add should_remove_source_branch query param to '/merge' request

Author: Ender Tunc

modules/core/src/main/scala/org/scalasteward/core/forge/gitlab/GitLabApiAlg.scala

@@ -238,7 +238,7 @@ final class GitLabApiAlg[F[_]: Parallel](
           res <-
             client
               .put[MergeRequestOut](
-                url.mergeWhenPiplineSucceeds(repo, mr.iid),
+                url.mergeWhenPiplineSucceeds(repo, mr.iid, gitLabCfg.removeSourceBranch),
                 modify(repo)
               )
               // it's possible that our status changed from can be merged already,

modules/core/src/main/scala/org/scalasteward/core/forge/gitlab/Url.scala

@@ -39,9 +39,17 @@ class Url(apiHost: Uri) {
   def existingMergeRequest(repo: Repo, number: PullRequestNumber): Uri =
     mergeRequest(repo) / number.toString
 
-  def mergeWhenPiplineSucceeds(repo: Repo, number: PullRequestNumber): Uri =
+  def mergeWhenPiplineSucceeds(
+      repo: Repo,
+      number: PullRequestNumber,
+      removeSourceBranch: Boolean
+  ): Uri =
     (existingMergeRequest(repo, number) / "merge")
       .withQueryParam("merge_when_pipeline_succeeds", "true")
+      .withOptionQueryParam(
+        "should_remove_source_branch",
+        Option.when(removeSourceBranch)(removeSourceBranch)
+      )
 
   def requiredApprovals(repo: Repo, number: PullRequestNumber, approvalsRequired: Int): Uri =
     (existingMergeRequest(repo, number) / "approvals")

modules/core/src/test/scala/org/scalasteward/core/forge/gitlab/GitLabApiAlgTest.scala

@@ -31,6 +31,9 @@ class GitLabApiAlgTest extends CatsEffectSuite with Http4sDsl[MockEff] {
   object MergeWhenPipelineSucceedsMatcher
       extends QueryParamDecoderMatcher[Boolean]("merge_when_pipeline_succeeds")
 
+  object ShouldRemoveSourceBranchMatcher
+      extends QueryParamDecoderMatcher[Boolean]("should_remove_source_branch")
+
   object RequiredReviewersMatcher extends QueryParamDecoderMatcher[Int]("approvals_required")
 
   object UsernameMatcher extends QueryParamDecoderMatcher[String]("username")
@@ -88,7 +91,7 @@ class GitLabApiAlgTest extends CatsEffectSuite with Http4sDsl[MockEff] {
       )
 
     case PUT -> Root / "projects" / "foo/bar" / "merge_requests" / "150" / "merge"
-        :? MergeWhenPipelineSucceedsMatcher(_) =>
+        :? MergeWhenPipelineSucceedsMatcher(_) +& ShouldRemoveSourceBranchMatcher(_) =>
       Ok(
         getMr.deepMerge(
           json""" { "iid": 150, "web_url": "https://gitlab.com/foo/bar/merge_requests/150" } """
@@ -140,12 +143,12 @@ class GitLabApiAlgTest extends CatsEffectSuite with Http4sDsl[MockEff] {
     user
   )
 
-  private val gitlabApiAlgAutoMerge = ForgeSelection.forgeApiAlg[MockEff](
+  private val gitlabApiAlgAutoMergeAndRemoveSourceBranch = ForgeSelection.forgeApiAlg[MockEff](
     config.forgeCfg.copy(tpe = ForgeType.GitLab, doNotFork = true),
     GitLabCfg(
       mergeWhenPipelineSucceeds = true,
       requiredReviewers = None,
-      removeSourceBranch = false
+      removeSourceBranch = true
     ),
     user
   )
@@ -267,8 +270,8 @@ class GitLabApiAlgTest extends CatsEffectSuite with Http4sDsl[MockEff] {
     assertIO(prOut, expected)
   }
 
-  test("createPullRequest -- auto merge") {
-    val prOut = gitlabApiAlgAutoMerge
+  test("createPullRequest -- auto merge and remove source branch") {
+    val prOut = gitlabApiAlgAutoMergeAndRemoveSourceBranch
       .createPullRequest(Repo("foo", "bar"), newPRData)
       .runA(state)