Add shell executable support

modules.go

@@ -318,7 +318,7 @@ func (e *Executor) moduleShell(ctx context.Context, client sshExecutorClient, ar
 		cmd = prefixCommandStdin(cmd, stdin, getBoolArg(args, "stdin_add_newline", true))
 	}
 
-	stdout, stderr, rc, err := client.RunScript(ctx, cmd)
+	stdout, stderr, rc, err := runShellScriptCommand(ctx, client, cmd, getStringArg(args, "executable", ""))
 	if err != nil {
 		return &TaskResult{Failed: true, Msg: err.Error(), Stdout: stdout, Stderr: stderr, RC: rc}, nil
 	}
@@ -508,7 +508,7 @@ func (e *Executor) moduleScript(ctx context.Context, client sshExecutorClient, a
 		data = sprintf("cd %q && %s", chdir, data)
 	}
 
-	stdout, stderr, rc, err := client.RunScript(ctx, data)
+	stdout, stderr, rc, err := runShellScriptCommand(ctx, client, data, getStringArg(args, "executable", ""))
 	if err != nil {
 		return &TaskResult{Failed: true, Msg: err.Error()}, nil
 	}
@@ -522,6 +522,21 @@ func (e *Executor) moduleScript(ctx context.Context, client sshExecutorClient, a
 	}, nil
 }
 
+// runShellScriptCommand executes a shell script using either the default
+// heredoc path or a caller-specified executable.
+//
+// Example:
+//
+//	stdout, stderr, rc, err := runShellScriptCommand(ctx, client, "echo hi", "/bin/dash")
+func runShellScriptCommand(ctx context.Context, client sshExecutorClient, script, executable string) (stdout, stderr string, exitCode int, err error) {
+	if executable == "" {
+		return client.RunScript(ctx, script)
+	}
+
+	cmd := sprintf("%s -c %s", shellSingleQuote(executable), shellSingleQuote(script))
+	return client.Run(ctx, cmd)
+}
+
 // --- File Modules ---
 
 func (e *Executor) moduleCopy(ctx context.Context, client sshExecutorClient, args map[string]any, host string, task *Task) (*TaskResult, error) {

modules_cmd_test.go

@@ -415,6 +415,26 @@ func TestModulesCmd_ModuleShell_Good_WithChdir(t *testing.T) {
 	assert.Contains(t, last.Cmd, "npm install")
 }
 
+func TestModulesCmd_ModuleShell_Good_ExecutableUsesRun(t *testing.T) {
+	e, mock := newTestExecutorWithMock("host1")
+	mock.expectCommand(`/bin/dash.*echo test`, "test\n", "", 0)
+
+	result, err := e.moduleShell(context.Background(), mock, map[string]any{
+		"_raw_params": "echo test",
+		"executable":  "/bin/dash",
+	})
+
+	require.NoError(t, err)
+	assert.True(t, result.Changed)
+
+	last := mock.lastCommand()
+	require.NotNil(t, last)
+	assert.Equal(t, "Run", last.Method)
+	assert.Contains(t, last.Cmd, "/bin/dash")
+	assert.Contains(t, last.Cmd, "-c")
+	assert.Contains(t, last.Cmd, "echo test")
+}
+
 func TestModulesCmd_ModuleShell_Bad_NoCommand(t *testing.T) {
 	e, _ := newTestExecutorWithMock("host1")
 	mock := NewMockSSHClient()
@@ -642,6 +662,31 @@ func TestModulesCmd_ModuleScript_Good_ChdirPrefixesScript(t *testing.T) {
 	assert.Equal(t, `cd "/opt/app" && pwd`, last.Cmd)
 }
 
+func TestModulesCmd_ModuleScript_Good_ExecutableUsesRun(t *testing.T) {
+	tmpDir := t.TempDir()
+	scriptPath := joinPath(tmpDir, "dash.sh")
+	require.NoError(t, writeTestFile(scriptPath, []byte("echo script works"), 0755))
+
+	e, mock := newTestExecutorWithMock("host1")
+	mock.expectCommand(`/bin/dash.*echo script works`, "script works\n", "", 0)
+
+	result, err := e.moduleScript(context.Background(), mock, map[string]any{
+		"_raw_params": scriptPath,
+		"executable":  "/bin/dash",
+	})
+
+	require.NoError(t, err)
+	require.NotNil(t, result)
+	assert.True(t, result.Changed)
+
+	last := mock.lastCommand()
+	require.NotNil(t, last)
+	assert.Equal(t, "Run", last.Method)
+	assert.Contains(t, last.Cmd, "/bin/dash")
+	assert.Contains(t, last.Cmd, "-c")
+	assert.Contains(t, last.Cmd, "echo script works")
+}
+
 func TestModulesCmd_ModuleScript_Bad_NoScript(t *testing.T) {
 	e, _ := newTestExecutorWithMock("host1")
 	mock := NewMockSSHClient()