuilder ();
+    s.append (buf.content ());
+    try {
+      GLib.Test.message ("Writing down to file: Creating input stream");
+      var b = new GLib.MemoryInputStream.from_data (s.data, null);
+      GLib.OutputStream ostream;
+      if (file.query_exists ()) {
+      GLib.Test.message ("Writing down to file: Replacing with backup");
+        ostream = file.replace (null, true, GLib.FileCreateFlags.NONE, cancellable);
+        ostream.splice (b, GLib.OutputStreamSpliceFlags.NONE);
+        ostream.close ();
+      } else {
+        GLib.Test.message ("Writing down to file: Creating a new File");
+        ostream = file.create (GLib.FileCreateFlags.NONE, cancellable);
+        ostream.splice (b, GLib.OutputStreamSpliceFlags.NONE);
+        ostream.close ();
+      }
+    } catch (GLib.Error e) {
+      GLib.warning ("Error on Save to file: "+e.message);
+      return false;
+    }
     return true;
   }
   public virtual void write_document (Xml.TextWriter tw)
diff --git a/gxml/xlibxml.c b/gxml/xlibxml.c
index 1365580..887338a 100644
--- a/gxml/xlibxml.c
+++ b/gxml/xlibxml.c
@@ -23,11 +23,13 @@
 
 void* gxml_doc_get_intsubset_entities (xmlDoc *doc)
 {
+  g_return_if_fail (doc != NULL);
   return doc->intSubset->entities;
 }
 
 int gxml_validate_name (xmlChar* name, int space)
 {
+  g_return_if_fail (name != NULL);
   return xmlValidateName (name, space);
 }
 
@@ -43,20 +45,34 @@ xmlErrorPtr gxml_get_last_error ()
 
 xmlNsPtr* gxml_doc_get_ns_list (xmlDoc* doc, xmlNode* node)
 {
+  g_return_if_fail (doc != NULL);
+  g_return_if_fail (node != NULL);
   return xmlGetNsList (doc, node);
 }
 
 xmlTextWriterPtr gxml_new_text_writer_doc (xmlDoc** doc)
 {
+  g_return_if_fail (doc != NULL);
   return xmlNewTextWriterDoc (doc, 0);
 }
 
+xmlTextWriterPtr gxml_new_text_writer_memory (xmlBufferPtr buffer, gint compression)
+{
+  g_return_if_fail (buffer != NULL);
+  return xmlNewTextWriterMemory (buffer, compression);
+}
+
 int gxml_text_writer_write_cdata (xmlTextWriterPtr tw, const xmlChar* text)
 {
+  g_return_if_fail (tw != NULL);
+  g_return_if_fail (text != NULL);
   return xmlTextWriterWriteCDATA (tw, text);
 }
 
 int gxml_text_writer_write_pi (xmlTextWriterPtr tw, const xmlChar* target, const xmlChar* data)
 {
+  g_return_if_fail (tw != NULL);
+  g_return_if_fail (target != NULL);
+  g_return_if_fail (data != NULL);
   return xmlTextWriterWritePI (tw, target, data);
 }
diff --git a/gxml/xlibxml.h b/gxml/xlibxml.h
index 6ec601c..ea173e7 100644
--- a/gxml/xlibxml.h
+++ b/gxml/xlibxml.h
@@ -24,12 +24,15 @@
 #include <libxml/tree.h>
 #include <libxml/parser.h>
 #include <libxml/xmlwriter.h>
+#include <glib.h>
 
 void*       gxml_doc_get_intsubset_entities    (xmlDoc *doc);
 int         gxml_validate_name                 (xmlChar* name, int space);
 xmlErrorPtr gxml_parser_context_get_last_error (void* ctx);
 xmlErrorPtr gxml_get_last_error                ();
 xmlNsPtr*   gxml_doc_get_ns_list               (xmlDoc* doc, xmlNode* node);
+xmlTextWriterPtr gxml_new_text_writer_doc      (xmlDoc** doc);
+xmlTextWriterPtr gxml_new_text_writer_memory   (xmlBufferPtr buffer, gint compression);
 int         gxml_text_writer_write_cdata       (xmlTextWriter* tw, const xmlChar* text);
 int         gxml_text_writer_write_pi          (xmlTextWriter* tw, const xmlChar* target, const xmlChar* 
data);
 
diff --git a/test/TwDocumentTest.vala b/test/TwDocumentTest.vala
index 0d70907..4be9429 100644
--- a/test/TwDocumentTest.vala
+++ b/test/TwDocumentTest.vala
@@ -23,6 +23,12 @@
 using GXml;
 
