Create Proper Migration Tests (#15116)

* Create Proper Migration tests

Unfortunately our testing regime has so far meant that migrations do not
get proper testing.

This PR begins the process of creating migration tests for this.

* Add test for v176

* fix mssql drop db

Signed-off-by: Andrew Thornton <art27@cantab.net>

Makefile

@@ -89,7 +89,7 @@ LDFLAGS := $(LDFLAGS) -X "main.MakeVersion=$(MAKE_VERSION)" -X "main.Version=$(G
 
 LINUX_ARCHS ?= linux/amd64,linux/386,linux/arm-5,linux/arm-6,linux/arm64
 
-GO_PACKAGES ?= $(filter-out code.gitea.io/gitea/integrations/migration-test,$(filter-out code.gitea.io/gitea/integrations,$(shell $(GO) list -mod=vendor ./... | grep -v /vendor/)))
+GO_PACKAGES ?= $(filter-out code.gitea.io/gitea/models/migrations code.gitea.io/gitea/integrations/migration-test code.gitea.io/gitea/integrations,$(shell $(GO) list -mod=vendor ./... | grep -v /vendor/))
 
 FOMANTIC_CONFIGS := semantic.json web_src/fomantic/theme.config.less web_src/fomantic/_site/globals/site.variables
 FOMANTIC_DEST := web_src/fomantic/build/semantic.js web_src/fomantic/build/semantic.css
@@ -399,8 +399,9 @@ test-sqlite\#%: integrations.sqlite.test generate-ini-sqlite
 	GITEA_ROOT="$(CURDIR)" GITEA_CONF=integrations/sqlite.ini ./integrations.sqlite.test -test.run $(subst .,/,$*)
 
 .PHONY: test-sqlite-migration
-test-sqlite-migration:  migrations.sqlite.test generate-ini-sqlite
+test-sqlite-migration:  migrations.sqlite.test migrations.individual.sqlite.test generate-ini-sqlite
 	GITEA_ROOT="$(CURDIR)" GITEA_CONF=integrations/sqlite.ini ./migrations.sqlite.test
+	GITEA_ROOT="$(CURDIR)" GITEA_CONF=integrations/sqlite.ini ./migrations.individual.sqlite.test
 
 generate-ini-mysql:
 	sed -e 's|{{TEST_MYSQL_HOST}}|${TEST_MYSQL_HOST}|g' \
@@ -419,8 +420,9 @@ test-mysql\#%: integrations.mysql.test generate-ini-mysql
 	GITEA_ROOT="$(CURDIR)" GITEA_CONF=integrations/mysql.ini ./integrations.mysql.test -test.run $(subst .,/,$*)
 
 .PHONY: test-mysql-migration
-test-mysql-migration: migrations.mysql.test generate-ini-mysql
+test-mysql-migration: migrations.mysql.test migrations.individual.mysql.test generate-ini-mysql
 	GITEA_ROOT="$(CURDIR)" GITEA_CONF=integrations/mysql.ini ./migrations.mysql.test
+	GITEA_ROOT="$(CURDIR)" GITEA_CONF=integrations/mysql.ini ./migrations.individual.mysql.test
 
 generate-ini-mysql8:
 	sed -e 's|{{TEST_MYSQL8_HOST}}|${TEST_MYSQL8_HOST}|g' \
@@ -439,8 +441,9 @@ test-mysql8\#%: integrations.mysql8.test generate-ini-mysql8
 	GITEA_ROOT="$(CURDIR)" GITEA_CONF=integrations/mysql8.ini ./integrations.mysql8.test -test.run $(subst .,/,$*)
 
 .PHONY: test-mysql8-migration
-test-mysql8-migration: migrations.mysql8.test generate-ini-mysql8
+test-mysql8-migration: migrations.mysql8.test migrations.individual.mysql8.test generate-ini-mysql8
 	GITEA_ROOT="$(CURDIR)" GITEA_CONF=integrations/mysql8.ini ./migrations.mysql8.test
+	GITEA_ROOT="$(CURDIR)" GITEA_CONF=integrations/mysql8.ini ./migrations.individual.mysql8.test
 
 generate-ini-pgsql:
 	sed -e 's|{{TEST_PGSQL_HOST}}|${TEST_PGSQL_HOST}|g' \
@@ -460,8 +463,9 @@ test-pgsql\#%: integrations.pgsql.test generate-ini-pgsql
 	GITEA_ROOT="$(CURDIR)" GITEA_CONF=integrations/pgsql.ini ./integrations.pgsql.test -test.run $(subst .,/,$*)
 
 .PHONY: test-pgsql-migration
-test-pgsql-migration: migrations.pgsql.test generate-ini-pgsql
+test-pgsql-migration: migrations.pgsql.test migrations.individual.pgsql.test generate-ini-pgsql
 	GITEA_ROOT="$(CURDIR)" GITEA_CONF=integrations/pgsql.ini ./migrations.pgsql.test
+	GITEA_ROOT="$(CURDIR)" GITEA_CONF=integrations/pgsql.ini ./migrations.individual.pgsql.test
 
 generate-ini-mssql:
 	sed -e 's|{{TEST_MSSQL_HOST}}|${TEST_MSSQL_HOST}|g' \
@@ -480,8 +484,9 @@ test-mssql\#%: integrations.mssql.test generate-ini-mssql
 	GITEA_ROOT="$(CURDIR)" GITEA_CONF=integrations/mssql.ini ./integrations.mssql.test -test.run $(subst .,/,$*)
 
 .PHONY: test-mssql-migration
-test-mssql-migration: migrations.mssql.test generate-ini-mssql
+test-mssql-migration: migrations.mssql.test migrations.individual.mssql.test generate-ini-mssql
 	GITEA_ROOT="$(CURDIR)" GITEA_CONF=integrations/mssql.ini ./migrations.mssql.test -test.failfast
+	GITEA_ROOT="$(CURDIR)" GITEA_CONF=integrations/mssql.ini ./migrations.individual.mssql.test -test.failfast
 
