feat: add repo setting to not pre-populate target branch in PR

rhodecode/apps/repository/views/repo_pull_requests.py

@@ -907,6 +907,7 @@ class RepoPullRequestsView(RepoAppView, DataGridAppView):
                 branch=branch_ref,
                 bookmark=bookmark_ref,
                 translator=self.request.translate,
+                prepopulate_branch=True,  # Always pre-populate for source repo
             )
         except CommitDoesNotExistError as e:
             log.exception(e)
@@ -921,7 +922,14 @@ class RepoPullRequestsView(RepoAppView, DataGridAppView):
                 # change default if we have a parent repo
                 default_target_repo = source_repo.parent
 
-        target_repo_data = PullRequestModel().generate_repo_data(default_target_repo, translator=self.request.translate)
+        # Get the target branch pre-population setting
+        prepopulate_target_branch = self._get_repo_setting(
+            default_target_repo, "rhodecode_pr_target_branch_prepopulate", True
+        )
+
+        target_repo_data = PullRequestModel().generate_repo_data(
+            default_target_repo, translator=self.request.translate, prepopulate_branch=prepopulate_target_branch
+        )
 
         selected_source_ref = source_repo_data["refs"]["selected_ref"]
         title_source_ref = ""
@@ -936,6 +944,7 @@ class RepoPullRequestsView(RepoAppView, DataGridAppView):
             "source_refs_json": ext_json.str_json(source_repo_data),
             "target_repo_name": default_target_repo.repo_name,
             "target_refs_json": ext_json.str_json(target_repo_data),
+            "pr_target_branch_prepopulate": prepopulate_target_branch,
         }
         c.default_source_ref = selected_source_ref
 
@@ -958,7 +967,12 @@ class RepoPullRequestsView(RepoAppView, DataGridAppView):
         if not target_perm:
             raise HTTPNotFound()
 
-        return PullRequestModel().generate_repo_data(repo, translator=self.request.translate)
+        # Get the target branch pre-population setting for the target repo
+        prepopulate_target_branch = self._get_repo_setting(repo, "pr_target_branch_prepopulate", True)
+
+        return PullRequestModel().generate_repo_data(
+            repo, translator=self.request.translate, prepopulate_branch=prepopulate_target_branch
+        )
 
     @LoginRequired()
     @NotAnonymous()

rhodecode/model/forms.py

@@ -453,6 +453,9 @@ class _BaseVcsSettingsForm(formencode.Schema):
     # cache
     rhodecode_diff_cache = v.StringBoolean(if_missing=False)
 
+    # Pull Request settings
+    pr_target_branch_prepopulate = v.StringBoolean(if_missing=True)
+
 
 def ApplicationUiSettingsForm(localizer):
     _ = localizer

rhodecode/model/pull_request.py

@@ -2053,13 +2053,19 @@ class PullRequestModel(BaseModel):
         workspace_id = "pr-%s" % pull_request.pull_request_id
         return workspace_id
 
-    def generate_repo_data(self, repo, commit_id=None, branch=None, bookmark=None, translator=None):
+    def generate_repo_data(
+        self, repo, commit_id=None, branch=None, bookmark=None, translator=None, prepopulate_branch=True
+    ):
         from rhodecode.model.repo import RepoModel
 
         all_refs, selected_ref = self._get_repo_pullrequest_sources(
             repo.scm_instance(), commit_id=commit_id, branch=branch, bookmark=bookmark, translator=translator
         )
 
+        # If branch pre-population is disabled, don't auto-select any branch
+        if not prepopulate_branch:
+            selected_ref = None
+
         refs_select2 = []
         for element in all_refs:
             children = [{"id": x[0], "text": x[1]} for x in element[0]]

rhodecode/model/settings.py

@@ -457,6 +457,7 @@ class VcsSettingsModel(object):
         "git_close_branch_before_merging",
         "git_merge_strategy_selector",
         "diff_cache",
+        "pr_target_branch_prepopulate",
     )
 
     HOOKS_SETTINGS = (

rhodecode/templates/base/vcs_settings.mako

@@ -234,6 +234,14 @@
                 <div class="label">
                     <span class="help-block">${_('During the update of a pull request, the position of inline comments will be updated and outdated inline comments will be hidden.')}</span>
                 </div>
+                
+                <div class="checkbox">
+                    ${h.checkbox('pr_target_branch_prepopulate' + suffix, 'True', **kwargs)}
+                    <label for="pr_target_branch_prepopulate${suffix}">${_('Pre-populate target branch when creating pull requests')}</label>
+                </div>
+                <div class="label">
+                    <span class="help-block">${_('When enabled, the target branch field will be automatically populated when creating pull requests. Disable this to prevent expensive diff calculations on repositories with many divergent branches.')}</span>
+                </div>
             </div>
         </div>
     % endif

rhodecode/templates/pullrequests/pullrequest.mako

@@ -245,6 +245,7 @@
    var defaultSourceRepoData = ${c.default_repo_data['source_refs_json']|n};
    var defaultTargetRepo = '${c.default_repo_data['target_repo_name']}';
    var defaultTargetRepoData = ${c.default_repo_data['target_refs_json']|n};
+   var prTargetBranchPrepopulate = ${'true' if c.default_repo_data['pr_target_branch_prepopulate'] else 'false'};
 
    var $pullRequestForm = $('#pull_request_form');
    var $pullRequestSubmit = $('#pr_submit', $pullRequestForm);
@@ -530,8 +531,9 @@
        $('#switch_base').html("<a class=\"tooltip\" title=\"{0}\" href=\"{1}\">Switch sides</a>".format(title, prLink))
 
        // generate dynamic select2 for refs.
-       initTargetRefs(repoData['refs']['select2_refs'],
-                      repoData['refs']['selected_ref']);
+       // Only pre-populate target branch if the setting allows it
+       var selectedRef = prTargetBranchPrepopulate ? repoData['refs']['selected_ref'] : null;
+       initTargetRefs(repoData['refs']['select2_refs'], selectedRef);
 
    };