Handle edge case and CI feedback

Author: kemzeb

routers/api/v1/repo/branch.go

@@ -410,6 +410,7 @@ func UpdateBranch(ctx *context.APIContext) {
 	//   in: path
 	//   description: name of the branch
 	//   type: string
+	//   required: true
 	// - name: body
 	//   in: body
 	//   schema:
@@ -460,6 +461,12 @@ func UpdateBranch(ctx *context.APIContext) {
 
 	branch, err := ctx.Repo.GitRepo.GetBranch(branchName)
 	if err != nil {
+		if git.IsErrBranchNotExist(err) {
+			// This could occur if the client passes a non-existent branch and we
+			// skip executing the branch that contains the RenameBranch() call.
+			ctx.NotFound(err)
+			return
+		}
 		ctx.Error(http.StatusInternalServerError, "GetBranch", err)
 		return
 	}

templates/swagger/v1_json.tmpl

@@ -219,6 +219,9 @@ func TestAPIUpdateBranch(t *testing.T) {
 			branchWasUnchanged := slices.ContainsFunc(branches, func(b *git_model.Branch) bool { return b.Name == "master" })
 			assert.True(t, branchWasUnchanged, "master branch shouldn't have been renamed")
 		})
+		t.Run("UpdateBranchWithNonExistentBranchAndNewNameIsTheEmptyString", func(t *testing.T) {
+			testAPIUpdateBranch(t, "user2", "repo1", "i-dont-exist", "", http.StatusNotFound)
+		})
 		t.Run("RenameBranchNormalScenario", func(t *testing.T) {
 			resp := testAPIUpdateBranch(t, "user2", "repo1", "branch2", "new-branch-name", http.StatusOK)
 			var branch api.Branch