feat: support creating worktrees from GitHub pull requests

packages/app/e2e/global-setup.ts

@@ -1,6 +1,6 @@
 import { spawn, type ChildProcess, execFileSync, execSync } from "node:child_process";
 import { existsSync } from "node:fs";
-import { mkdtemp, rm } from "node:fs/promises";
+import { chmod, mkdtemp, rm, writeFile } from "node:fs/promises";
 import { tmpdir } from "node:os";
 import path from "node:path";
 import net from "node:net";
@@ -182,6 +182,7 @@ async function isOpenAiApiKeyUsable(apiKey: string | undefined): Promise<boolean
 let daemonProcess: ChildProcess | null = null;
 let metroProcess: ChildProcess | null = null;
 let paseoHome: string | null = null;
+let fakeGhBinDir: string | null = null;
 let relayProcess: ChildProcess | null = null;
 
 type OfferPayload = {
@@ -191,6 +192,47 @@ type OfferPayload = {
   relay: { endpoint: string };
 };
 
+async function createFakeGhBin(): Promise<string> {
+  const binDir = await mkdtemp(path.join(tmpdir(), "paseo-e2e-gh-bin-"));
+  const ghPath = path.join(binDir, "gh");
+  await writeFile(
+    ghPath,
+    `#!/usr/bin/env node
+const args = process.argv.slice(2);
+
+if (args[0] === "auth" && args[1] === "status") {
+  process.exit(0);
+}
+
+if (args[0] === "pr" && args[1] === "list") {
+  console.log(JSON.stringify([
+    {
+      number: 515,
+      title: "Review selected start ref",
+      url: "https://github.com/getpaseo/paseo/pull/515",
+      state: "OPEN",
+      body: "Fixture pull request for app e2e.",
+      labels: [],
+      baseRefName: "main",
+      headRefName: "feature/start-from-pr"
+    }
+  ]));
+  process.exit(0);
+}
+
+if (args[0] === "issue" && args[1] === "list") {
+  console.log("[]");
+  process.exit(0);
+}
+
+console.error("Unsupported fake gh invocation: " + args.join(" "));
+process.exit(1);
+`,
+  );
+  await chmod(ghPath, 0o755);
+  return binDir;
+}
+
 function stripAnsi(input: string): string {
   return input.replace(/\u001b\[[0-9;]*m/g, "");
 }
@@ -281,6 +323,7 @@ export default async function globalSetup() {
   let relayPort = 0;
   const metroPort = await getAvailablePort();
   paseoHome = await mkdtemp(path.join(tmpdir(), "paseo-e2e-home-"));
+  fakeGhBinDir = await createFakeGhBin();
   let relayLineBuffer = createLineBuffer();
   const metroLineBuffer = createLineBuffer();
   const daemonLineBuffer = createLineBuffer();
@@ -298,6 +341,10 @@ export default async function globalSetup() {
       await rm(paseoHome, { recursive: true, force: true });
       paseoHome = null;
     }
+    if (fakeGhBinDir) {
+      await rm(fakeGhBinDir, { recursive: true, force: true });
+      fakeGhBinDir = null;
+    }
   };
 
   const openAiUsable = await isOpenAiApiKeyUsable(process.env.OPENAI_API_KEY);
@@ -482,6 +529,7 @@ export default async function globalSetup() {
       cwd: serverDir,
       env: {
         ...process.env,
+        PATH: `${fakeGhBinDir}${path.delimiter}${process.env.PATH ?? ""}`,
         PASEO_HOME: paseoHome,
         PASEO_SERVER_ID: "srv_e2e_test_daemon",
         PASEO_LISTEN: `0.0.0.0:${port}`,

packages/app/e2e/helpers/new-workspace.ts

@@ -153,7 +153,7 @@ export async function createWorktreeViaDaemon(
   };
 }
 
-export async function clickNewWorkspaceButton(
+export async function openNewWorkspaceComposer(
   page: Page,
   input: { projectKey: string; projectDisplayName: string },
 ): Promise<void> {
@@ -168,7 +168,13 @@ export async function clickNewWorkspaceButton(
   await expect(page).toHaveURL(/\/h\/[^/]+\/new(?:\?.*)?$/, {
     timeout: 30_000,
   });
+}
 
+export async function clickNewWorkspaceButton(
+  page: Page,
+  input: { projectKey: string; projectDisplayName: string },
+): Promise<void> {
+  await openNewWorkspaceComposer(page, input);
   const createButton = page
     .getByTestId("message-input-root")
     .getByRole("button", { name: "Create" });
@@ -176,6 +182,44 @@ export async function clickNewWorkspaceButton(
   await createButton.click();
 }
 
