make link clickable

spec/page/link_spec.cr

@@ -14,4 +14,12 @@ describe "Mechanize Page Link test" do
     link = page.links.first
     link.text.should eq "link text"
   end
+
+  it "is clickable and returns page" do
+    agent = Mechanize.new
+    page = agent.get("http://example.com/link")
+    link = page.links.first
+    page = link.click
+    page.uri.to_s.should eq "http://example.com/"
+  end
 end

src/mechanize.cr

@@ -113,4 +113,10 @@ class Mechanize
   def max_history=(length)
     history.max_size = length
   end
+
+  # click link, and return page.
+  def click(link)
+    href = link.href
+    get href
+  end
 end

src/mechanize/page/link.cr

@@ -12,4 +12,9 @@ class MechanizeCr::PageContent::Link
     @href = node.fetch("href", "")
     @text = node.inner_text
   end
+
+  # click on this link
+  def click
+    @mech.click self
+  end
 end