add head method

spec/http_spec.cr

@@ -12,6 +12,7 @@ WebMock.stub(:put, "http://example.com/put")
 WebMock.stub(:delete, "http://example.com/delete")
   .with(body: "hello")
   .to_return(body: "success")
+WebMock.stub(:head, "http://example.com/head")
 
 describe "Mechanize HTTP test" do
   it "simple GET" do
@@ -61,6 +62,13 @@ describe "Mechanize HTTP test" do
     page.code.should eq 200
   end
 
+  it "HEAD" do
+    agent = Mechanize.new
+    page = agent.head("http://example.com/head")
+    page.body.should eq ""
+    page.code.should eq 200
+  end
+
   it "can escape non-ascii character" do
     agent = Mechanize.new
     page = agent.get("http://example.com/あああ")

src/mechanize.cr

@@ -135,6 +135,23 @@ class Mechanize
     page
   end
 
+  # Send HEAD request to specified uri with headers.
+  #
+  # Examples (send HEAD request to http://example.com/)
+  #
+  # ```
+  # agent = Mechanize.new
+  # agent.head("http://example.com")
+  # ```
+  def head(uri : String | URI,
+           headers = ::HTTP::Headers.new) : Mechanize::Page
+    method = :head
+    page = @agent.fetch uri, method, headers
+    add_to_history(page)
+    # yield page if block_given?
+    page
+  end
+
   # get the value of request headers.
   #
   # ```

src/mechanize/http/agent.cr

@@ -76,6 +76,8 @@ class Mechanize
             ::HTTP::Client.put(uri, headers: request_headers, body: body)
           when :delete
             ::HTTP::Client.delete(uri, headers: request_headers, body: body)
+          when :head
+            ::HTTP::Client.head(uri, headers: request_headers)
           end
         end
       end