fix(session-notification): use node:child_process to avoid Bun shell GC crash (#543)

Replace Bun shell template literals (ctx.$) with node:child_process.spawn
to work around Bun's ShellInterpreter garbage collection bug on Windows.

This bug causes segmentation faults in deinitFromFinalizer during heap
sweeping when shell operations are used repeatedly over time.

Bug references:
- oven-sh/bun#23177 (closed incomplete)
- oven-sh/bun#24368 (still open)
- Pending fix: oven-sh/bun#24093

The fix applies to all platforms for consistency and safety.

src/hooks/session-notification.test.ts

@@ -1,4 +1,6 @@
-import { describe, expect, test, beforeEach, afterEach, spyOn } from "bun:test"
+import { describe, expect, test, beforeEach, afterEach, spyOn, mock } from "bun:test"
+import { EventEmitter } from "node:events"
+import * as childProcess from "node:child_process"
 
 import { createSessionNotification } from "./session-notification"
 import { setMainSession, subagentSessions } from "../features/claude-code-session-state"
@@ -6,20 +8,11 @@ import * as utils from "./session-notification-utils"
 
 describe("session-notification", () => {
   let notificationCalls: string[]
+  let spawnMock: ReturnType<typeof spyOn>
 
   function createMockPluginInput() {
     return {
-      $: async (cmd: TemplateStringsArray | string, ...values: any[]) => {
-        // #given - track notification commands (osascript, notify-send, powershell)
-        const cmdStr = typeof cmd === "string" 
-          ? cmd 
-          : cmd.reduce((acc, part, i) => acc + part + (values[i] ?? ""), "")
-        
-        if (cmdStr.includes("osascript") || cmdStr.includes("notify-send") || cmdStr.includes("powershell")) {
-          notificationCalls.push(cmdStr)
-        }
-        return { stdout: "", stderr: "", exitCode: 0 }
-      },
+      $: async () => ({ stdout: "", stderr: "", exitCode: 0 }),
       client: {
         session: {
           todo: async () => ({ data: [] }),
@@ -32,6 +25,18 @@ describe("session-notification", () => {
   beforeEach(() => {
     notificationCalls = []
     
+    // Mock spawn to track notification commands
+    // Uses node:child_process.spawn instead of Bun shell to avoid GC crash
+    spawnMock = spyOn(childProcess, "spawn").mockImplementation((cmd: string, args?: string[]) => {
+      // Track notification commands (osascript, notify-send, powershell)
+      if (cmd.includes("osascript") || cmd.includes("notify-send") || cmd.includes("powershell")) {
+        notificationCalls.push(`${cmd} ${(args ?? []).join(" ")}`)
+      }
+      const emitter = new EventEmitter()
+      setTimeout(() => emitter.emit("close", 0), 0)
+      return emitter as any
+    })
+    
     spyOn(utils, "getOsascriptPath").mockResolvedValue("/usr/bin/osascript")
     spyOn(utils, "getNotifySendPath").mockResolvedValue("/usr/bin/notify-send")
     spyOn(utils, "getPowershellPath").mockResolvedValue("powershell")

src/hooks/session-notification.ts

@@ -1,5 +1,6 @@
 import type { PluginInput } from "@opencode-ai/plugin"
 import { platform } from "os"
+import { spawn } from "node:child_process"
 import { subagentSessions, getMainSessionID } from "../features/claude-code-session-state"
 import {
   getOsascriptPath,
@@ -11,6 +12,21 @@ import {
   startBackgroundCheck,
 } from "./session-notification-utils"
 
+/**
+ * Execute a command using node:child_process instead of Bun shell.
+ * This avoids Bun's ShellInterpreter GC bug on Windows (oven-sh/bun#23177, #24368).
+ */
+function execCommand(command: string, args: string[]): Promise<void> {
+  return new Promise((resolve) => {
+    const proc = spawn(command, args, {
+      stdio: "ignore",
+      detached: false,
+    })
+    proc.on("close", () => resolve())
+    proc.on("error", () => resolve())
+  })
+}
+
 interface Todo {
   content: string
   status: string
@@ -65,14 +81,17 @@ async function sendNotification(
 
       const esTitle = title.replace(/\\/g, "\\\\").replace(/"/g, '\\"')
       const esMessage = message.replace(/\\/g, "\\\\").replace(/"/g, '\\"')
-      await ctx.$`${osascriptPath} -e ${"display notification \"" + esMessage + "\" with title \"" + esTitle + "\""}`.catch(() => {})
+      const script = `display notification "${esMessage}" with title "${esTitle}"`
+      // Use node:child_process instead of Bun shell to avoid potential GC issues
+      await execCommand(osascriptPath, ["-e", script]).catch(() => {})
       break
     }
     case "linux": {
       const notifySendPath = await getNotifySendPath()
       if (!notifySendPath) return
 
-      await ctx.$`${notifySendPath} ${title} ${message} 2>/dev/null`.catch(() => {})
+      // Use node:child_process instead of Bun shell to avoid potential GC issues
+      await execCommand(notifySendPath, [title, message]).catch(() => {})
       break
     }
     case "win32": {
@@ -93,7 +112,8 @@ $Toast = [Windows.UI.Notifications.ToastNotification]::new($SerializedXml)
 $Notifier = [Windows.UI.Notifications.ToastNotificationManager]::CreateToastNotifier('OpenCode')
 $Notifier.Show($Toast)
 `.trim().replace(/\n/g, "; ")
-      await ctx.$`${powershellPath} -Command ${toastScript}`.catch(() => {})
+      // Use node:child_process instead of Bun shell to avoid GC crash (oven-sh/bun#23177)
+      await execCommand(powershellPath, ["-Command", toastScript]).catch(() => {})
       break
     }
   }
@@ -104,17 +124,19 @@ async function playSound(ctx: PluginInput, p: Platform, soundPath: string): Prom
     case "darwin": {
       const afplayPath = await getAfplayPath()
       if (!afplayPath) return
-      ctx.$`${afplayPath} ${soundPath}`.catch(() => {})
+      // Use node:child_process instead of Bun shell to avoid potential GC issues
+      execCommand(afplayPath, [soundPath]).catch(() => {})
       break
     }
     case "linux": {
       const paplayPath = await getPaplayPath()
       if (paplayPath) {
-        ctx.$`${paplayPath} ${soundPath} 2>/dev/null`.catch(() => {})
+        // Use node:child_process instead of Bun shell to avoid potential GC issues
+        execCommand(paplayPath, [soundPath]).catch(() => {})
       } else {
         const aplayPath = await getAplayPath()
         if (aplayPath) {
-          ctx.$`${aplayPath} ${soundPath} 2>/dev/null`.catch(() => {})
+          execCommand(aplayPath, [soundPath]).catch(() => {})
         }
       }
       break
@@ -122,7 +144,9 @@ async function playSound(ctx: PluginInput, p: Platform, soundPath: string): Prom
     case "win32": {
       const powershellPath = await getPowershellPath()
       if (!powershellPath) return
-      ctx.$`${powershellPath} -Command ${"(New-Object Media.SoundPlayer '" + soundPath + "').PlaySync()"}`.catch(() => {})
+      // Use node:child_process instead of Bun shell to avoid GC crash (oven-sh/bun#23177)
+      const soundScript = `(New-Object Media.SoundPlayer '${soundPath.replace(/'/g, "''")}').PlaySync()`
+      execCommand(powershellPath, ["-Command", soundScript]).catch(() => {})
       break
     }
   }