diff --git a/src/test/scala/gitbucket/core/service/AccessTokenServiceSpec.scala b/src/test/scala/gitbucket/core/service/AccessTokenServiceSpec.scala
index 56c7ce7a7..080a75603 100644
--- a/src/test/scala/gitbucket/core/service/AccessTokenServiceSpec.scala
+++ b/src/test/scala/gitbucket/core/service/AccessTokenServiceSpec.scala
@@ -1,9 +1,9 @@
 package gitbucket.core.service
 
-import gitbucket.core.model._
+import gitbucket.core.model.*
 import org.scalatest.funsuite.AnyFunSuite
-import gitbucket.core.model.Profile._
-import gitbucket.core.model.Profile.profile.blockingApi._
+import gitbucket.core.model.Profile.*
+import gitbucket.core.model.Profile.profile.blockingApi.*
 
 class AccessTokenServiceSpec extends AnyFunSuite with ServiceSpecBase {
 
diff --git a/src/test/scala/gitbucket/core/service/CommitStatusServiceSpec.scala b/src/test/scala/gitbucket/core/service/CommitStatusServiceSpec.scala
index 3ead4be55..d37e67208 100644
--- a/src/test/scala/gitbucket/core/service/CommitStatusServiceSpec.scala
+++ b/src/test/scala/gitbucket/core/service/CommitStatusServiceSpec.scala
@@ -1,8 +1,9 @@
 package gitbucket.core.service
 
-import gitbucket.core.model._
-import gitbucket.core.model.Profile._
-import gitbucket.core.model.Profile.profile.blockingApi._
+import gitbucket.core.model.*
+import gitbucket.core.model.Profile.*
+import gitbucket.core.model.Profile.profile.blockingApi.*
+import gitbucket.core.model.Session
 import org.scalatest.funsuite.AnyFunSuite
 
 class CommitStatusServiceSpec
@@ -12,7 +13,7 @@ class CommitStatusServiceSpec
     with RepositoryService
     with AccountService {
   val now = new java.util.Date()
-  val fixture1 = CommitStatus(
+  val fixture1: CommitStatus = CommitStatus(
     userName = "root",
     repositoryName = "repo",
     commitId = "0e97b8f59f7cdd709418bb59de53f741fd1c1bd7",
@@ -24,8 +25,9 @@ class CommitStatusServiceSpec
     updatedDate = now,
     registeredDate = now
   )
-  def findById(id: Int)(implicit s: Session) = CommitStatuses.filter(_.byPrimaryKey(id)).firstOption
-  def generateFixture1(tester: Account)(implicit s: Session) =
+  def findById(id: Int)(implicit s: Session): Option[CommitStatus] =
+    CommitStatuses.filter(_.byPrimaryKey(id)).firstOption
+  def generateFixture1(tester: Account)(implicit s: Session): Int =
     createCommitStatus(
       userName = fixture1.userName,
       repositoryName = fixture1.repositoryName,
diff --git a/src/test/scala/gitbucket/core/service/LabelsServiceSpec.scala b/src/test/scala/gitbucket/core/service/LabelsServiceSpec.scala
index 4b708b623..4c4164c37 100644
--- a/src/test/scala/gitbucket/core/service/LabelsServiceSpec.scala
+++ b/src/test/scala/gitbucket/core/service/LabelsServiceSpec.scala
@@ -1,6 +1,6 @@
 package gitbucket.core.service
 
-import gitbucket.core.model._
+import gitbucket.core.model.*
 import org.scalatest.funspec.AnyFunSpec
 
 class LabelsServiceSpec extends AnyFunSpec with ServiceSpecBase {
diff --git a/src/test/scala/gitbucket/core/service/MergeServiceSpec.scala b/src/test/scala/gitbucket/core/service/MergeServiceSpec.scala
index 220e7f5aa..099998cb4 100644
--- a/src/test/scala/gitbucket/core/service/MergeServiceSpec.scala
+++ b/src/test/scala/gitbucket/core/service/MergeServiceSpec.scala
@@ -1,31 +1,32 @@
 package gitbucket.core.service
 