+export async function openStartingRefPicker(page: Page): Promise<void> {
+  const trigger = page.getByTestId("new-workspace-ref-picker-trigger");
+  await expect(trigger).toBeVisible({ timeout: 30_000 });
+  await trigger.click();
+}
+
+export async function selectBranchInPicker(page: Page, name: string): Promise<void> {
+  const branchRow = page.getByTestId(`new-workspace-ref-picker-branch-${name}`);
+  await expect(branchRow).toBeVisible({ timeout: 30_000 });
+  await branchRow.click();
+}
+
+export async function selectGitHubPrInPicker(page: Page, number: number): Promise<void> {
+  const prRow = page.getByTestId(`new-workspace-ref-picker-pr-${number}`);
+  await expect(prRow).toBeVisible({ timeout: 30_000 });
+  await prRow.click();
+}
+
+export async function expectStartingRefPickerTriggerPr(
+  page: Page,
+  input: { number: number; title: string; headRef: string },
+): Promise<void> {
+  const trigger = page.getByTestId("new-workspace-ref-picker-trigger");
+  await expect(trigger).toContainText(`#${input.number}`);
+  await expect(trigger).toContainText(input.title);
+  await expect(trigger).not.toContainText(input.headRef);
+}
+
+export async function expectComposerGithubAttachmentPill(
+  page: Page,
+  input: { number: number; title: string },
+): Promise<void> {
+  const pills = page.getByTestId("composer-github-attachment-pill");
+  await expect(pills).toHaveCount(1);
+  await expect(pills.first()).toContainText(`#${input.number}`);
+  await expect(pills.first()).toContainText(input.title);
+}
+
 export async function assertNewWorkspaceSidebarAndHeader(
   page: Page,
   input: { serverId: string; previousWorkspaceId: string; projectDisplayName: string },

packages/app/e2e/helpers/workspace.ts

@@ -5,6 +5,7 @@ import path from "node:path";
 
 type TempRepo = {
   path: string;
+  branchHeads: Record<string, string>;
   cleanup: () => Promise<void>;
 };
 
@@ -14,6 +15,7 @@ export const createTempGitRepo = async (
     withRemote?: boolean;
     paseoConfig?: Record<string, unknown>;
     files?: Array<{ path: string; content: string }>;
+    branches?: string[];
   },
 ): Promise<TempRepo> => {
   // Keep E2E repo paths short so terminal prompt + typed commands stay visible without zsh clipping.
@@ -47,19 +49,72 @@ export const createTempGitRepo = async (
   }
   execSync('git commit -m "Initial commit"', { cwd: repoPath, stdio: "ignore" });
 
+  const branchHeads: Record<string, string> = {};
+  const branches = Array.from(new Set(options?.branches ?? []));
+  for (const branch of branches) {
+    if (branch !== "main") {
+      execSync(`git checkout -b ${JSON.stringify(branch)} main`, {
+        cwd: repoPath,
+        stdio: "ignore",
+      });
+    }
+    const markerPath = `.paseo-e2e-${branch.replace(/[^a-zA-Z0-9._-]/g, "-")}.txt`;
+    await writeFile(path.join(repoPath, markerPath), `branch ${branch}\n`);
+    execSync(`git add ${JSON.stringify(markerPath)}`, { cwd: repoPath, stdio: "ignore" });
+    execSync(`git commit -m ${JSON.stringify(`Add ${branch} marker`)}`, {
+      cwd: repoPath,
+      stdio: "ignore",
+    });
+    branchHeads[branch] = execSync(`git rev-parse ${JSON.stringify(branch)}`, {
+      cwd: repoPath,
+      stdio: "pipe",
+    })
+      .toString()
+      .trim();
+    execSync("git checkout main", { cwd: repoPath, stdio: "ignore" });
+  }
+
   if (withRemote) {
     // Deterministic local remote to avoid relying on external auth/network in e2e.
     const remoteDir = path.join(repoPath, "remote.git");
     await mkdir(remoteDir, { recursive: true });
     execSync(`git init --bare -b main ${remoteDir}`, { cwd: repoPath, stdio: "ignore" });
     execSync(`git remote add origin ${remoteDir}`, { cwd: repoPath, stdio: "ignore" });
-    execSync("git push -u origin main", { cwd: repoPath, stdio: "ignore" });
+    execSync("git push -u origin --all", { cwd: repoPath, stdio: "ignore" });
   }
 
   return {
     path: repoPath,
+    branchHeads,
     cleanup: async () => {
       await rm(repoPath, { recursive: true, force: true });
     },
   };
 };
+
+export async function readWorktreeBranchInfo({ worktreePath }: { worktreePath: string }): Promise<{
+  currentBranch: string;
+  hasAncestor: (ref: string) => boolean;
+}> {
+  const currentBranch = execSync("git branch --show-current", {
+    cwd: worktreePath,
+    stdio: "pipe",
+  })
+    .toString()
+    .trim();
+
+  return {
+    currentBranch,
+    hasAncestor: (ref: string) => {
+      try {
+        execSync(`git merge-base --is-ancestor ${JSON.stringify(ref)} HEAD`, {
+          cwd: worktreePath,
+          stdio: "ignore",
+        });
+        return true;
+      } catch {
+        return false;
+      }
+    },
+  };
+}