 .PHONY: bench-sqlite
 bench-sqlite: integrations.sqlite.test generate-ini-sqlite
@@ -541,6 +546,26 @@ migrations.mssql.test: $(GO_SOURCES)
 migrations.sqlite.test: $(GO_SOURCES)
 	$(GO) test $(GOTESTFLAGS) -c code.gitea.io/gitea/integrations/migration-test -o migrations.sqlite.test -tags '$(TEST_TAGS)'
 
+.PHONY: migrations.individual.mysql.test
+migrations.individual.mysql.test: $(GO_SOURCES)
+	$(GO) test $(GOTESTFLAGS) -c code.gitea.io/gitea/models/migrations -o migrations.individual.mysql.test
+
+.PHONY: migrations.individual.mysql8.test
+migrations.individual.mysql8.test: $(GO_SOURCES)
+	$(GO) test $(GOTESTFLAGS) -c code.gitea.io/gitea/models/migrations -o migrations.individual.mysql8.test
+
+.PHONY: migrations.individual.pgsql.test
+migrations.individual.pgsql.test: $(GO_SOURCES)
+	$(GO) test $(GOTESTFLAGS) -c code.gitea.io/gitea/models/migrations -o migrations.individual.pgsql.test
+
+.PHONY: migrations.individual.mssql.test
+migrations.individual.mssql.test: $(GO_SOURCES)
+	$(GO) test $(GOTESTFLAGS) -c code.gitea.io/gitea/models/migrations -o migrations.individual.mssql.test
+
+.PHONY: migrations.individual.sqlite.test
+migrations.individual.sqlite.test: $(GO_SOURCES)
+	$(GO) test $(GOTESTFLAGS) -c code.gitea.io/gitea/models/migrations -o migrations.individual.sqlite.test -tags '$(TEST_TAGS)'
+
 .PHONY: check
 check: test
 

models/migrations/fixtures/Test_deleteOrphanedIssueLabels/issue_label.yml

@@ -0,0 +1,29 @@
+# Issue_Label 1 should not be deleted
+-
+  id: 1
+  issue_id: 1
+  label_id: 1
+
+# Issue_label 2 should be deleted
+-
+  id: 2
+  issue_id: 5
+  label_id: 99
+
+# Issue_Label 3 should not be deleted
+-
+  id: 3
+  issue_id: 2
+  label_id: 1
+
+# Issue_Label 4 should not be deleted
+-
+  id: 4
+  issue_id: 2
+  label_id: 4
+
+-
+  id: 5
+  issue_id: 2
+  label_id: 87
+

models/migrations/fixtures/Test_deleteOrphanedIssueLabels/label.yml

@@ -0,0 +1,43 @@
+-
+  id: 1
+  repo_id: 1
+  org_id: 0
+  name: label1
+  color: '#abcdef'
+  num_issues: 2
+  num_closed_issues: 0
+
+-
+  id: 2
+  repo_id: 1
+  org_id: 0
+  name: label2
+  color: '#000000'
+  num_issues: 1
+  num_closed_issues: 1
+-
+  id: 3
+  repo_id: 0
+  org_id:  3
+  name: orglabel3
+  color: '#abcdef'
+  num_issues: 0
+  num_closed_issues: 0
+
+-
+  id: 4
+  repo_id: 0
+  org_id: 3
+  name: orglabel4
+  color: '#000000'
+  num_issues: 1
+  num_closed_issues: 0
+
+-
+  id: 5
+  repo_id: 10
+  org_id: 0
+  name: pull-test-label
+  color: '#000000'
+  num_issues: 0
+  num_closed_issues: 0

models/migrations/fixtures/Test_removeInvalidLabels/comment.yml

@@ -0,0 +1,52 @@
+# type Comment struct {
+#   ID      int64 `xorm:"pk autoincr"`
+#   Type    int   `xorm:"INDEX"`
+#   IssueID int64 `xorm:"INDEX"`
+#   LabelID int64
+# }
+#
+# we are only interested in type 7
+#
+
+-
+  id: 1 # Should remain
+  type: 6
+  issue_id: 1
+  label_id: 0
+  should_remain: true
+-
+  id: 2 # Should remain
+  type: 7
+  issue_id: 1 # repo_id: 1
+  label_id: 1 # repo_id: 1
+  should_remain: true
+-
+  id: 3 # Should remain
+  type: 7
+  issue_id: 2 # repo_id: 2 owner_id: 1
+  label_id: 2 # org_id: 1
+  should_remain: true
+-
+  id: 4 # Should be DELETED
+  type: 7
+  issue_id: 1 # repo_id: 1
+  label_id: 3 # repo_id: 2
+  should_remain: false
+-
+  id: 5 # Should remain
+  type: 7
+  issue_id: 3 # repo_id: 1
+  label_id: 1 # repo_id: 1
+  should_remain: true
+-
+  id: 6 # Should be DELETED
+  type: 7
+  issue_id: 3 # repo_id: 1 owner_id: 2
+  label_id: 2 # org_id: 1
+  should_remain: false
+-
+  id: 7 # Should be DELETED
+  type: 7
+  issue_id: 3 # repo_id: 1 owner_id: 2
+  label_id: 5 # repo_id: 3
+  should_remain: false

models/migrations/fixtures/Test_removeInvalidLabels/issue.yml

@@ -0,0 +1,21 @@
+# type Issue struct {
+#   ID     int64 `xorm:"pk autoincr"`
+#   RepoID int64 `xorm:"INDEX UNIQUE(repo_index)"`
+#   Index  int64 `xorm:"UNIQUE(repo_index)"` // Index in one repository.
+# }
+-
+  id: 1
+  repo_id: 1
+  index: 1
+-
+  id: 2
+  repo_id: 2
+  index: 1
+-
+  id: 3
+  repo_id: 1
+  index: 2
+-
+  id: 4
+  repo_id: 3
+  index: 1