 import org.eclipse.jgit.api.Git
-import org.eclipse.jgit.revwalk._
+import org.eclipse.jgit.revwalk.*
 import org.eclipse.jetty.server.handler.AbstractHandler
 import org.scalatest.funspec.AnyFunSpec
+
 import java.io.File
 import java.util.Date
 import java.net.InetSocketAddress
 import java.nio.charset.StandardCharsets
-
 import javax.servlet.http.{HttpServletRequest, HttpServletResponse}
-
 import scala.util.Using
-import scala.jdk.CollectionConverters._
+import scala.jdk.CollectionConverters.*
 import gitbucket.core.controller.Context
 import gitbucket.core.plugin.ReceiveHook
-import gitbucket.core.util.Directory._
-import gitbucket.core.util.GitSpecUtil._
+import gitbucket.core.util.Directory.*
+import gitbucket.core.util.GitSpecUtil.*
 import gitbucket.core.service.RepositoryService.RepositoryInfo
-import gitbucket.core.model._
-import gitbucket.core.model.Profile._
-import gitbucket.core.model.Profile.profile.blockingApi._
+import gitbucket.core.model.*
+import gitbucket.core.model.Profile.*
+import gitbucket.core.model.Profile.profile.blockingApi.*
+import gitbucket.core.model.Session
 import org.eclipse.jetty.webapp.WebAppContext
 import org.eclipse.jetty.server.{Request, Server}
-import org.json4s.jackson.JsonMethods._
-import org.json4s.jvalue2monadic
-import MergeServiceSpec._
+import org.json4s.jackson.JsonMethods.*
+import org.json4s.{Formats, jvalue2monadic}
+import MergeServiceSpec.*
+import org.eclipse.jgit.lib.ObjectId
 import org.json4s.JsonAST.{JArray, JString}
 
 class MergeServiceSpec extends AnyFunSpec with ServiceSpecBase {
@@ -54,7 +55,7 @@ class MergeServiceSpec extends AnyFunSpec with ServiceSpecBase {
     }
     dir
   }
-  def createConfrict(git: Git) = {
+  def createConfrict(git: Git): ObjectId = {
     createFile(git, s"refs/heads/${branch}", "test.txt", "hoge2")
     createFile(git, s"refs/pull/${issueId}/head", "test.txt", "hoge4")
   }
@@ -141,14 +142,14 @@ class MergeServiceSpec extends AnyFunSpec with ServiceSpecBase {
   }
   describe("mergePullRequest") {
     it("can merge") {
-      implicit val jsonFormats = gitbucket.core.api.JsonFormat.jsonFormats
-      import gitbucket.core.util.Implicits._
+      implicit val jsonFormats: Formats = gitbucket.core.api.JsonFormat.jsonFormats
+      import gitbucket.core.util.Implicits.*
 
       withTestDB { implicit session =>
         generateNewUserWithDBRepository("user1", "repo8")
         initRepository("user1", "repo8")
 
-        implicit val context = Context(
+        implicit val context: Context = Context(
           createSystemSettings(),
           Some(createAccount("dummy2", "dummy2-fullname", "dummy2@example.com")),
           request
diff --git a/src/test/scala/gitbucket/core/service/ProtectedBranchServiceSpec.scala b/src/test/scala/gitbucket/core/service/ProtectedBranchServiceSpec.scala
index 7b72b9794..80a1c5691 100644
--- a/src/test/scala/gitbucket/core/service/ProtectedBranchServiceSpec.scala
+++ b/src/test/scala/gitbucket/core/service/ProtectedBranchServiceSpec.scala
@@ -1,6 +1,6 @@
 package gitbucket.core.service
 
-import gitbucket.core.util.GitSpecUtil._
+import gitbucket.core.util.GitSpecUtil.*
 import org.eclipse.jgit.transport.{ReceivePack, ReceiveCommand}
 import org.eclipse.jgit.lib.ObjectId
 import gitbucket.core.model.CommitState
diff --git a/src/test/scala/gitbucket/core/service/PullRequestServiceSpec.scala b/src/test/scala/gitbucket/core/service/PullRequestServiceSpec.scala
index c57e5b319..a7abde76c 100644
--- a/src/test/scala/gitbucket/core/service/PullRequestServiceSpec.scala
+++ b/src/test/scala/gitbucket/core/service/PullRequestServiceSpec.scala
@@ -1,6 +1,6 @@
 package gitbucket.core.service
 
