fix(lib): make ClearCookie respect the dynamic cookie name (#500)

Previously this made ClearCookie always clear cookies by name even when
CookieDomain was set. This change fixes this and adds tests to make sure
that this doesn't happen again.

Signed-off-by: Xe Iaso <me@xeiaso.net>

lib/http_test.go

@@ -0,0 +1,58 @@
+package lib
+
+import (
+	"net/http/httptest"
+	"testing"
+
+	"github.com/TecharoHQ/anubis"
+)
+
+func TestClearCookie(t *testing.T) {
+	srv := spawnAnubis(t, Options{})
+	rw := httptest.NewRecorder()
+
+	srv.ClearCookie(rw)
+
+	resp := rw.Result()
+
+	cookies := resp.Cookies()
+
+	if len(cookies) != 1 {
+		t.Errorf("wanted 1 cookie, got %d cookies", len(cookies))
+	}
+
+	ckie := cookies[0]
+
+	if ckie.Name != anubis.CookieName {
+		t.Errorf("wanted cookie named %q, got cookie named %q", anubis.CookieName, ckie.Name)
+	}
+
+	if ckie.MaxAge != -1 {
+		t.Errorf("wanted cookie max age of -1, got: %d", ckie.MaxAge)
+	}
+}
+
+func TestClearCookieWithDomain(t *testing.T) {
+	srv := spawnAnubis(t, Options{CookieDomain: "techaro.lol"})
+	rw := httptest.NewRecorder()
+
+	srv.ClearCookie(rw)
+
+	resp := rw.Result()
+
+	cookies := resp.Cookies()
+
+	if len(cookies) != 1 {
+		t.Errorf("wanted 1 cookie, got %d cookies", len(cookies))
+	}
+
+	ckie := cookies[0]
+
+	if ckie.Name != srv.cookieName {
+		t.Errorf("wanted cookie named %q, got cookie named %q", srv.cookieName, ckie.Name)
+	}
+
+	if ckie.MaxAge != -1 {
+		t.Errorf("wanted cookie max age of -1, got: %d", ckie.MaxAge)
+	}
+}