refactor: prepare to decouple the "model migration" package and "models" package (#38533)

Migrations should never use model structs directly, because the model
structs can be different in different releases. e.g. if one migration uses
"User" model, it works in the early releases, then one day, when the
User model changes, the migration breaks because it will use the
new (incorrect) User model, it should only use the old User model.

The same to "modules/structs".

---------

Signed-off-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: delvh <dev.lh@web.de>

modelmigration/v1_22/v286_test.go

@@ -0,0 +1,118 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package v1_22
+
+import (
+	"testing"
+
+	"gitea.dev/modelmigration/base"
+	"gitea.dev/modelmigration/migrationtest"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func PrepareOldRepository(t *testing.T) (base.EngineMigration, func()) {
+	type Repository struct { // old struct
+		ID int64 `xorm:"pk autoincr"`
+	}
+
+	type CommitStatus struct {
+		ID          int64
+		ContextHash string `xorm:"char(40) index"`
+	}
+
+	type RepoArchiver struct {
+		ID       int64
+		RepoID   int64  `xorm:"index unique(s)"`
+		Type     int    `xorm:"unique(s)"`
+		CommitID string `xorm:"VARCHAR(40) unique(s)"`
+	}
+
+	type ReviewState struct {
+		ID        int64
+		UserID    int64  `xorm:"NOT NULL UNIQUE(pull_commit_user)"`
+		PullID    int64  `xorm:"NOT NULL INDEX UNIQUE(pull_commit_user) DEFAULT 0"`
+		CommitSHA string `xorm:"NOT NULL VARCHAR(40) UNIQUE(pull_commit_user)"`
+	}
+
+	type Comment struct {
+		ID        int64
+		CommitSHA string
+	}
+
+	type PullRequest struct {
+		ID             int64
+		CommitSHA      string
+		MergeBase      string
+		MergedCommitID string
+	}
+
+	type Release struct {
+		ID   int64
+		Sha1 string
+	}
+
+	type RepoIndexerStatus struct {
+		ID        int64
+		CommitSHA string
+	}
+
+	type Review struct {
+		ID       int64
+		CommitID string
+	}
+
+	// Prepare and load the testing database
+	return migrationtest.PrepareTestEnv(t, 0,
+		new(Repository),
+		new(CommitStatus),
+		new(RepoArchiver),
+		new(ReviewState),
+		new(Review),
+		new(Comment),
+		new(PullRequest),
+		new(Release),
+		new(RepoIndexerStatus),
+	)
+}
+
+func Test_RepositoryFormat(t *testing.T) {
+	x, deferable := PrepareOldRepository(t)
+	defer deferable()
+
+	assert.NoError(t, AdjustDBForSha256(x))
+
+	type Repository struct {
+		ID               int64  `xorm:"pk autoincr"`
+		ObjectFormatName string `xorg:"not null default('sha1')"`
+	}
+
+	repo := new(Repository)
+
+	// check we have some records to migrate
+	count, err := x.Count(new(Repository))
+	assert.NoError(t, err)
+	assert.EqualValues(t, 4, count)
+
+	repo.ObjectFormatName = "sha256"
+	_, err = x.Insert(repo)
+	assert.NoError(t, err)
+	id := repo.ID
+
+	count, err = x.Count(new(Repository))
+	assert.NoError(t, err)
+	assert.EqualValues(t, 5, count)
+
+	repo = new(Repository)
+	ok, err := x.ID(2).Get(repo)
+	assert.NoError(t, err)
+	assert.True(t, ok)
+	assert.Equal(t, "sha1", repo.ObjectFormatName)
+
+	repo = new(Repository)
+	ok, err = x.ID(id).Get(repo)
+	assert.NoError(t, err)
+	assert.True(t, ok)
+	assert.Equal(t, "sha256", repo.ObjectFormatName)
+}