[gxml] Implemented CssSelectorParser E[foo^="bar"] selector

[Daniel Espinosa Ortiz <despinosa src gnome org>]

commit 978451f08e24c9a97ff243f781e51b53693028a6
Author: Daniel Espinosa <esodan gmail com>
Date:   Fri Sep 8 07:57:06 2017 -0700

    Implemented CssSelectorParser E[foo^="bar"] selector

 gxml/CssSelectorParser.vala |    5 +++++
 test/CssSelectorTest.vala   |   40 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 45 insertions(+), 0 deletions(-)
---
diff --git a/gxml/CssSelectorParser.vala b/gxml/CssSelectorParser.vala
index 10805b4..4a6cee1 100644
--- a/gxml/CssSelectorParser.vala
+++ b/gxml/CssSelectorParser.vala
@@ -338,6 +338,11 @@ public class GXml.CssSelectorParser : GLib.Object {
                                var tl = new GDomTokenList (element, s.data);
                                if (tl.contains (s.value)) return true;
                        }
+                       if (is_element && s.selector_type == CssSelectorType.ATTRIBUTE_START_WITH) {
+                               var p = element.get_attribute (s.data);
+                               if (p == null) return false;
+                               if (p.has_prefix (s.value)) return true;
+                       }
                        if (s.selector_type == CssSelectorType.CLASS) {
                                var p = element.get_attribute ("class");
                                if (p == null) return false;
diff --git a/test/CssSelectorTest.vala b/test/CssSelectorTest.vala
index 3b06a6a..21110e5 100644
--- a/test/CssSelectorTest.vala
+++ b/test/CssSelectorTest.vala
@@ -134,6 +134,46 @@ class CssSelectorTest : GXmlTest {
                                warning ("ERROR: "+e.message);
                        }
                });
+               Test.add_func ("/gxml/css-selector/element/attribute/starts_with", () => {
+                       try {
+                               var cp = new CssSelectorParser ();
+                               cp.parse ("child[prop^=\"val\"]");
+                               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.ATTRIBUTE_START_WITH);
+                               var d = new GomDocument ();
+                               var r = d.create_element ("root");
+                               d.append_child (r);
+                               var c1 = d.create_element ("child");
+                               r.append_child (c1);
+                               var c2 = d.create_element ("child");
+                               c2.set_attribute ("prop", "val");
+                               r.append_child (c2);
+                               var c3 = d.create_element ("child");
+                               c3.set_attribute ("prop", "value");
+                               r.append_child (c3);
+                               var c4 = d.create_element ("child");
+                               c4.set_attribute ("prop", "secondaryvalue");
+                               r.append_child (c4);
+                               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);
+                       }
+               });
                Test.add_func ("/gxml/css-selector/element/attribute-value", () => {
                        try {
                                var cp = new CssSelectorParser ();