fix: finalize exec fish fallback (#1297) (thanks @ysqander)

src/agents/shell-utils.test.ts

@@ -0,0 +1,82 @@
+import fs from "node:fs";
+import os from "node:os";
+import path from "node:path";
+
+import { afterEach, beforeEach, describe, expect, it } from "vitest";
+import { getShellConfig } from "./shell-utils.js";
+
+const isWin = process.platform === "win32";
+
+describe("getShellConfig", () => {
+  const originalShell = process.env.SHELL;
+  const originalPath = process.env.PATH;
+  const tempDirs: string[] = [];
+
+  const createTempBin = (files: string[]) => {
+    const dir = fs.mkdtempSync(path.join(os.tmpdir(), "clawdbot-shell-"));
+    tempDirs.push(dir);
+    for (const name of files) {
+      const filePath = path.join(dir, name);
+      fs.writeFileSync(filePath, "");
+      fs.chmodSync(filePath, 0o755);
+    }
+    return dir;
+  };
+
+  beforeEach(() => {
+    if (!isWin) {
+      process.env.SHELL = "/usr/bin/fish";
+    }
+  });
+
+  afterEach(() => {
+    if (originalShell == null) {
+      delete process.env.SHELL;
+    } else {
+      process.env.SHELL = originalShell;
+    }
+    if (originalPath == null) {
+      delete process.env.PATH;
+    } else {
+      process.env.PATH = originalPath;
+    }
+    for (const dir of tempDirs.splice(0)) {
+      fs.rmSync(dir, { recursive: true, force: true });
+    }
+  });
+
+  if (isWin) {
+    it("uses PowerShell on Windows", () => {
+      const { shell } = getShellConfig();
+      expect(shell.toLowerCase()).toContain("powershell");
+    });
+    return;
+  }
+
+  it("prefers bash when fish is default and bash is on PATH", () => {
+    const binDir = createTempBin(["bash"]);
+    process.env.PATH = binDir;
+    const { shell } = getShellConfig();
+    expect(shell).toBe(path.join(binDir, "bash"));
+  });
+
+  it("falls back to sh when fish is default and bash is missing", () => {
+    const binDir = createTempBin(["sh"]);
+    process.env.PATH = binDir;
+    const { shell } = getShellConfig();
+    expect(shell).toBe(path.join(binDir, "sh"));
+  });
+
+  it("falls back to env shell when fish is default and no sh is available", () => {
+    process.env.PATH = "";
+    const { shell } = getShellConfig();
+    expect(shell).toBe("/usr/bin/fish");
+  });
+
+  it("uses sh when SHELL is unset", () => {
+    delete process.env.SHELL;
+    process.env.PATH = "";
+    const { shell } = getShellConfig();
+    expect(shell).toBe("sh");
+  });
+});

src/agents/shell-utils.ts

@@ -1,7 +1,6 @@
 import fs from "node:fs";
 import path from "node:path";
 import { spawn } from "node:child_process";
-import path from "node:path";
 
 function resolvePowerShellPath(): string {
   const systemRoot = process.env.SystemRoot || process.env.WINDIR;
@@ -35,12 +34,31 @@ export function getShellConfig(): { shell: string; args: string[] } {
   const shellName = envShell ? path.basename(envShell) : "";
   // Fish rejects common bashisms used by tools, so prefer bash when detected.
   if (shellName === "fish") {
-    return { shell: "/bin/bash", args: ["-c"] };
+    const bash = resolveShellFromPath("bash");
+    if (bash) return { shell: bash, args: ["-c"] };
+    const sh = resolveShellFromPath("sh");
+    if (sh) return { shell: sh, args: ["-c"] };
   }
-  const shell = envShell || "sh";
+  const shell = envShell && envShell.length > 0 ? envShell : "sh";
   return { shell, args: ["-c"] };
 }
 
+function resolveShellFromPath(name: string): string | undefined {
+  const envPath = process.env.PATH ?? "";
+  if (!envPath) return undefined;
+  const entries = envPath.split(path.delimiter).filter(Boolean);
+  for (const entry of entries) {
+    const candidate = path.join(entry, name);
+    try {
+      fs.accessSync(candidate, fs.constants.X_OK);
+      return candidate;
+    } catch {
+      // ignore missing or non-executable entries
+    }
+  }
+  return undefined;
+}
+
 export function sanitizeBinaryOutput(text: string): string {
   const scrubbed = text.replace(/[\p{Format}\p{Surrogate}]/gu, "");
   if (!scrubbed) return scrubbed;

src/process/command-queue.ts

@@ -111,7 +111,7 @@ export function enqueueCommand<T>(
   return enqueueCommandInLane(CommandLane.Main, task, opts);
 }
 
-export function getQueueSize(lane = CommandLane.Main) {
+export function getQueueSize(lane: string = CommandLane.Main) {
   const state = lanes.get(lane);
   if (!state) return 0;
   return state.queue.length + state.active;
@@ -125,7 +125,7 @@ export function getTotalQueueSize() {
   return total;
 }
 
-export function clearCommandLane(lane = CommandLane.Main) {
+export function clearCommandLane(lane: string = CommandLane.Main) {
   const cleaned = lane.trim() || CommandLane.Main;
   const state = lanes.get(cleaned);
   if (!state) return 0;