4 files changed, 36 insertions(+), 19 deletions(-)

M api/graph/schema.graphqls
M api/graph/schema.resolvers.go
M gitsrht/blueprints/manage.py
M gitsrht/templates/settings_info.html

@@ 517,6 517,12 @@ input RepoInput {
   https://man.sr.ht/markdown/#post-processing
   """
   readme: String
+
+  """
+  Updates the repository HEAD reference, which serves as the default branch.
+  Must be a valid branch name.
+  """
+  HEAD: String
 }
 
 input UserWebhookInput {

@@ 387,6 387,29 @@ func (r *mutationResolver) UpdateRepository(ctx context.Context, id int, input m
 			return err
 		}
 
+		// This must be done after the query so that repo.Path is populated
+		valid.OptionalString("HEAD", func(ref string) {
+			gitRepo := repo.Repo()
+			gitRepo.Lock()
+			defer gitRepo.Unlock()
+			branchName := plumbing.NewBranchReferenceName(ref)
+			// Make sure that the branch exists
+			branch, err := gitRepo.Storer.Reference(branchName)
+			if err != nil {
+				valid.Error("%s", err.Error()).WithField("HEAD")
+				return
+			}
+			head := plumbing.NewSymbolicReference(plumbing.HEAD, branch.Name())
+			if err := gitRepo.Storer.SetReference(head); err != nil {
+				valid.Error("%s", err.Error()).WithField("HEAD")
+				return
+			}
+		})
+
+		if !valid.Ok() {
+			return errors.New("placeholder") // TODO: Avoid surfacing placeholder error
+		}
+
 		export := path.Join(repo.Path, "git-daemon-export-ok")
 		if repo.Visibility() == model.VisibilityPrivate {
 			err := os.Remove(export)

@@ 76,24 76,12 @@ def settings_info_POST(owner_name, repo_name):
     if isinstance(repo, BaseRedirectMixin):
         repo = repo.new_repo
 
-    # TODO: GraphQL mutation to set default branch name
     valid = Validation(request)
-    branch = valid.optional("default_branch_name")
-    if branch:
-        with GitRepository(repo.path) as git_repo:
-            new_default_branch = git_repo.branches.get(branch)
-            if new_default_branch:
-                head_ref = git_repo.lookup_reference("HEAD")
-                head_ref.set_target(new_default_branch.name)
-            else:
-                valid.error(f"Branch {branch} not found", field="default_branch_name")
-                return render_template("settings_info.html",
-                        owner=owner, repo=repo, **valid.kwargs)
 
     rewrite = lambda value: None if value == "" else value
     input = {
         key: rewrite(valid.source[key]) for key in [
-            "description", "visibility",
+            "description", "visibility", "HEAD",
         ] if valid.source.get(key) is not None
     }
 

@@ 77,16 77,16 @@
         </div>
       </fieldset>
       <div class="form-group">
-        <label for="default_branch_name">
+        <label for="HEAD">
           Default branch
         </label>
         <select
-          class="form-control {{valid.cls('default_branch_name')}}"
-          id="default_branch_name"
-          name="default_branch_name"
+          class="form-control {{valid.cls('HEAD')}}"
+          id="HEAD"
+          name="HEAD"
           {% if repo.git_repo.is_empty %}disabled{% endif %}
         >
-          {% set default_branch_name = repo.git_repo.default_branch_name() or "" %}
+          {% set default_branch_name = HEAD or repo.git_repo.default_branch_name() %}
           {% for branch in repo.git_repo.raw_listall_branches() %}
             {% set branch = branch.decode("utf-8", "replace") %}
             <option


@@ 98,7 98,7 @@
             <option>No branches</option>
           {% endfor %}
         </select>
-        {{valid.summary('default_branch_name')}}
+        {{valid.summary('HEAD')}}
       </div>
       <button type="submit" class="btn btn-primary pull-right">
         Save {{icon("caret-right")}}