models/migrations/fixtures/Test_removeInvalidLabels/issue_label.yml

@@ -0,0 +1,35 @@
+# type IssueLabel struct {
+#   ID      int64 `xorm:"pk autoincr"`
+#   IssueID int64 `xorm:"UNIQUE(s)"`
+#   LabelID int64 `xorm:"UNIQUE(s)"`
+# }
+-
+  id: 1 # Should remain - matches comment 2
+  issue_id: 1
+  label_id: 1
+  should_remain: true
+-
+  id: 2 # Should remain
+  issue_id: 2
+  label_id: 2
+  should_remain: true
+-
+  id: 3 # Should be deleted
+  issue_id: 1
+  label_id: 3
+  should_remain: false
+-
+  id: 4 # Should remain
+  issue_id: 3
+  label_id: 1
+  should_remain: true
+-
+  id: 5 # Should be deleted
+  issue_id: 3
+  label_id: 2
+  should_remain: false
+-
+  id: 6 # Should be deleted
+  issue_id: 3
+  label_id: 5
+  should_remain: false

models/migrations/fixtures/Test_removeInvalidLabels/label.yml

@@ -0,0 +1,26 @@
+# type Label struct {
+#   ID     int64 `xorm:"pk autoincr"`
+#   RepoID int64 `xorm:"INDEX"`
+#   OrgID  int64 `xorm:"INDEX"`
+# }
+-
+  id: 1
+  repo_id: 1
+  org_id: 0
+-
+  id: 2
+  repo_id: 0
+  org_id: 1
+-
+  id: 3
+  repo_id: 2
+  org_id: 0
+-
+  id: 4
+  repo_id: 1
+  org_id: 0
+-
+  id: 5
+  repo_id: 3
+  org_id: 0
+

models/migrations/fixtures/Test_removeInvalidLabels/repository.yml

@@ -0,0 +1,17 @@
+# type Repository struct {
+#   ID        int64  `xorm:"pk autoincr"`
+#   OwnerID   int64  `xorm:"UNIQUE(s) index"`
+#   LowerName string `xorm:"UNIQUE(s) INDEX NOT NULL"`
+# }
+-
+  id: 1
+  owner_id: 2
+  lower_name: "repo1"
+-
+  id: 2
+  owner_id: 1
+  lower_name: "repo2"
+-
+  id: 3
+  owner_id: 2
+  lower_name: "repo3"

models/migrations/migrations.go

@@ -819,9 +819,24 @@ func dropTableColumns(sess *xorm.Session, tableName string, columnNames ...strin
 		}
 		for _, constraint := range constraints {
 			if _, err := sess.Exec(fmt.Sprintf("ALTER TABLE `%s` DROP CONSTRAINT `%s`", tableName, constraint)); err != nil {
-				return fmt.Errorf("Drop table `%s` constraint `%s`: %v", tableName, constraint, err)
+				return fmt.Errorf("Drop table `%s` default constraint `%s`: %v", tableName, constraint, err)
 			}
 		}
+		sql = fmt.Sprintf("SELECT DISTINCT Name FROM SYS.INDEXES INNER JOIN SYS.INDEX_COLUMNS ON INDEXES.INDEX_ID = INDEX_COLUMNS.INDEX_ID AND INDEXES.OBJECT_ID = INDEX_COLUMNS.OBJECT_ID WHERE INDEXES.OBJECT_ID = OBJECT_ID('%[1]s') AND INDEX_COLUMNS.COLUMN_ID IN (SELECT column_id FROM sys.columns WHERE lower(NAME) IN (%[2]s) AND object_id = OBJECT_ID('%[1]s'))",
+			tableName, strings.ReplaceAll(cols, "`", "'"))
+		constraints = make([]string, 0)
+		if err := sess.SQL(sql).Find(&constraints); err != nil {
+			return fmt.Errorf("Find constraints: %v", err)
+		}
+		for _, constraint := range constraints {
+			if _, err := sess.Exec(fmt.Sprintf("ALTER TABLE `%s` DROP CONSTRAINT IF EXISTS `%s`", tableName, constraint)); err != nil {
+				return fmt.Errorf("Drop table `%s` index constraint `%s`: %v", tableName, constraint, err)
+			}
+			if _, err := sess.Exec(fmt.Sprintf("DROP INDEX IF EXISTS `%[2]s` ON `%[1]s`", tableName, constraint)); err != nil {
+				return fmt.Errorf("Drop index `%[2]s` on `%[1]s`: %v", tableName, constraint, err)
+			}
+		}
+
 		if _, err := sess.Exec(fmt.Sprintf("ALTER TABLE `%s` DROP COLUMN %s", tableName, cols)); err != nil {
 			return fmt.Errorf("Drop table `%s` columns %v: %v", tableName, columnNames, err)
 		}

