#2505 Allow to fork and disallow to create PRs for mirrors.

models/repo.go

 
 // CanBeForked returns true if repository meets the requirements of being forked.
 func (repo *Repository) CanBeForked() bool {
-	return !repo.IsBare && !repo.IsMirror
+	return !repo.IsBare
+}
+
+// CanEnablePulls returns true if repository meets the requirements of accepting pulls.
+func (repo *Repository) CanEnablePulls() bool {
+	return !repo.IsMirror
+}
+
+// AllowPulls returns true if repository meets the requirements of accepting pulls and has them enabled.
+func (repo *Repository) AllowsPulls() bool {
+	return repo.CanEnablePulls() && repo.EnablePulls;
 }
 
 func (repo *Repository) NextIssueIndex() int64 {

modules/middleware/repo.go

 		ctx.Data["IsRepositoryOwner"] = ctx.Repo.IsOwner()
 		ctx.Data["IsRepositoryAdmin"] = ctx.Repo.IsAdmin()
 		ctx.Data["IsRepositoryPusher"] = ctx.Repo.IsPusher()
-		ctx.Data["CanPullRequest"] = ctx.Repo.IsAdmin() && repo.BaseRepo != nil && repo.BaseRepo.EnablePulls
+		ctx.Data["CanPullRequest"] = ctx.Repo.IsAdmin() && repo.BaseRepo != nil && repo.BaseRepo.AllowsPulls()
 
 		ctx.Data["DisableSSH"] = setting.DisableSSH
 		ctx.Data["CloneLink"] = repo.CloneLink()

routers/repo/issue.go

 }
 
 func MustEnablePulls(ctx *middleware.Context) {
-	if !ctx.Repo.Repository.EnablePulls {
+	if !ctx.Repo.Repository.CanEnablePulls() {
+		ctx.Handle(404, "Unsupported", nil)
+	} else if !ctx.Repo.Repository.EnablePulls {
 		ctx.Handle(404, "MustEnablePulls", nil)
 	}
 

templates/repo/header.tmpl

 					<i class="icon octicon octicon-issue-opened"></i> {{.i18n.Tr "repo.issues"}} <span class="ui {{if not .Repository.NumOpenIssues}}gray{{else}}blue{{end}} small label">{{.Repository.NumOpenIssues}}</span>
 				</a>
 			{{end}}
-			{{if .Repository.EnablePulls}}
+			{{if .Repository.AllowsPulls}}
 				<a class="{{if .PageIsPullList}}active{{end}} item" href="{{.RepoLink}}/pulls">
 					<i class="icon octicon octicon-git-pull-request"></i> {{.i18n.Tr "repo.pulls"}} <span class="ui {{if not .Repository.NumOpenPulls}}gray{{else}}blue{{end}} small label">{{.Repository.NumOpenPulls}}</span>
 				</a>

templates/repo/settings/options.tmpl

 							<p class="help">{{.i18n.Tr "repo.settings.tracker_url_format_desc" | Str2html}}</p>
 						</div>
 
-						<div class="ui divider"></div>
+						{{if .Repository.CanEnablePulls}}
+							<div class="ui divider"></div>
 
-						<div class="inline field">
-							<label>{{.i18n.Tr "repo.pulls"}}</label>
-							<div class="ui checkbox">
-								<input name="enable_pulls" type="checkbox" {{if .Repository.EnablePulls}}checked{{end}}>
-								<label>{{.i18n.Tr "repo.settings.pulls_desc"}}</label>
+							<div class="inline field">
+								<label>{{.i18n.Tr "repo.pulls"}}</label>
+								<div class="ui checkbox">
+									<input name="enable_pulls" type="checkbox" {{if .Repository.EnablePulls}}checked{{end}}>
+									<label>{{.i18n.Tr "repo.settings.pulls_desc"}}</label>
+								</div>
 							</div>
-						</div>
+						{{end}}
 
 						<div class="ui divider"></div>
 						<div class="field">