Merge setting.InitXXX into one function with options (#24389)

This PR will merge 3 Init functions on setting packages as 1 and
introduce an options struct.

models/unittest/testdb.go

@@ -6,12 +6,15 @@ package unittest
 import (
 	"context"
 	"fmt"
+	"log"
 	"os"
 	"path/filepath"
+	"strings"
 	"testing"
 
 	"code.gitea.io/gitea/models/db"
 	system_model "code.gitea.io/gitea/models/system"
+	"code.gitea.io/gitea/modules/auth/password/hash"
 	"code.gitea.io/gitea/modules/base"
 	"code.gitea.io/gitea/modules/git"
 	"code.gitea.io/gitea/modules/setting"
@@ -39,6 +42,22 @@ func fatalTestError(fmtStr string, args ...interface{}) {
 	os.Exit(1)
 }
 
+// InitSettings initializes config provider and load common setttings for tests
+func InitSettings(extraConfigs ...string) {
+	setting.Init(&setting.Options{
+		AllowEmpty:  true,
+		ExtraConfig: strings.Join(extraConfigs, "\n"),
+	})
+
+	if err := setting.PrepareAppDataPath(); err != nil {
+		log.Fatalf("Can not prepare APP_DATA_PATH: %v", err)
+	}
+	// register the dummy hash algorithm function used in the test fixtures
+	_ = hash.Register("dummy", hash.NewDummyHasher)
+
+	setting.PasswordHashAlgo, _ = hash.SetDefaultPasswordHashAlgorithm("dummy")
+}
+
 // TestOptions represents test options
 type TestOptions struct {
 	GiteaRootPath string
@@ -50,6 +69,9 @@ type TestOptions struct {
 // MainTest a reusable TestMain(..) function for unit tests that need to use a
 // test database. Creates the test database, and sets necessary settings.
 func MainTest(m *testing.M, testOpts *TestOptions) {
+	setting.SetCustomPathAndConf("", "", "")
+	InitSettings()
+
 	var err error
 
 	giteaRoot = testOpts.GiteaRootPath