models/migrations/migrations_test.go

@@ -0,0 +1,338 @@
+// Copyright 2021 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package migrations
+
+import (
+	"database/sql"
+	"fmt"
+	"os"
+	"path"
+	"path/filepath"
+	"runtime"
+	"testing"
+	"time"
+
+	"code.gitea.io/gitea/models"
+	"code.gitea.io/gitea/modules/base"
+	"code.gitea.io/gitea/modules/setting"
+	"code.gitea.io/gitea/modules/timeutil"
+	"code.gitea.io/gitea/modules/util"
+	"github.com/stretchr/testify/assert"
+	"github.com/unknwon/com"
+	"xorm.io/xorm"
+	"xorm.io/xorm/names"
+)
+
+func TestMain(m *testing.M) {
+	giteaRoot := base.SetupGiteaRoot()
+	if giteaRoot == "" {
+		fmt.Println("Environment variable $GITEA_ROOT not set")
+		os.Exit(1)
+	}
+	giteaBinary := "gitea"
+	if runtime.GOOS == "windows" {
+		giteaBinary += ".exe"
+	}
+	setting.AppPath = path.Join(giteaRoot, giteaBinary)
+	if _, err := os.Stat(setting.AppPath); err != nil {
+		fmt.Printf("Could not find gitea binary at %s\n", setting.AppPath)
+		os.Exit(1)
+	}
+
+	giteaConf := os.Getenv("GITEA_CONF")
+	if giteaConf == "" {
+		giteaConf = path.Join(filepath.Dir(setting.AppPath), "integrations/sqlite.ini")
+		fmt.Printf("Environment variable $GITEA_CONF not set - defaulting to %s\n", giteaConf)
+	}
+
+	if !path.IsAbs(giteaConf) {
+		setting.CustomConf = path.Join(giteaRoot, giteaConf)
+	} else {
+		setting.CustomConf = giteaConf
+	}
+
+	setting.SetCustomPathAndConf("", "", "")
+	setting.NewContext()
+	setting.CheckLFSVersion()
+	setting.InitDBConfig()
+	setting.NewLogServices(true)
+
+	exitStatus := m.Run()
+
+	if err := removeAllWithRetry(setting.RepoRootPath); err != nil {
+		fmt.Fprintf(os.Stderr, "os.RemoveAll: %v\n", err)
+	}
+	if err := removeAllWithRetry(setting.AppDataPath); err != nil {
+		fmt.Fprintf(os.Stderr, "os.RemoveAll: %v\n", err)
+	}
+	os.Exit(exitStatus)
+}
+
+func removeAllWithRetry(dir string) error {
+	var err error
+	for i := 0; i < 20; i++ {
+		err = os.RemoveAll(dir)
+		if err == nil {
+			break
+		}
+		time.Sleep(100 * time.Millisecond)
+	}
+	return err
+}
+
+// SetEngine sets the xorm.Engine
+func SetEngine() (*xorm.Engine, error) {
+	x, err := models.GetNewEngine()
+	if err != nil {
+		return x, fmt.Errorf("Failed to connect to database: %v", err)
+	}
+
+	x.SetMapper(names.GonicMapper{})
+	// WARNING: for serv command, MUST remove the output to os.stdout,
+	// so use log file to instead print to stdout.
+	x.SetLogger(models.NewXORMLogger(setting.Database.LogSQL))
+	x.ShowSQL(setting.Database.LogSQL)
+	x.SetMaxOpenConns(setting.Database.MaxOpenConns)
+	x.SetMaxIdleConns(setting.Database.MaxIdleConns)
+	x.SetConnMaxLifetime(setting.Database.ConnMaxLifetime)
+	return x, nil
+}
+
+func deleteDB() error {
+	switch {
+	case setting.Database.UseSQLite3:
+		if err := util.Remove(setting.Database.Path); err != nil {
+			return err
+		}
+		return os.MkdirAll(path.Dir(setting.Database.Path), os.ModePerm)
+
+	case setting.Database.UseMySQL:
+		db, err := sql.Open("mysql", fmt.Sprintf("%s:%s@tcp(%s)/",
+			setting.Database.User, setting.Database.Passwd, setting.Database.Host))
+		if err != nil {
+			return err
+		}
+		defer db.Close()
+
+		if _, err = db.Exec(fmt.Sprintf("DROP DATABASE IF EXISTS %s", setting.Database.Name)); err != nil {
+			return err
+		}
+
+		if _, err = db.Exec(fmt.Sprintf("CREATE DATABASE IF NOT EXISTS %s", setting.Database.Name)); err != nil {
+			return err
+		}
+		return nil
+	case setting.Database.UsePostgreSQL:
+		db, err := sql.Open("postgres", fmt.Sprintf("postgres://%s:%s@%s/?sslmode=%s",
+			setting.Database.User, setting.Database.Passwd, setting.Database.Host, setting.Database.SSLMode))
+		if err != nil {
+			return err
+		}
+		defer db.Close()
+
+		if _, err = db.Exec(fmt.Sprintf("DROP DATABASE IF EXISTS %s", setting.Database.Name)); err != nil {
+			return err
+		}
+
+		if _, err = db.Exec(fmt.Sprintf("CREATE DATABASE %s", setting.Database.Name)); err != nil {
+			return err
+		}
+		db.Close()
+
+		// Check if we need to setup a specific schema
+		if len(setting.Database.Schema) != 0 {
+			db, err = sql.Open("postgres", fmt.Sprintf("postgres://%s:%s@%s/%s?sslmode=%s",
+				setting.Database.User, setting.Database.Passwd, setting.Database.Host, setting.Database.Name, setting.Database.SSLMode))
+			if err != nil {
+				return err
+			}
+			defer db.Close()
+
+			schrows, err := db.Query(fmt.Sprintf("SELECT 1 FROM information_schema.schemata WHERE schema_name = '%s'", setting.Database.Schema))
+			if err != nil {
+				return err
+			}
+			defer schrows.Close()
+
+			if !schrows.Next() {
+				// Create and setup a DB schema
+				_, err = db.Exec(fmt.Sprintf("CREATE SCHEMA %s", setting.Database.Schema))
+				if err != nil {
+					return err
+				}
+			}
+
+			// Make the user's default search path the created schema; this will affect new connections
+			_, err = db.Exec(fmt.Sprintf(`ALTER USER "%s" SET search_path = %s`, setting.Database.User, setting.Database.Schema))
