fix(installer): bound outputPromise wait after kill to prevent indirect hang

After SIGTERM/SIGKILL escalation, the stdout stream may not close immediately on all platforms. The unconditional await on outputPromise could then hang indefinitely, defeating the bounded process lifetime guarantee. Race outputPromise against a short follow-up timeout to ensure getOpenCodeVersion always returns within a bounded time.

Refs #3766

src/cli/config-manager/opencode-binary.test.ts

@@ -10,7 +10,11 @@ type OpenCodeBinaryModule = typeof import("./opencode-binary")
 type CreateProcOptions = {
   exitCode?: number | null
   exited?: Promise<number>
-  output?: { stdout?: string; stderr?: string }
+  output?: {
+    stdout?: string
+    stdoutStream?: ReadableStream<Uint8Array>
+    stderr?: string
+  }
   kill?: (signal?: NodeJS.Signals) => void
 }
 
@@ -19,7 +23,9 @@ function createProc(options: CreateProcOptions = {}): ReturnType<typeof spawnHel
   return {
     exited: options.exited ?? Promise.resolve(exitCode),
     exitCode,
-    stdout: options.output?.stdout !== undefined ? new Blob([options.output.stdout]).stream() : undefined,
+    stdout:
+      options.output?.stdoutStream ??
+      (options.output?.stdout !== undefined ? new Blob([options.output.stdout]).stream() : undefined),
     stderr: options.output?.stderr !== undefined ? new Blob([options.output.stderr]).stream() : undefined,
     kill: options.kill ?? (() => {}),
   } satisfies ReturnType<typeof spawnHelpers.spawnWithWindowsHide>
@@ -103,6 +109,37 @@ describe("getOpenCodeVersion (installer)", () => {
     })
   })
 
+  describe("#given never-closing stdout after kill #when getOpenCodeVersion #then returns within bounded time", () => {
+    it("bounds outputPromise wait and returns null", async () => {
+      const neverClosingStdout = new ReadableStream<Uint8Array>({
+        start() {
+          // Intentionally never closing to simulate a hung stdout stream.
+        },
+      })
+      spawnSpy.mockReturnValue(
+        createProc({
+          exited: new Promise<number>(() => {}),
+          output: { stdoutStream: neverClosingStdout },
+          kill: () => {},
+        }),
+      )
+
+      const immediateSetTimeout = ((handler: TimerHandler) => {
+        if (typeof handler === "function") {
+          handler()
+        }
+        return 1 as unknown as ReturnType<typeof setTimeout>
+      }) as unknown as typeof globalThis.setTimeout
+      const setTimeoutSpy = spyOn(globalThis, "setTimeout").mockImplementation(immediateSetTimeout)
+
+      const result = await getOpenCodeVersion()
+
+      expect(result).toBe(null)
+
+      setTimeoutSpy.mockRestore()
+    })
+  })
+
   describe("#given quick successful exit #when getOpenCodeVersion #then clears the watchdog timer", () => {
     it("avoids timer leak after success", async () => {
       spawnSpy.mockReturnValue(createProc({ output: { stdout: "1.14.33\n" } }))

src/cli/config-manager/opencode-binary.ts

@@ -6,6 +6,7 @@ import { initConfigContext } from "./config-context"
 const OPENCODE_BINARIES = ["opencode", "opencode-desktop"] as const
 const OPENCODE_VERSION_CHECK_TIMEOUT_MS = 1500
 const OPENCODE_VERSION_KILL_GRACE_MS = 200
+const OPENCODE_OUTPUT_WAIT_TIMEOUT_MS = 200
 
 interface OpenCodeBinaryResult {
   binary: OpenCodeBinaryType
@@ -44,9 +45,9 @@ async function findOpenCodeBinaryWithVersion(): Promise<OpenCodeBinaryResult | n
         new Promise<string>((resolve) => {
           setTimeout(() => {
             resolve("")
-          }, OPENCODE_VERSION_KILL_GRACE_MS)
+          }, OPENCODE_OUTPUT_WAIT_TIMEOUT_MS)
         }),
-      ])
+      ]).catch(() => "")
 
       if (timedExitCode === 0 && proc.exitCode === 0) {
         const version = extractSemverFromOutput(output) ?? output.trim()