-import gitbucket.core.model._
+import gitbucket.core.model.*
 import org.scalatest.funspec.AnyFunSpec
 
 class PullRequestServiceSpec
diff --git a/src/test/scala/gitbucket/core/service/RepositoryServiceSpec.scala b/src/test/scala/gitbucket/core/service/RepositoryServiceSpec.scala
index c600b8d5e..1b3b9df77 100644
--- a/src/test/scala/gitbucket/core/service/RepositoryServiceSpec.scala
+++ b/src/test/scala/gitbucket/core/service/RepositoryServiceSpec.scala
@@ -1,6 +1,6 @@
 package gitbucket.core.service
 
-import gitbucket.core.model._
+import gitbucket.core.model.*
 import org.scalatest.funsuite.AnyFunSuite
 
 class RepositoryServiceSpec extends AnyFunSuite with ServiceSpecBase with RepositoryService with AccountService {
diff --git a/src/test/scala/gitbucket/core/service/ServiceSpecBase.scala b/src/test/scala/gitbucket/core/service/ServiceSpecBase.scala
index 7a9345154..340da6803 100644
--- a/src/test/scala/gitbucket/core/service/ServiceSpecBase.scala
+++ b/src/test/scala/gitbucket/core/service/ServiceSpecBase.scala
@@ -5,8 +5,9 @@ import gitbucket.core.util.{DatabaseConfig, Directory, FileUtil, JGitUtil}
 import io.github.gitbucket.solidbase.Solidbase
 import liquibase.database.core.H2Database
 import liquibase.database.jvm.JdbcConnection
-import gitbucket.core.model._
-import gitbucket.core.model.Profile.profile.blockingApi._
+import gitbucket.core.model.*
+import gitbucket.core.model.Profile.profile.blockingApi.*
+import gitbucket.core.model.Session
 import org.apache.commons.io.FileUtils
 
 import java.sql.DriverManager
@@ -21,21 +22,21 @@ import gitbucket.core.service.SystemSettingsService.{
 }
 
 import javax.servlet.http.{HttpServletRequest, HttpSession}
-import org.mockito.Mockito._
+import org.mockito.Mockito.*
 
 import scala.util.Random
 import scala.util.Using
 
 trait ServiceSpecBase {
 
-  val request = mock(classOf[HttpServletRequest])
-  val session = mock(classOf[HttpSession])
+  val request: HttpServletRequest = mock(classOf[HttpServletRequest])
+  val session: HttpSession = mock(classOf[HttpSession])
   when(request.getRequestURL).thenReturn(new StringBuffer("http://localhost:8080/path.html"))
   when(request.getRequestURI).thenReturn("/path.html")
   when(request.getContextPath).thenReturn("")
   when(request.getSession).thenReturn(session)
 
-  def createSystemSettings() =
+  def createSystemSettings(): SystemSettings =
     SystemSettings(
       baseUrl = None,
       information = None,
diff --git a/src/test/scala/gitbucket/core/service/WebHookJsonFormatSpec.scala b/src/test/scala/gitbucket/core/service/WebHookJsonFormatSpec.scala
index 6a185f559..2a21a7126 100644
--- a/src/test/scala/gitbucket/core/service/WebHookJsonFormatSpec.scala
+++ b/src/test/scala/gitbucket/core/service/WebHookJsonFormatSpec.scala
@@ -1,12 +1,12 @@
 package gitbucket.core.service
 
 import gitbucket.core.api.JsonFormat
-import gitbucket.core.service.WebHookService._
+import gitbucket.core.service.WebHookService.*
 import org.scalatest.Assertion
 import org.scalatest.funsuite.AnyFunSuite
 
 class WebHookJsonFormatSpec extends AnyFunSuite {
-  import gitbucket.core.api.ApiSpecModels._
+  import gitbucket.core.api.ApiSpecModels.*
 
   private def assert(payload: WebHookPayload, expected: String): Assertion = {
     val json = JsonFormat(payload)
@@ -34,7 +34,7 @@ class WebHookJsonFormatSpec extends AnyFunSuite {
   }
 
   test("WebHookPushPayload") {
-    import gitbucket.core.util.GitSpecUtil._
+    import gitbucket.core.util.GitSpecUtil.*
     import org.eclipse.jgit.lib.{Constants, ObjectId}
 
     withTestRepository { git =>