+			if err != nil {
+				return err
+			}
+			return nil
+		}
+	case setting.Database.UseMSSQL:
+		host, port := setting.ParseMSSQLHostPort(setting.Database.Host)
+		db, err := sql.Open("mssql", fmt.Sprintf("server=%s; port=%s; database=%s; user id=%s; password=%s;",
+			host, port, "master", setting.Database.User, setting.Database.Passwd))
+		if err != nil {
+			return err
+		}
+		defer db.Close()
+
+		if _, err = db.Exec(fmt.Sprintf("DROP DATABASE IF EXISTS [%s]", setting.Database.Name)); err != nil {
+			return err
+		}
+		if _, err = db.Exec(fmt.Sprintf("CREATE DATABASE [%s]", setting.Database.Name)); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// prepareTestEnv prepares the test environment and reset the database. The skip parameter should usually be 0.
+// Provide models to be sync'd with the database - in particular any models you expect fixtures to be loaded from.
+//
+// fixtures in `models/migrations/fixtures/<TestName>` will be loaded automatically
+func prepareTestEnv(t *testing.T, skip int, syncModels ...interface{}) (*xorm.Engine, func()) {
+	t.Helper()
+	ourSkip := 2
+	ourSkip += skip
+	deferFn := PrintCurrentTest(t, ourSkip)
+	assert.NoError(t, os.RemoveAll(setting.RepoRootPath))
+
+	assert.NoError(t, com.CopyDir(path.Join(filepath.Dir(setting.AppPath), "integrations/gitea-repositories-meta"),
+		setting.RepoRootPath))
+
+	if err := deleteDB(); err != nil {
+		t.Errorf("unable to reset database: %v", err)
+		return nil, deferFn
+	}
+
+	x, err := SetEngine()
+	assert.NoError(t, err)
+	if x != nil {
+		oldDefer := deferFn
+		deferFn = func() {
+			oldDefer()
+			if err := x.Close(); err != nil {
+				t.Errorf("error during close: %v", err)
+			}
+		}
+	}
+	if err != nil {
+		return x, deferFn
+	}
+
+	if len(syncModels) > 0 {
+		if err := x.Sync2(syncModels...); err != nil {
+			t.Errorf("error during sync: %v", err)
+			return x, deferFn
+		}
+	}
+
+	fixturesDir := filepath.Join(filepath.Dir(setting.AppPath), "models", "migrations", "fixtures", t.Name())
+
+	if _, err := os.Stat(fixturesDir); err == nil {
+		t.Logf("initializing fixtures from: %s", fixturesDir)
+		if err := models.InitFixtures(fixturesDir, x); err != nil {
+			t.Errorf("error whilst initializing fixtures from %s: %v", fixturesDir, err)
+			return x, deferFn
+		}
+		if err := models.LoadFixtures(x); err != nil {
+			t.Errorf("error whilst loading fixtures from %s: %v", fixturesDir, err)
+			return x, deferFn
+		}
+	} else if !os.IsNotExist(err) {
+		t.Errorf("unexpected error whilst checking for existence of fixtures: %v", err)
+	} else {
+		t.Logf("no fixtures found in: %s", fixturesDir)
+	}
+
+	return x, deferFn
+}
+
+func Test_dropTableColumns(t *testing.T) {
+	x, deferable := prepareTestEnv(t, 0)
+	if x == nil || t.Failed() {
+		defer deferable()
+		return
+	}
+	defer deferable()
+
+	type DropTest struct {
+		ID            int64 `xorm:"pk autoincr"`
+		FirstColumn   string
+		ToDropColumn  string `xorm:"unique"`
+		AnotherColumn int64
+		CreatedUnix   timeutil.TimeStamp `xorm:"INDEX created"`
+		UpdatedUnix   timeutil.TimeStamp `xorm:"INDEX updated"`
+	}
+
+	columns := []string{
+		"first_column",
+		"to_drop_column",
+		"another_column",
+		"created_unix",
+		"updated_unix",
+	}
+
+	for i := range columns {
+		x.SetMapper(names.GonicMapper{})
+		if err := x.Sync2(new(DropTest)); err != nil {
+			t.Errorf("unable to create DropTest table: %v", err)
+			return
+		}
+		sess := x.NewSession()
+		if err := sess.Begin(); err != nil {
+			sess.Close()
+			t.Errorf("unable to begin transaction: %v", err)
+			return
+		}
+		if err := dropTableColumns(sess, "drop_test", columns[i:]...); err != nil {
+			sess.Close()
+			t.Errorf("Unable to drop columns[%d:]: %s from drop_test: %v", i, columns[i:], err)
+			return
+		}
+		if err := sess.Commit(); err != nil {
+			sess.Close()
+			t.Errorf("unable to commit transaction: %v", err)
+			return
+		}
+		sess.Close()
+		if err := x.DropTables(new(DropTest)); err != nil {
+			t.Errorf("unable to drop table: %v", err)
+			return
+		}
+		for j := range columns[i+1:] {
+			x.SetMapper(names.GonicMapper{})
+			if err := x.Sync2(new(DropTest)); err != nil {
+				t.Errorf("unable to create DropTest table: %v", err)
+				return
+			}
+			dropcols := append([]string{columns[i]}, columns[j+i+1:]...)
+			sess := x.NewSession()
+			if err := sess.Begin(); err != nil {
+				sess.Close()
+				t.Errorf("unable to begin transaction: %v", err)
+				return
+			}
+			if err := dropTableColumns(sess, "drop_test", dropcols...); err != nil {
+				sess.Close()
+				t.Errorf("Unable to drop columns: %s from drop_test: %v", dropcols, err)
+				return
+			}
+			if err := sess.Commit(); err != nil {
+				sess.Close()
+				t.Errorf("unable to commit transaction: %v", err)
+				return
+			}
+			sess.Close()
+			if err := x.DropTables(new(DropTest)); err != nil {
+				t.Errorf("unable to drop table: %v", err)
+				return
+			}
+		}
+	}
+}

