[gxml] Implemented CssSelectorParser E:first-child pseudo selector

[Daniel Espinosa Ortiz <despinosa src gnome org>]

commit bdb294a3e956331ba4866e1cd36a5362a31e37e4
Author: Daniel Espinosa <esodan gmail com>
Date:   Fri Sep 8 09:20:16 2017 -0700

    Implemented CssSelectorParser E:first-child pseudo selector

 gxml/CssSelectorParser.vala |    9 +++++
 test/CssSelectorTest.vala   |   69 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 78 insertions(+), 0 deletions(-)
---
diff --git a/gxml/CssSelectorParser.vala b/gxml/CssSelectorParser.vala
index fbcffea..7610d76 100644
--- a/gxml/CssSelectorParser.vala
+++ b/gxml/CssSelectorParser.vala
@@ -381,6 +381,15 @@ public class GXml.CssSelectorParser : GLib.Object {
                                if (s.data.down () == "empty") {
                                        if (!element.has_child_nodes ()) return true;
                                }
+                               if (s.data.down () == "fist-child") {
+                                       if (element.parent_node == null) return false;
+                                       if (!(element.parent_node is DomElement)) return false;
+                                       if (element is GomElement)
+                                               if (element == (element.parent_node as 
DomParentNode).first_element_child) return true;
+                                       if (element is GElement)
+                                               if ((element as GNode).get_internal_node () 
+                                                                       == ((element.parent_node as 
DomParentNode).first_element_child as GNode).get_internal_node ()) return true;
+                               }
                        }
                        if (s.selector_type == CssSelectorType.CLASS) {
                                var p = element.get_attribute ("class");
diff --git a/test/CssSelectorTest.vala b/test/CssSelectorTest.vala
index 0303331..0ac6159 100644
--- a/test/CssSelectorTest.vala
+++ b/test/CssSelectorTest.vala
@@ -527,5 +527,74 @@ class CssSelectorTest : GXmlTest {
                                warning ("ERROR: "+e.message);
                        }
                });
+               Test.add_func ("/gxml/css-selector/pseudo/first-child", () => {
+                       try {
+                               var cp = new CssSelectorParser ();
+                               cp.parse ("second:first-child");
+                               foreach (CssSelectorData sel in cp.selectors) {
+                                       message ("Type: "+sel.selector_type.to_string ()+" : "+sel.data+" : 
"+sel.value);
+                               }
+                               assert (cp.selectors.size == 3);
+                               var s = cp.selectors[0];
+                               assert (s != null);
+                               assert (s.selector_type == CssSelectorType.ELEMENT);
+                               var si = cp.selectors[1];
+                               assert (si != null);
+                               assert (si.selector_type == CssSelectorType.INSIDE);
+                               var sa = cp.selectors[2];
+                               assert (sa != null);
+                               assert (sa.selector_type == CssSelectorType.PSEUDO);
+                               var d = new GomDocument ();
+                               var r = d.create_element ("toplevel");
+                               d.append_child (r);
+                               var c1 = d.create_element ("child");
+                               r.append_child (c1);
+                               var c2 = d.create_element ("child");
+                               c2.set_attribute ("prop", "subval");
+                               r.append_child (c2);
+                               var c3 = d.create_element ("child");
+                               c3.set_attribute ("prop", "techval");
+                               r.append_child (c3);
+                               var c4 = d.create_element ("child");
+                               c4.set_attribute ("prop", "secondaryvalue");
+                               r.append_child (c4);
+                               var c5 = d.create_element ("second");
+                               c3.append_child (c5);
+                               var c6 = d.create_element ("second");
+                               c4.append_child (c6);
+                               assert (!cp.match (r));
+                               assert (!cp.match (c1));
+                               assert (!cp.match (c2));
+                               assert (!cp.match (c3));
+                               assert (!cp.match (c4));
+                               assert (cp.match (c5));
+                               assert (cp.match (c6));
+                               var d2 = new GDocument () as DomDocument;
+                               var r2 = d2.create_element ("toplevel");
+                               d2.append_child (r2);
+                               var c1g = d2.create_element ("child");
+                               r2.append_child (c1g);
+                               var c2g = d2.create_element ("child");
+                               c2g.set_attribute ("prop", "subval");
+                               r2.append_child (c2g);
+                               var c3g = d2.create_element ("child");
+                               c3g.set_attribute ("prop", "techval");
+                               r2.append_child (c3g);
+                               var c4g = d2.create_element ("child");
+                               c4g.set_attribute ("prop", "secondaryvalue");
+                               r2.append_child (c4g);
+                               var c5g = d.create_element ("second");
+                               c3g.append_child (c5g);
+                               var c6g = d.create_element ("second");
+                               c4g.append_child (c6g);
+                               assert (cp.match (r));
+                               assert (!cp.match (c1));
+                               assert (!cp.match (c2));
+                               assert (!cp.match (c3));
+                               assert (!cp.match (c4));
+                       } catch (GLib.Error e){
+                               warning ("ERROR: "+e.message);
+                       }
+               });
        }
 }