Add Cookie#inspect

spec/std/http/cookie_spec.cr

@@ -173,6 +173,13 @@ module HTTP
       end
     end
 
+    describe "#inspect" do
+      it "stringifies" do
+        HTTP::Cookie.new("foo", "bar").inspect.should eq %(HTTP::Cookie["foo=bar"])
+        HTTP::Cookie.new("x", "y", domain: "example.com", path: "/foo", expires: Time.unix(1257894000), samesite: :lax).inspect.should eq %(HTTP::Cookie["x=y; domain=example.com; path=/foo; expires=Tue, 10 Nov 2009 23:00:00 GMT; SameSite=Lax"])
+      end
+    end
+
     describe "#valid? & #validate!" do
       it "raises on invalid cookie with __Secure- prefix" do
         cookie = HTTP::Cookie.new "x", "", secure: false

src/http/cookie.cr

@@ -104,6 +104,21 @@ module HTTP
       end
     end
 
+    # Returns an unambiguous string representation of this cookie.
+    #
+    # It uses the `Set-Cookie` serialization from `#to_set_cookie_header` which
+    # represents the full state of the cookie.
+    #
+    # ```
+    # HTTP::Cookie.new("foo", "bar").inspect                        # => HTTP::Cookie["foo=bar"]
+    # HTTP::Cookie.new("foo", "bar", domain: "example.com").inspect # => HTTP::Cookie["foo=bar; domain=example.com"]
+    # ```
+    def inspect(io : IO) : Nil
+      io << "HTTP::Cookie["
+      to_s.inspect(io)
+      io << "]"
+    end
+
     # Returns a string representation of this cookie.
     #
     # It uses the `Set-Cookie` serialization from `#to_set_cookie_header` which