models/migrations/testlogger_test.go

@@ -0,0 +1,188 @@
+// Copyright 2019 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package migrations
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"runtime"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/queue"
+	jsoniter "github.com/json-iterator/go"
+)
+
+var (
+	prefix    string
+	slowTest  = 10 * time.Second
+	slowFlush = 5 * time.Second
+)
+
+// TestLogger is a logger which will write to the testing log
+type TestLogger struct {
+	log.WriterLogger
+}
+
+var writerCloser = &testLoggerWriterCloser{}
+
+type testLoggerWriterCloser struct {
+	sync.RWMutex
+	t []*testing.TB
+}
+
+func (w *testLoggerWriterCloser) setT(t *testing.TB) {
+	w.Lock()
+	w.t = append(w.t, t)
+	w.Unlock()
+}
+
+func (w *testLoggerWriterCloser) Write(p []byte) (int, error) {
+	w.RLock()
+	var t *testing.TB
+	if len(w.t) > 0 {
+		t = w.t[len(w.t)-1]
+	}
+	w.RUnlock()
+	if t != nil && *t != nil {
+		if len(p) > 0 && p[len(p)-1] == '\n' {
+			p = p[:len(p)-1]
+		}
+
+		defer func() {
+			err := recover()
+			if err == nil {
+				return
+			}
+			var errString string
+			errErr, ok := err.(error)
+			if ok {
+				errString = errErr.Error()
+			} else {
+				errString, ok = err.(string)
+			}
+			if !ok {
+				panic(err)
+			}
+			if !strings.HasPrefix(errString, "Log in goroutine after ") {
+				panic(err)
+			}
+		}()
+
+		(*t).Log(string(p))
+		return len(p), nil
+	}
+	return len(p), nil
+}
+
+func (w *testLoggerWriterCloser) Close() error {
+	w.Lock()
+	if len(w.t) > 0 {
+		w.t = w.t[:len(w.t)-1]
+	}
+	w.Unlock()
+	return nil
+}
+
+// PrintCurrentTest prints the current test to os.Stdout
+func PrintCurrentTest(t testing.TB, skip ...int) func() {
+	start := time.Now()
+	actualSkip := 1
+	if len(skip) > 0 {
+		actualSkip = skip[0]
+	}
+	_, filename, line, _ := runtime.Caller(actualSkip)
+
+	if log.CanColorStdout {
+		fmt.Fprintf(os.Stdout, "=== %s (%s:%d)\n", fmt.Formatter(log.NewColoredValue(t.Name())), strings.TrimPrefix(filename, prefix), line)
+	} else {
+		fmt.Fprintf(os.Stdout, "=== %s (%s:%d)\n", t.Name(), strings.TrimPrefix(filename, prefix), line)
+	}
+	writerCloser.setT(&t)
+	return func() {
+		took := time.Since(start)
+		if took > slowTest {
+			if log.CanColorStdout {
+				fmt.Fprintf(os.Stdout, "+++ %s is a slow test (took %v)\n", fmt.Formatter(log.NewColoredValue(t.Name(), log.Bold, log.FgYellow)), fmt.Formatter(log.NewColoredValue(took, log.Bold, log.FgYellow)))
+			} else {
+				fmt.Fprintf(os.Stdout, "+++ %s is a slow tets (took %v)\n", t.Name(), took)
+			}
+		}
+		timer := time.AfterFunc(slowFlush, func() {
+			if log.CanColorStdout {
+				fmt.Fprintf(os.Stdout, "+++ %s ... still flushing after %v ...\n", fmt.Formatter(log.NewColoredValue(t.Name(), log.Bold, log.FgRed)), slowFlush)
+			} else {
+				fmt.Fprintf(os.Stdout, "+++ %s ... still flushing after %v ...\n", t.Name(), slowFlush)
+			}
+		})
+		if err := queue.GetManager().FlushAll(context.Background(), -1); err != nil {
+			t.Errorf("Flushing queues failed with error %v", err)
+		}
+		timer.Stop()
+		flushTook := time.Since(start) - took
+		if flushTook > slowFlush {
+			if log.CanColorStdout {
+				fmt.Fprintf(os.Stdout, "+++ %s had a slow clean-up flush (took %v)\n", fmt.Formatter(log.NewColoredValue(t.Name(), log.Bold, log.FgRed)), fmt.Formatter(log.NewColoredValue(flushTook, log.Bold, log.FgRed)))
+			} else {
+				fmt.Fprintf(os.Stdout, "+++ %s had a slow clean-up flush (took %v)\n", t.Name(), flushTook)
+			}
+		}
+		_ = writerCloser.Close()
+	}
+}
+
+// Printf takes a format and args and prints the string to os.Stdout
+func Printf(format string, args ...interface{}) {
+	if log.CanColorStdout {
+		for i := 0; i < len(args); i++ {
+			args[i] = log.NewColoredValue(args[i])
+		}
+	}
+	fmt.Fprintf(os.Stdout, "\t"+format, args...)
+}
+
+// NewTestLogger creates a TestLogger as a log.LoggerProvider
+func NewTestLogger() log.LoggerProvider {
+	logger := &TestLogger{}
+	logger.Colorize = log.CanColorStdout
+	logger.Level = log.TRACE
+	return logger
+}
+
+// Init inits connection writer with json config.
+// json config only need key "level".
+func (log *TestLogger) Init(config string) error {
+	json := jsoniter.ConfigCompatibleWithStandardLibrary
+	err := json.Unmarshal([]byte(config), log)
+	if err != nil {
+		return err
+	}
+	log.NewWriterLogger(writerCloser)
+	return nil
+}
+
+// Flush when log should be flushed
+func (log *TestLogger) Flush() {
+}
+
+//ReleaseReopen does nothing
+func (log *TestLogger) ReleaseReopen() error {
+	return nil
+}
+
+// GetName returns the default name for this implementation
+func (log *TestLogger) GetName() string {
+	return "test"
+}
+
+func init() {
+	log.Register("test", NewTestLogger)
+	_, filename, _, _ := runtime.Caller(0)
+	prefix = strings.TrimSuffix(filename, "integrations/testlogger.go")
+}

models/migrations/v176.go

@@ -8,6 +8,9 @@ import (
 	"xorm.io/xorm"
 )
 
