Slice 3: the PR flow

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

frontend/src/components/RFCView.jsx

@@ -38,6 +38,7 @@ import PromptBar from './PromptBar.jsx'
 import ChatPanel from './ChatPanel.jsx'
 import ChangePanel from './ChangePanel.jsx'
 import DiffView from './DiffView.jsx'
+import PRModal from './PRModal.jsx'
 
 const MANUAL_IDLE_MS = 5 * 60 * 1000   // §8.6 idle window; exact value is impl detail.
 const MANUAL_DEBOUNCE_MS = 800
@@ -82,6 +83,7 @@ export default function RFCView({ viewer }) {
   const [isStreaming, setIsStreaming] = useState(false)
   const [focusedChangeId, setFocusedChangeId] = useState(null)
   const [showVisibility, setShowVisibility] = useState(false)
+  const [showPRModal, setShowPRModal] = useState(false)
 
   // Manual-edit buffer state per §8.11.
   const [manualPending, setManualPending] = useState(null)
@@ -451,6 +453,17 @@ export default function RFCView({ viewer }) {
   const inDiscuss = mode === 'discuss'
   const pendingCount = changes.filter(c => c.state === 'pending').length
 
+  // §10.1: the Open PR affordance only surfaces on a non-main branch
+  // that has commits ahead of main and no open PR already.
+  const openPRForBranch = mainView?.open_prs?.find(p => p.head_branch === branchParam) || null
+  const branchHasCommitsAhead = branchView && mainView && branchView.body !== (mainView.body || '')
+  const canOpenPR = (
+    branchParam !== 'main'
+    && canContribute
+    && !openPRForBranch
+    && branchHasCommitsAhead
+  )
+
   return (
     <div className="rfc-view">
       {/* Breadcrumb */}
@@ -493,6 +506,25 @@ export default function RFCView({ viewer }) {
           {!viewer && (
             <a className="btn-link" href="/auth/login">Sign in</a>
           )}
+          {canOpenPR && (
+            <button
+              type="button"
+              className="btn-primary btn-open-pr"
+              onClick={() => setShowPRModal(true)}
+              title="§10.1 — open a PR from this branch against main"
+            >
+              Open PR
+            </button>
+          )}
+          {openPRForBranch && (
+            <a
+              className="btn-link"
+              href={`/rfc/${slug}/pr/${openPRForBranch.pr_number}`}
+              title="View the open PR for this branch"
+            >
+              PR #{openPRForBranch.pr_number} →
+            </a>
+          )}
           {canChangeSettings && branchParam !== 'main' && (
             <button
               type="button"
@@ -627,6 +659,19 @@ export default function RFCView({ viewer }) {
         </div>
       </div>
 
+      {showPRModal && (
+        <PRModal
+          slug={slug}
+          branch={branchParam}
+          branchIsPrivate={!branchView.visibility?.read_public}
+          onClose={() => setShowPRModal(false)}
+          onOpened={(prNumber) => {
+            setShowPRModal(false)
+            navigate(`/rfc/${slug}/pr/${prNumber}`)
+          }}
+        />
+      )}
+
       {showVisibility && (
         <BranchVisibilityModal
           slug={slug}