wip: poc pr command

2 files changed, 87 insertions, 0 deletions

diff --git a/packages/opencode/src/cli/cmd/pr.ts b/packages/opencode/src/cli/cmd/pr.ts
new file mode 100644
index 000000000..fb6171a71
--- /dev/null
+++ b/packages/opencode/src/cli/cmd/pr.ts
@@ -0,0 +1,85 @@
+import { UI } from "../ui"
+import { cmd } from "./cmd"
+import { Instance } from "@/project/instance"
+import { $ } from "bun"
+
+export const PrCommand = cmd({
+  command: "pr <number>",
+  describe: "fetch and checkout a GitHub PR branch, then run opencode",
+  builder: (yargs) =>
+    yargs.positional("number", {
+      type: "number",
+      describe: "PR number to checkout",
+      demandOption: true,
+    }),
+  async handler(args) {
+    await Instance.provide({
+      directory: process.cwd(),
+      async fn() {
+        const project = Instance.project
+        if (project.vcs !== "git") {
+          UI.error("Could not find git repository. Please run this command from a git repository.")
+          process.exit(1)
+        }
+
+        const prNumber = args.number
+        const localBranchName = `pr/${prNumber}`
+        UI.println(`Fetching and checking out PR #${prNumber}...`)
+
+        // Use gh pr checkout with custom branch name
+        const result = await $`gh pr checkout ${prNumber} --branch ${localBranchName} --force`.nothrow()
+
+        if (result.exitCode !== 0) {
+          UI.error(`Failed to checkout PR #${prNumber}. Make sure you have gh CLI installed and authenticated.`)
+          process.exit(1)
+        }
+
+        // For fork PRs, add the fork as a remote to enable pushing
+        const prInfoResult =
+          await $`gh pr view ${prNumber} --json headRepository,headRepositoryOwner,isCrossRepository,headRefName`.nothrow()
+        if (prInfoResult.exitCode === 0) {
+          const prInfoText = prInfoResult.text()
+          if (prInfoText.trim()) {
+            const prInfo = JSON.parse(prInfoText)
+            if (prInfo && prInfo.isCrossRepository && prInfo.headRepository && prInfo.headRepositoryOwner) {
+              const forkOwner = prInfo.headRepositoryOwner.login
+              const forkName = prInfo.headRepository.name
+              const remoteName = forkOwner
+
+              // Check if remote already exists
+              const remotes = (await $`git remote`.nothrow().text()).trim()
+              if (!remotes.split("\n").includes(remoteName)) {
+                await $`git remote add ${remoteName} https://github.com/${forkOwner}/${forkName}.git`.nothrow()
+                UI.println(`Added fork remote: ${remoteName}`)
+              }
+
+              // Set upstream to the fork so pushes go there
+              const headRefName = prInfo.headRefName
+              await $`git branch --set-upstream-to=${remoteName}/${headRefName} ${localBranchName}`.nothrow()
+            }
+          }
+        }
+
+        UI.println(`Successfully checked out PR #${prNumber} as branch '${localBranchName}'`)
+        UI.println()
+        UI.println("Starting opencode...")
+        UI.println()
+
+        // Launch opencode TUI
+        const { spawn } = await import("child_process")
+        const opencodeProcess = spawn("opencode", [], {
+          stdio: "inherit",
+          cwd: process.cwd(),
+        })
+
+        await new Promise<void>((resolve, reject) => {
+          opencodeProcess.on("exit", (code) => {
+            if (code === 0) resolve()
+            else reject(new Error(`opencode exited with code ${code}`))
+          })
+          opencodeProcess.on("error", reject)
+        })
+      },
+    })
+  },
+})
diff --git a/packages/opencode/src/index.ts b/packages/opencode/src/index.ts
index 015806997..acd7ee1c0 100644
--- a/packages/opencode/src/index.ts
+++ b/packages/opencode/src/index.ts
@@ -24,6 +24,7 @@ import { TuiSpawnCommand } from "./cli/cmd/tui/spawn"
 import { AcpCommand } from "./cli/cmd/acp"
 import { EOL } from "os"
 import { WebCommand } from "./cli/cmd/web"
+import { PrCommand } from "./cli/cmd/pr"
 
 process.on("unhandledRejection", (e) => {
   Log.Default.error("rejection", {
@@ -90,6 +91,7 @@ const cli = yargs(hideBin(process.argv))
   .command(ExportCommand)
   .command(ImportCommand)
   .command(GithubCommand)
+  .command(PrCommand)
   .fail((msg) => {
     if (
       msg.startsWith("Unknown argument") ||