+// removeInvalidLabels looks through the database to look for comments and issue_labels
+// that refer to labels do not belong to the repository or organization that repository
+// that the issue is in
 func removeInvalidLabels(x *xorm.Engine) error {
 	type Comment struct {
 		ID      int64 `xorm:"pk autoincr"`

models/migrations/v176_test.go

@@ -0,0 +1,128 @@
+// Copyright 2021 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package migrations
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func Test_removeInvalidLabels(t *testing.T) {
+	// Models used by the migration
+	type Comment struct {
+		ID           int64 `xorm:"pk autoincr"`
+		Type         int   `xorm:"INDEX"`
+		IssueID      int64 `xorm:"INDEX"`
+		LabelID      int64
+		ShouldRemain bool // <- Flag for testing the migration
+	}
+
+	type Issue struct {
+		ID     int64 `xorm:"pk autoincr"`
+		RepoID int64 `xorm:"INDEX UNIQUE(repo_index)"`
+		Index  int64 `xorm:"UNIQUE(repo_index)"` // Index in one repository.
+	}
+
+	type Repository struct {
+		ID        int64  `xorm:"pk autoincr"`
+		OwnerID   int64  `xorm:"UNIQUE(s) index"`
+		LowerName string `xorm:"UNIQUE(s) INDEX NOT NULL"`
+	}
+
+	type Label struct {
+		ID     int64 `xorm:"pk autoincr"`
+		RepoID int64 `xorm:"INDEX"`
+		OrgID  int64 `xorm:"INDEX"`
+	}
+
+	type IssueLabel struct {
+		ID           int64 `xorm:"pk autoincr"`
+		IssueID      int64 `xorm:"UNIQUE(s)"`
+		LabelID      int64 `xorm:"UNIQUE(s)"`
+		ShouldRemain bool  // <- Flag for testing the migration
+	}
+
+	// load and prepare the test database
+	x, deferable := prepareTestEnv(t, 0, new(Comment), new(Issue), new(Repository), new(IssueLabel), new(Label))
+	if x == nil || t.Failed() {
+		defer deferable()
+		return
+	}
+	defer deferable()
+
+	var issueLabels []*IssueLabel
+	ilPreMigration := map[int64]*IssueLabel{}
+	ilPostMigration := map[int64]*IssueLabel{}
+
+	var comments []*Comment
+	comPreMigration := map[int64]*Comment{}
+	comPostMigration := map[int64]*Comment{}
+
+	// Get pre migration values
+	if err := x.Find(&issueLabels); err != nil {
+		t.Errorf("Unable to find issueLabels: %v", err)
+		return
+	}
+	for _, issueLabel := range issueLabels {
+		ilPreMigration[issueLabel.ID] = issueLabel
+	}
+	if err := x.Find(&comments); err != nil {
+		t.Errorf("Unable to find comments: %v", err)
+		return
+	}
+	for _, comment := range comments {
+		comPreMigration[comment.ID] = comment
+	}
+
+	// Run the migration
+	if err := removeInvalidLabels(x); err != nil {
+		t.Errorf("unable to RemoveInvalidLabels: %v", err)
+	}
+
+	// Get the post migration values
+	issueLabels = issueLabels[:0]
+	if err := x.Find(&issueLabels); err != nil {
+		t.Errorf("Unable to find issueLabels: %v", err)
+		return
+	}
+	for _, issueLabel := range issueLabels {
+		ilPostMigration[issueLabel.ID] = issueLabel
+	}
+	comments = comments[:0]
+	if err := x.Find(&comments); err != nil {
+		t.Errorf("Unable to find comments: %v", err)
+		return
+	}
+	for _, comment := range comments {
+		comPostMigration[comment.ID] = comment
+	}
+
+	// Finally test results of the migration
+	for id, comment := range comPreMigration {
+		post, ok := comPostMigration[id]
+		if ok {
+			if !comment.ShouldRemain {
+				t.Errorf("Comment[%d] remained but should have been deleted", id)
+			}
+			assert.Equal(t, comment, post)
+		} else if comment.ShouldRemain {
+			t.Errorf("Comment[%d] was deleted but should have remained", id)
+		}
+	}
+
+	for id, il := range ilPreMigration {
+		post, ok := ilPostMigration[id]
+		if ok {
+			if !il.ShouldRemain {
+				t.Errorf("IssueLabel[%d] remained but should have been deleted", id)
+			}
+			assert.Equal(t, il, post)
+		} else if il.ShouldRemain {
+			t.Errorf("IssueLabel[%d] was deleted but should have remained", id)
+		}
+	}
+
+}

models/migrations/v177.go

@@ -10,6 +10,7 @@ import (
 	"xorm.io/xorm"
 )
 
+// deleteOrphanedIssueLabels looks through the database for issue_labels where the label no longer exists and deletes them.
 func deleteOrphanedIssueLabels(x *xorm.Engine) error {
 	type IssueLabel struct {
 		ID      int64 `xorm:"pk autoincr"`

