chore: initialize Gitea v1.27.2 fork

Includes direct password setup links in registration emails.

Assisted-by: Codex:GPT-5

services/auth/source/oauth2/providers_test.go

@@ -0,0 +1,62 @@
+// Copyright 2024 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package oauth2
+
+import (
+	"time"
+
+	"github.com/markbates/goth"
+	"golang.org/x/oauth2"
+)
+
+type fakeProvider struct{}
+
+func (p *fakeProvider) Name() string {
+	return "fake"
+}
+
+func (p *fakeProvider) SetName(name string) {}
+
+func (p *fakeProvider) BeginAuth(state string) (goth.Session, error) {
+	return nil, nil //nolint:nilnil // the auth method is not applicable
+}
+
+func (p *fakeProvider) UnmarshalSession(string) (goth.Session, error) {
+	return nil, nil //nolint:nilnil // the auth method is not applicable
+}
+
+func (p *fakeProvider) FetchUser(goth.Session) (goth.User, error) {
+	return goth.User{}, nil
+}
+
+func (p *fakeProvider) Debug(bool) {
+}
+
+func (p *fakeProvider) RefreshToken(refreshToken string) (*oauth2.Token, error) {
+	switch refreshToken {
+	case "expired":
+		return nil, &oauth2.RetrieveError{
+			ErrorCode: "invalid_grant",
+		}
+	default:
+		return &oauth2.Token{
+			AccessToken:  "token",
+			TokenType:    "Bearer",
+			RefreshToken: "refresh",
+			Expiry:       time.Now().Add(time.Hour),
+		}, nil
+	}
+}
+
+func (p *fakeProvider) RefreshTokenAvailable() bool {
+	return true
+}
+
+func init() {
+	RegisterGothProvider(
+		NewSimpleProvider("fake", "Fake", []string{"account"},
+			func(clientKey, secret, callbackURL string, scopes ...string) goth.Provider {
+				return &fakeProvider{}
+			}))
+}