fix(opencode): prevent literal nul file creation on posix

packages/opencode/src/session/prompt.ts

@@ -45,6 +45,7 @@ import { LLM } from "./llm"
 import { iife } from "@/util/iife"
 import { Shell } from "@/shell/shell"
 import { Truncate } from "@/tool/truncation"
+import { normalizeNul } from "@/util/redirection"
 
 // @ts-ignore
 globalThis.AI_SDK_LOG_WARNINGS = false
@@ -1471,6 +1472,7 @@ NOTE: At any point in time through this workflow you should feel free to ask the
   })
   export type ShellInput = z.infer<typeof ShellInput>
   export async function shell(input: ShellInput) {
+    const command = normalizeNul(input.command, process.platform)
     const abort = start(input.sessionID)
     if (!abort) {
       throw new Session.BusyError(input.sessionID)
@@ -1557,7 +1559,7 @@ NOTE: At any point in time through this workflow you should feel free to ask the
           start: Date.now(),
         },
         input: {
-          command: input.command,
+          command,
         },
       },
     }
@@ -1569,10 +1571,10 @@ NOTE: At any point in time through this workflow you should feel free to ask the
 
     const invocations: Record<string, { args: string[] }> = {
       nu: {
-        args: ["-c", input.command],
+        args: ["-c", command],
       },
       fish: {
-        args: ["-c", input.command],
+        args: ["-c", command],
       },
       zsh: {
         args: [
@@ -1581,7 +1583,7 @@ NOTE: At any point in time through this workflow you should feel free to ask the
           `
             [[ -f ~/.zshenv ]] && source ~/.zshenv >/dev/null 2>&1 || true
             [[ -f "\${ZDOTDIR:-$HOME}/.zshrc" ]] && source "\${ZDOTDIR:-$HOME}/.zshrc" >/dev/null 2>&1 || true
-            eval ${JSON.stringify(input.command)}
+            eval ${JSON.stringify(command)}
           `,
         ],
       },
@@ -1592,25 +1594,25 @@ NOTE: At any point in time through this workflow you should feel free to ask the
           `
             shopt -s expand_aliases
             [[ -f ~/.bashrc ]] && source ~/.bashrc >/dev/null 2>&1 || true
-            eval ${JSON.stringify(input.command)}
+            eval ${JSON.stringify(command)}
           `,
         ],
       },
       // Windows cmd
       cmd: {
-        args: ["/c", input.command],
+        args: ["/c", command],
       },
       // Windows PowerShell
       powershell: {
-        args: ["-NoProfile", "-Command", input.command],
+        args: ["-NoProfile", "-Command", command],
       },
       pwsh: {
-        args: ["-NoProfile", "-Command", input.command],
+        args: ["-NoProfile", "-Command", command],
       },
       // Fallback: any shell that doesn't match those above
       //  - No -l, for max compatibility
       "": {
-        args: ["-c", `${input.command}`],
+        args: ["-c", `${command}`],
       },
     }
 
@@ -1626,13 +1628,14 @@ NOTE: At any point in time through this workflow you should feel free to ask the
     const proc = spawn(shell, args, {
       cwd,
       detached: process.platform !== "win32",
-      stdio: ["ignore", "pipe", "pipe"],
+      stdio: ["pipe", "pipe", "pipe"],
       env: {
         ...process.env,
         ...shellEnv.env,
         TERM: "dumb",
       },
     })
+    proc.stdin?.end()
 
     let output = ""
 

packages/opencode/src/tool/bash.ts

@@ -17,6 +17,7 @@ import { Shell } from "@/shell/shell"
 import { BashArity } from "@/permission/arity"
 import { Truncate } from "./truncation"
 import { Plugin } from "@/plugin"
+import { normalizeNul } from "@/util/redirection"
 
 const MAX_METADATA_LENGTH = 30_000
 const DEFAULT_TIMEOUT = Flag.OPENCODE_EXPERIMENTAL_BASH_DEFAULT_TIMEOUT_MS || 2 * 60 * 1000
@@ -76,12 +77,13 @@ export const BashTool = Tool.define("bash", async () => {
         ),
     }),
     async execute(params, ctx) {
+      const command = normalizeNul(params.command, process.platform)
       const cwd = params.workdir || Instance.directory
       if (params.timeout !== undefined && params.timeout < 0) {
         throw new Error(`Invalid timeout value: ${params.timeout}. Timeout must be a positive number.`)
       }
       const timeout = params.timeout ?? DEFAULT_TIMEOUT
-      const tree = await parser().then((p) => p.parse(params.command))
+      const tree = await parser().then((p) => p.parse(command))
       if (!tree) {
         throw new Error("Failed to parse command")
       }
@@ -169,16 +171,17 @@ export const BashTool = Tool.define("bash", async () => {
         { cwd, sessionID: ctx.sessionID, callID: ctx.callID },
         { env: {} },
       )
-      const proc = spawn(params.command, {
+      const proc = spawn(command, {
         shell,
         cwd,
         env: {
           ...process.env,
           ...shellEnv.env,
         },
-        stdio: ["ignore", "pipe", "pipe"],
+        stdio: ["pipe", "pipe", "pipe"],
         detached: process.platform !== "win32",
       })
+      proc.stdin?.end()
 
       let output = ""
 

packages/opencode/src/util/redirection.ts

@@ -0,0 +1,9 @@
+const OPS = "(?:\\d+>>?|>>|>|&>|>&)"
+
+export function normalizeNul(command: string, platform: string) {
+  if (platform === "win32") return command
+
+  return command
+    .replace(new RegExp(`(^|[\\s;|&(])(${OPS}\\s*)["']nul["'](?=($|[\\s;|&)]))`, "gi"), "$1$2/dev/null")
+    .replace(new RegExp(`(^|[\\s;|&(])(${OPS}\\s*)nul(?=($|[\\s;|&)]))`, "gi"), "$1$2/dev/null")
+}

packages/opencode/test/util/redirection.test.ts

@@ -0,0 +1,16 @@
+import { describe, expect, test } from "bun:test"
+import { normalizeNul } from "../../src/util/redirection"
+
+describe("util.redirection", () => {
+  test("rewrites nul redirect targets on non-windows", () => {
+    expect(normalizeNul("dir /s *.dll >nul 2>&1", "linux")).toBe("dir /s *.dll >/dev/null 2>&1")
+    expect(normalizeNul("echo hi 2> NUL", "linux")).toBe("echo hi 2> /dev/null")
+    expect(normalizeNul("echo hi >> 'nul'", "linux")).toBe("echo hi >> /dev/null")
+    expect(normalizeNul("dir /s *.dll >nul 2>&1", "win32")).toBe("dir /s *.dll >nul 2>&1")
+  })
+
+  test("does not touch ordinary file paths", () => {
+    expect(normalizeNul("cat ./nul.txt", "linux")).toBe("cat ./nul.txt")
+    expect(normalizeNul("echo hi > ./nul", "linux")).toBe("echo hi > ./nul")
+  })
+})