Grand test fixup (#138)

* start fixing up tests

* fix up tests + automate with drone

* fiddle with linting

* messing about with drone.yml

* some more fiddling

* hmmm

* add cache

* add vendor directory

* verbose

* ci updates

* update some little things

* update sig

vendor/github.com/superseriousbusiness/oauth2/v4/manage/util.go

@@ -0,0 +1,30 @@
+package manage
+
+import (
+	"net/url"
+	"strings"
+
+	"github.com/superseriousbusiness/oauth2/v4/errors"
+)
+
+type (
+	// ValidateURIHandler validates that redirectURI is contained in baseURI
+	ValidateURIHandler func(baseURI, redirectURI string) error
+)
+
+// DefaultValidateURI validates that redirectURI is contained in baseURI
+func DefaultValidateURI(baseURI string, redirectURI string) error {
+	base, err := url.Parse(baseURI)
+	if err != nil {
+		return err
+	}
+
+	redirect, err := url.Parse(redirectURI)
+	if err != nil {
+		return err
+	}
+	if !strings.HasSuffix(redirect.Host, base.Host) {
+		return errors.ErrInvalidRedirectURI
+	}
+	return nil
+}