src/pkg/cosboot/grubconfig_test.go

// Copyright 2026 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package cosboot

import (
	"os"
	"path/filepath"
	"testing"

	"cos.googlesource.com/cos/tools.git/src/pkg/utils"
)

func TestNextGRUBCmdLine(t *testing.T) {
	tests := []struct {
		name  string
		input string
		want  string
	}{
		{
			name:  "BootA",
			input: "testdata/grubcfgA.img",
			want:  `/syslinux/vmlinuz.A init=/usr/lib/systemd/systemd rootwait ro noresume loglevel=7 console=tty1 console=ttyS0,115200 security=apparmor virtio_net.napi_tx=1 nmi_watchdog=0 csm.disabled=1 loadpin.exclude=kernel-module,firmware modules-load=loadpin_trigger firmware_class.path=/var/lib/nvidia/firmware module.sig_enforce=1  dm_verity.error_behavior=3 dm_verity.max_bios=-1 dm_verity.dev_wait=1       i915.modeset=1 cros_efi root=/dev/dm-0 dm-mod.create="vroot,,,ro,0 4077568 verity 0 PARTUUID=D4A2048A-D85B-C146-A5E0-08A1251A55C2 PARTUUID=D4A2048A-D85B-C146-A5E0-08A1251A55C2 4096 4096 509696 509696 sha256 cd98fb63a9a93194d8465937c46fce496143b4441be776bf504d9f09093e308d ad6ac492b67f319a8ebf86f034af467d207bffb20483a039b80e6c2e4572e0b4"`,
		},
		{
			name:  "BootB",
			input: "testdata/grubcfgB.img",
			want:  `/syslinux/vmlinuz.B init=/usr/lib/systemd/systemd rootwait ro noresume loglevel=7 console=tty1 console=ttyS0,115200 security=apparmor virtio_net.napi_tx=1 nmi_watchdog=0 csm.disabled=1 loadpin.exclude=kernel-module,firmware modules-load=loadpin_trigger firmware_class.path=/var/lib/nvidia/firmware module.sig_enforce=1  dm_verity.error_behavior=3 dm_verity.max_bios=-1 dm_verity.dev_wait=1       i915.modeset=1 cros_efi root=/dev/dm-0 dm-mod.create="vroot,,,ro,0 4077568 verity 0 PARTUUID=336A62C8-AF4C-F54C-AEB8-322675266630 PARTUUID=336A62C8-AF4C-F54C-AEB8-322675266630 4096 4096 509696 509696 sha256 cd98fb63a9a93194d8465937c46fce496143b4441be776bf504d9f09093e308d ad6ac492b67f319a8ebf86f034af467d207bffb20483a039b80e6c2e4572e0b4"`,
		},
	}
	for _, test := range tests {
		test := test
		t.Run(test.name, func(t *testing.T) {
			got, err := NextGRUBCmdLine(test.input)
			if err != nil {
				t.Fatalf("NextGRUBCmdLine(%q) = %v; want nil", test.input, err)
			}
			if got != test.want {
				t.Errorf("NextGRUBCmdLine(%q) = %q; want %q", test.input, got, test.want)
			}
		})
	}

}

func TestEditGRUBConfig(t *testing.T) {
	tests := []struct {
		name   string
		input  string
		sedCmd string
		want   string
	}{
		{
			name:   "BootA",
			input:  "testdata/grubcfgA.img",
			sedCmd: "s|cros_efi|cros_efi mitigations=off|g",
			want:   `/syslinux/vmlinuz.A init=/usr/lib/systemd/systemd rootwait ro noresume loglevel=7 console=tty1 console=ttyS0,115200 security=apparmor virtio_net.napi_tx=1 nmi_watchdog=0 csm.disabled=1 loadpin.exclude=kernel-module,firmware modules-load=loadpin_trigger firmware_class.path=/var/lib/nvidia/firmware module.sig_enforce=1  dm_verity.error_behavior=3 dm_verity.max_bios=-1 dm_verity.dev_wait=1       i915.modeset=1 cros_efi mitigations=off root=/dev/dm-0 dm-mod.create="vroot,,,ro,0 4077568 verity 0 PARTUUID=D4A2048A-D85B-C146-A5E0-08A1251A55C2 PARTUUID=D4A2048A-D85B-C146-A5E0-08A1251A55C2 4096 4096 509696 509696 sha256 cd98fb63a9a93194d8465937c46fce496143b4441be776bf504d9f09093e308d ad6ac492b67f319a8ebf86f034af467d207bffb20483a039b80e6c2e4572e0b4"`,
		},
		{
			name:   "BootB",
			input:  "testdata/grubcfgB.img",
			sedCmd: "s|cros_efi|cros_efi mitigations=off|g",
			want:   `/syslinux/vmlinuz.B init=/usr/lib/systemd/systemd rootwait ro noresume loglevel=7 console=tty1 console=ttyS0,115200 security=apparmor virtio_net.napi_tx=1 nmi_watchdog=0 csm.disabled=1 loadpin.exclude=kernel-module,firmware modules-load=loadpin_trigger firmware_class.path=/var/lib/nvidia/firmware module.sig_enforce=1  dm_verity.error_behavior=3 dm_verity.max_bios=-1 dm_verity.dev_wait=1       i915.modeset=1 cros_efi mitigations=off root=/dev/dm-0 dm-mod.create="vroot,,,ro,0 4077568 verity 0 PARTUUID=336A62C8-AF4C-F54C-AEB8-322675266630 PARTUUID=336A62C8-AF4C-F54C-AEB8-322675266630 4096 4096 509696 509696 sha256 cd98fb63a9a93194d8465937c46fce496143b4441be776bf504d9f09093e308d ad6ac492b67f319a8ebf86f034af467d207bffb20483a039b80e6c2e4572e0b4"`,
		},
	}
	for _, test := range tests {
		test := test
		t.Run(test.name, func(t *testing.T) {
			tmpDir, err := os.MkdirTemp("", "cosboot-test-")
			if err != nil {
				t.Fatal(err)
			}
			defer os.RemoveAll(tmpDir)
			copiedInput := filepath.Join(tmpDir, "input")
			if err := utils.CopyFile(test.input, copiedInput); err != nil {
				t.Fatal(err)
			}
			if err := EditGRUBConfig(copiedInput, test.sedCmd); err != nil {
				t.Fatalf("EditGRUBConfig(%q, %q) = %v; want nil", test.input, test.sedCmd, err)
			}
			got, err := NextGRUBCmdLine(copiedInput)
			if err != nil {
				t.Fatalf("NextGRUBCmdLine(%q) = %v; want nil", test.input, err)
			}
			if got != test.want {
				t.Errorf("NextGRUBCmdLine(%q) = %q; want %q", test.input, got, test.want)
			}
		})
	}

}