models/migrations/v177_test.go

@@ -0,0 +1,88 @@
+// Copyright 2021 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package migrations
+
+import (
+	"testing"
+
+	"code.gitea.io/gitea/modules/timeutil"
+	"github.com/stretchr/testify/assert"
+)
+
+func Test_deleteOrphanedIssueLabels(t *testing.T) {
+	// Create the models used in the migration
+	type IssueLabel struct {
+		ID      int64 `xorm:"pk autoincr"`
+		IssueID int64 `xorm:"UNIQUE(s)"`
+		LabelID int64 `xorm:"UNIQUE(s)"`
+	}
+
+	type Label struct {
+		ID              int64 `xorm:"pk autoincr"`
+		RepoID          int64 `xorm:"INDEX"`
+		OrgID           int64 `xorm:"INDEX"`
+		Name            string
+		Description     string
+		Color           string `xorm:"VARCHAR(7)"`
+		NumIssues       int
+		NumClosedIssues int
+		CreatedUnix     timeutil.TimeStamp `xorm:"INDEX created"`
+		UpdatedUnix     timeutil.TimeStamp `xorm:"INDEX updated"`
+	}
+
+	// Prepare and load the testing database
+	x, deferable := prepareTestEnv(t, 0, new(IssueLabel), new(Label))
+	if x == nil || t.Failed() {
+		defer deferable()
+		return
+	}
+	defer deferable()
+
+	var issueLabels []*IssueLabel
+	preMigration := map[int64]*IssueLabel{}
+	postMigration := map[int64]*IssueLabel{}
+
+	// Load issue labels that exist in the database pre-migration
+	if err := x.Find(&issueLabels); err != nil {
+		assert.NoError(t, err)
+		return
+	}
+	for _, issueLabel := range issueLabels {
+		preMigration[issueLabel.ID] = issueLabel
+	}
+
+	// Run the migration
+	if err := deleteOrphanedIssueLabels(x); err != nil {
+		assert.NoError(t, err)
+		return
+	}
+
+	// Load the remaining issue-labels
+	issueLabels = issueLabels[:0]
+	if err := x.Find(&issueLabels); err != nil {
+		assert.NoError(t, err)
+		return
+	}
+	for _, issueLabel := range issueLabels {
+		postMigration[issueLabel.ID] = issueLabel
+	}
+
+	// Now test what is left
+	if _, ok := postMigration[2]; ok {
+		t.Errorf("Orphaned Label[2] survived the migration")
+		return
+	}
+
+	if _, ok := postMigration[5]; ok {
+		t.Errorf("Orphaned Label[5] survived the migration")
+		return
+	}
+
+	for id, post := range postMigration {
+		pre := preMigration[id]
+		assert.Equal(t, pre, post, "migration changed issueLabel %d", id)
+	}
+
+}

models/models.go

@@ -142,7 +142,8 @@ func init() {
 	}
 }
 
-func getEngine() (*xorm.Engine, error) {
+// GetNewEngine returns a new xorm engine from the configuration
+func GetNewEngine() (*xorm.Engine, error) {
 	connStr, err := setting.DBConnStr()
 	if err != nil {
 		return nil, err
@@ -172,7 +173,7 @@ func getEngine() (*xorm.Engine, error) {
 
 // NewTestEngine sets a new test xorm.Engine
 func NewTestEngine() (err error) {
-	x, err = getEngine()
+	x, err = GetNewEngine()
 	if err != nil {
 		return fmt.Errorf("Connect to database: %v", err)
 	}
@@ -185,7 +186,7 @@ func NewTestEngine() (err error) {
 
 // SetEngine sets the xorm.Engine
 func SetEngine() (err error) {
-	x, err = getEngine()
+	x, err = GetNewEngine()
 	if err != nil {
 		return fmt.Errorf("Failed to connect to database: %v", err)
 	}

models/test_fixtures.go

@@ -10,16 +10,22 @@ import (
 	"time"
 
 	"github.com/go-testfixtures/testfixtures/v3"
+	"xorm.io/xorm"
 	"xorm.io/xorm/schemas"
 )
 
 var fixtures *testfixtures.Loader
 
 // InitFixtures initialize test fixtures for a test database
-func InitFixtures(dir string) (err error) {
+func InitFixtures(dir string, engine ...*xorm.Engine) (err error) {
+	e := x
+	if len(engine) == 1 {
+		e = engine[0]
+	}
+
 	testfiles := testfixtures.Directory(dir)
 	dialect := "unknown"
-	switch x.Dialect().URI().DBType {
+	switch e.Dialect().URI().DBType {
 	case schemas.POSTGRES:
 		dialect = "postgres"
 	case schemas.MYSQL:
@@ -33,13 +39,13 @@ func InitFixtures(dir string) (err error) {
 		os.Exit(1)
 	}
 	loaderOptions := []func(loader *testfixtures.Loader) error{
-		testfixtures.Database(x.DB().DB),
+		testfixtures.Database(e.DB().DB),
 		testfixtures.Dialect(dialect),
 		testfixtures.DangerousSkipTestDatabaseCheck(),
 		testfiles,
 	}
 
-	if x.Dialect().URI().DBType == schemas.POSTGRES {
+	if e.Dialect().URI().DBType == schemas.POSTGRES {
 		loaderOptions = append(loaderOptions, testfixtures.SkipResetSequences())
 	}
 
@@ -52,7 +58,11 @@ func InitFixtures(dir string) (err error) {
 }
 
 // LoadFixtures load fixtures for a test database
-func LoadFixtures() error {
+func LoadFixtures(engine ...*xorm.Engine) error {
+	e := x
+	if len(engine) == 1 {
+		e = engine[0]
+	}
 	var err error
 	// Database transaction conflicts could occur and result in ROLLBACK
 	// As a simple workaround, we just retry 20 times.
@@ -67,8 +77,8 @@ func LoadFixtures() error {
 		fmt.Printf("LoadFixtures failed after retries: %v\n", err)
 	}
 	// Now if we're running postgres we need to tell it to update the sequences
-	if x.Dialect().URI().DBType == schemas.POSTGRES {
+	if e.Dialect().URI().DBType == schemas.POSTGRES {
-		results, err := x.QueryString(`SELECT 'SELECT SETVAL(' ||
+		results, err := e.QueryString(`SELECT 'SELECT SETVAL(' ||
 		quote_literal(quote_ident(PGT.schemaname) || '.' || quote_ident(S.relname)) ||
 		', COALESCE(MAX(' ||quote_ident(C.attname)|| '), 1) ) FROM ' ||
 		quote_ident(PGT.schemaname)|| '.'||quote_ident(T.relname)|| ';'
@@ -90,7 +100,7 @@ func LoadFixtures() error {
 		}
 		for _, r := range results {
 			for _, value := range r {
-				_, err = x.Exec(value)
+				_, err = e.Exec(value)
 				if err != nil {
 					fmt.Printf("Failed to update sequence: %s Error: %v\n", value, err)
 					return err