fix(opencode): settle RPCs when Rift exits, not when stderr closes

plugins/opencode/src/command.ts

@@ -63,8 +63,8 @@ export function rpc(executable: string, request: object, signal: AbortSignal): P
       }
       chunks.push(chunk)
     })
-    // The background host's stderr may have no reader. Forwarding to it can
-    // pause this stream forever, preventing the child's close event.
+    // The background host's stderr may have no reader, so drain it here rather
+    // than forwarding it there.
     child.stderr.on("data", (chunk: Buffer) => {
       tail = Buffer.concat([tail, chunk]).subarray(-8 * 1024)
     })
@@ -76,8 +76,9 @@ export function rpc(executable: string, request: object, signal: AbortSignal): P
     }
     child.on("error", (error) => finish(() => reject(error)))
     child.stdin.on("error", (error) => finish(() => reject(error)))
-    child.on("close", (code) => {
+    const complete = (code: number | null, killed: NodeJS.Signals | null) => {
       if (settled) return
+      if (killed) return finish(() => reject(new Error(describe(`Rift was terminated by ${killed}`))))
       if (code !== 0) return finish(() => reject(new Error(describe(`Rift exited with status ${code}`))))
       const invalid = () => finish(() => reject(new Error(describe("Rift returned an invalid RPC response"))))
       let response: unknown
@@ -93,7 +94,24 @@ export function rpc(executable: string, request: object, signal: AbortSignal): P
         return finish(() => reject(new RpcError({ ...failure, message: describe(failure.message) })))
       }
       invalid()
+    }
+    // Processes started by hooks inherit stderr and can hold it open long after
+    // Rift exits, so close may never fire. Once Rift has exited and stdout has
+    // ended, give stderr a moment to flush and settle without waiting for close.
+    let exited: [number | null, NodeJS.Signals | null] | undefined
+    let ended = false
+    const drained = () => {
+      if (exited && ended) setTimeout(complete, 100, ...exited).unref()
+    }
+    child.on("exit", (code, killed) => {
+      exited = [code, killed]
+      drained()
+    })
+    child.stdout.on("end", () => {
+      ended = true
+      drained()
     })
+    child.on("close", complete)
     child.stdin.end(JSON.stringify(request))
   })
 }

plugins/opencode/test/command.test.ts

@@ -1,6 +1,6 @@
 import { expect, test } from "bun:test"
 import { spawn } from "node:child_process"
-import { chmod, mkdtemp, rm, writeFile } from "node:fs/promises"
+import { chmod, mkdtemp, readFile, rm, writeFile } from "node:fs/promises"
 import { tmpdir } from "node:os"
 import { join } from "node:path"
 import { fileURLToPath } from "node:url"
@@ -110,3 +110,47 @@ process.stdout.write(${JSON.stringify(JSON.stringify({ status: "error", error: f
     await rm(temp, { recursive: true, force: true })
   }
 })
+
+test("RPCs finish when hook processes keep stderr open", async () => {
+  const temp = await mkdtemp(join(tmpdir(), "opencode-rift-rpc-"))
+  const executable = join(temp, "rift")
+  const pidfile = join(temp, "daemon.pid")
+  await writeFile(
+    executable,
+    `#!/usr/bin/env node
+const { spawn } = require("node:child_process")
+const daemon = spawn("sleep", ["30"], { stdio: ["ignore", "ignore", "inherit"] })
+require("node:fs").writeFileSync(${JSON.stringify(pidfile)}, String(daemon.pid))
+daemon.unref()
+process.stderr.write("compose: port 5432 in use\\n", () => {
+  process.stdout.write(${JSON.stringify(JSON.stringify({ status: "error", error: { code: "hook_failed", message: "postcreate hook failed" } }))})
+})
+`,
+  )
+  await chmod(executable, 0o755)
+  try {
+    await expect(rpc(executable, {}, AbortSignal.timeout(3000))).rejects.toThrow(
+      "postcreate hook failed: compose: port 5432 in use",
+    )
+  } finally {
+    process.kill(Number(await readFile(pidfile, "utf8")))
+    await rm(temp, { recursive: true, force: true })
+  }
+})
+
+test("signal deaths name the signal", async () => {
+  const temp = await mkdtemp(join(tmpdir(), "opencode-rift-rpc-"))
+  const executable = join(temp, "rift")
+  await writeFile(
+    executable,
+    '#!/usr/bin/env node\nprocess.stderr.write("fatal runtime error\\n", () => process.kill(process.pid, "SIGKILL"))\n',
+  )
+  await chmod(executable, 0o755)
+  try {
+    await expect(rpc(executable, {}, AbortSignal.timeout(3000))).rejects.toThrow(
+      "Rift was terminated by SIGKILL: fatal runtime error",
+    )
+  } finally {
+    await rm(temp, { recursive: true, force: true })
+  }
+})