 class TwDocumentTest : GXmlTest {
+       public class TwTestObject : SerializableObjectModel
+       {
+               public string name { get; set; }
+               public override string node_name () { return "Test"; }
+               public override string to_string () { return "TestNode"; }
+       }
        public static void add_tests () {
                Test.add_func ("/gxml/tw-document", () => {
                        try {
@@ -71,13 +77,15 @@ class TwDocumentTest : GXmlTest {
                                        assert (d.root != null);
                                        assert (d.root.name == "root");
                                        assert (d.root.value == "");
-                                       d.save ();
+                                       GLib.Test.message ("Saving document to: "+f.get_path ());
+                                       assert (d.save ());
+                                       GLib.Test.message ("Reading saved document to: "+f.get_path ());
+                                       assert (f.query_exists ());
                                        var istream = f.read ();
-                                       uint8[] buffer = new uint8[2048];
-                                       istream.read_all (buffer, null);
-                                       istream.close ();
-                                       assert ("<?xml version=\"1.0\"?>" in ((string)buffer));
-                                       assert ("<root/>" in ((string)buffer));
+                                       var ostream = new MemoryOutputStream.resizable ();
+                                       ostream.splice (istream, 0);
+                                       assert ("<?xml version=\"1.0\"?>" in ((string)ostream.data));
+                                       assert ("<root/>" in ((string)ostream.data));
                                }
                                catch (GLib.Error e) {
 #if DEBUG
@@ -326,7 +334,41 @@ class TwDocumentTest : GXmlTest {
                                assert_not_reached ();
                        }
                });
-               
+               Test.add_func ("/gxml/tw-document/save/backup", () => {
+                               try {
+                                       var f = GLib.File.new_for_path 
(GXmlTestConfig.TEST_SAVE_DIR+"/tw-test.xml");
+                                       if (f.query_exists ()) f.delete ();
+                                       var ot = new TwTestObject ();
+                                       ot.name = "test1";
+                                       var dt = new TwDocument ();
+                                       ot.serialize (dt);
+                                       dt.save_to (f);
+                                       var d = new TwDocument ();
+                                       var e = d.create_element ("root");
+                                       d.childs.add (e);
+                                       assert (d.childs.size == 1);
+                                       assert (d.root != null);
+                                       assert (d.root.name == "root");
+                                       assert (d.root.value == "");
+                                       d.save_to (f);
+                                       assert (f.query_exists ());
+                                       var bf = GLib.File.new_for_path 
(GXmlTestConfig.TEST_SAVE_DIR+"/tw-test.xml~");
+                                       assert (bf.query_exists ());
+                                       var istream = f.read ();
+                                       var b = new MemoryOutputStream.resizable ();
+                                       b.splice (istream, 0);
+                                       assert ("<?xml version=\"1.0\"?>" in ((string)b.data));
+                                       assert ("<root/>" in ((string)b.data));
+                                       f.delete ();
+                                       bf.delete ();
+                               }
+                               catch (GLib.Error e) {
+#if DEBUG
+                                       GLib.message (@"ERROR: $(e.message)");
+#endif
+                                       assert_not_reached ();
+                               }
+                       });
                Test.add_func ("/gxml/tw-document/to_string", () => {
                        var doc = new TwDocument ();
                        var r = doc.create_element ("root");
diff --git a/vapi/xlibxml-1.0.vapi b/vapi/xlibxml-1.0.vapi
index 17fa24d..282a962 100644
--- a/vapi/xlibxml-1.0.vapi
+++ b/vapi/xlibxml-1.0.vapi
@@ -38,6 +38,8 @@ namespace Xmlx {
   public static Xml.Ns*[] doc_get_ns_list (Xml.Doc* doc, Xml.Node* node);
   [CCode (cname = "gxml_new_text_writer_doc", cheader_filename = "gxml/xlibxml.h")]
   public static Xml.TextWriter new_text_writer_doc (ref Xml.Doc doc);
+  [CCode (cname = "gxml_new_text_writer_memory", cheader_filename = "gxml/xlibxml.h")]
+  public static Xml.TextWriter new_text_writer_memory (Xml.Buffer buffer, int compression);
   [CCode (cname = "gxml_text_writer_write_cdata", cheader_filename = "gxml/xlibxml.h")]
   public static int text_writer_write_cdata (Xml.TextWriter tw, string text);
   [CCode (cname = "gxml_text_writer_write_pi", cheader_filename = "gxml/xlibxml.h")]