packages/app/e2e/new-workspace.spec.ts

@@ -1,3 +1,5 @@
+import { existsSync } from "node:fs";
+import path from "node:path";
 import { buildHostWorkspaceRoute } from "@/utils/host-routes";
 import { expect, test } from "./fixtures";
 import { gotoAppShell } from "./helpers/app";
@@ -8,9 +10,15 @@ import {
   clickNewWorkspaceButton,
   connectNewWorkspaceDaemonClient,
   createWorktreeViaDaemon,
+  expectComposerGithubAttachmentPill,
+  expectStartingRefPickerTriggerPr,
+  openNewWorkspaceComposer,
+  openStartingRefPicker,
   openProjectViaDaemon,
+  selectBranchInPicker,
+  selectGitHubPrInPicker,
 } from "./helpers/new-workspace";
-import { createTempGitRepo } from "./helpers/workspace";
+import { createTempGitRepo, readWorktreeBranchInfo } from "./helpers/workspace";
 import {
   expectSidebarWorkspaceSelected,
   expectWorkspaceHeader,
@@ -254,4 +262,94 @@ test.describe("New workspace flow", () => {
       await tempRepo.cleanup();
     }
   });
+
+  test("selected branch becomes the base of a new workspace worktree", async ({ page }) => {
+    const serverId = process.env.E2E_SERVER_ID;
+    if (!serverId) {
+      throw new Error("E2E_SERVER_ID is not set.");
+    }
+
+    const tempRepo = await createTempGitRepo("new-workspace-ref-", {
+      branches: ["main", "dev"],
+    });
+
+    try {
+      const openedProject = await openProjectViaDaemon(client, tempRepo.path);
+      localWorkspaceIds.add(openedProject.workspaceId);
+
+      await gotoAppShell(page);
+      await waitForSidebarHydration(page);
+
+      await switchWorkspaceViaSidebar({
+        page,
+        serverId,
+        targetWorkspacePath: openedProject.workspaceId,
+      });
+      await expectWorkspaceHeader(page, {
+        title: openedProject.workspaceName,
+        subtitle: openedProject.projectDisplayName,
+      });
+
+      await openNewWorkspaceComposer(page, {
+        projectKey: openedProject.projectKey,
+        projectDisplayName: openedProject.projectDisplayName,
+      });
+      await openStartingRefPicker(page);
+      await selectBranchInPicker(page, "dev");
+
+      const createButton = page
+        .getByTestId("message-input-root")
+        .getByRole("button", { name: "Create" });
+      await expect(createButton).toBeVisible({ timeout: 30_000 });
+      await createButton.click();
+
+      const createdWorkspace = await assertNewWorkspaceSidebarAndHeader(page, {
+        serverId,
+        previousWorkspaceId: openedProject.workspaceId,
+        projectDisplayName: openedProject.projectDisplayName,
+      });
+      createdWorktreeIds.add(createdWorkspace.workspaceId);
+
+      expect(existsSync(createdWorkspace.workspaceId)).toBe(true);
+
+      const branchInfo = await readWorktreeBranchInfo({
+        worktreePath: createdWorkspace.workspaceId,
+      });
+      expect(branchInfo.currentBranch).toBe(path.basename(createdWorkspace.workspaceId));
+      expect(branchInfo.hasAncestor(tempRepo.branchHeads.main)).toBe(true);
+      expect(branchInfo.hasAncestor(tempRepo.branchHeads.dev)).toBe(true);
+    } finally {
+      await tempRepo.cleanup();
+    }
+  });
+
+  test("selected GitHub PR shows PR context in the trigger and composer", async ({ page }) => {
+    const tempRepo = await createTempGitRepo("new-workspace-pr-ref-");
+
+    try {
+      const openedProject = await openProjectViaDaemon(client, tempRepo.path);
+      localWorkspaceIds.add(openedProject.workspaceId);
+
+      await gotoAppShell(page);
+      await waitForSidebarHydration(page);
+      await openNewWorkspaceComposer(page, {
+        projectKey: openedProject.projectKey,
+        projectDisplayName: openedProject.projectDisplayName,
+      });
+      await openStartingRefPicker(page);
+      await selectGitHubPrInPicker(page, 515);
+
+      await expectStartingRefPickerTriggerPr(page, {
+        number: 515,
+        title: "Review selected start ref",
+        headRef: "feature/start-from-pr",
+      });
+      await expectComposerGithubAttachmentPill(page, {
+        number: 515,
+        title: "Review selected start ref",
+      });
+    } finally {
+      await tempRepo.cleanup();
+    }
+  });
 });