Add yq subcommands to limactl and lima-guestagent

Adding it to `lima-guestagent` allows us to use `yq` in provisioning
scripts without having to install it from a package repository or
downloading it from GitHub.

Adding it to `limactl` makes it available to integration tests without
having to install it. It is essentially free because we already use
`yqlib` inside `limactl` anyways, , so the executable size doesn't
really change.

The size of the (compressed) guestagent for aarch64 increases from
12MB to 14MB, which seems acceptable.

These are "hidden" commands that don't show up in --help output.

Signed-off-by: Jan Dubois <jan.dubois@suse.com>

Author: jandubois

cmd/lima-guestagent/main_linux.go

@@ -9,11 +9,13 @@ import (
 	"github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
 
+	"github.com/lima-vm/lima/v2/cmd/yq"
 	"github.com/lima-vm/lima/v2/pkg/debugutil"
 	"github.com/lima-vm/lima/v2/pkg/version"
 )
 
 func main() {
+	yq.MaybeRunYQ()
 	if err := newApp().Execute(); err != nil {
 		logrus.Fatal(err)
 	}

cmd/limactl/main.go

@@ -17,6 +17,7 @@ import (
 	"github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
 
+	"github.com/lima-vm/lima/v2/cmd/yq"
 	"github.com/lima-vm/lima/v2/pkg/debugutil"
 	"github.com/lima-vm/lima/v2/pkg/driver/external/server"
 	"github.com/lima-vm/lima/v2/pkg/fsutil"
@@ -32,6 +33,7 @@ const (
 )
 
 func main() {
+	yq.MaybeRunYQ()
 	if runtime.GOOS == "windows" {
 		extras, hasExtra := os.LookupEnv("_LIMA_WINDOWS_EXTRA_PATH")
 		if hasExtra && strings.TrimSpace(extras) != "" {

cmd/yq/yq.go

@@ -0,0 +1,46 @@
+// SPDX-FileCopyrightText: Copyright The Lima Authors
+// SPDX-License-Identifier: Apache-2.0
+
+// SPDX-FileCopyrightText: Copyright (c) 2017 Mike Farah
+
+// This file has been adapted from https://github.com/mikefarah/yq/blob/v4.47.1/yq.go
+
+package yq
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+
+	command "github.com/mikefarah/yq/v4/cmd"
+)
+
+func main() {
+	cmd := command.New()
+	args := os.Args[1:]
+	_, _, err := cmd.Find(args)
+	if err != nil && args[0] != "__complete" {
+		// default command when nothing matches...
+		newArgs := []string{"eval"}
+		cmd.SetArgs(append(newArgs, os.Args[1:]...))
+	}
+	code := 0
+	if err := cmd.Execute(); err != nil {
+		code = 1
+	}
+	os.Exit(code)
+}
+
+// MaybeRunYQ runs as `yq` if the program name or first argument is `yq`.
+// Only returns to caller if os.Args doesn't contain a `yq` command.
+func MaybeRunYQ() {
+	progName := filepath.Base(os.Args[0])
+	progName = strings.TrimSuffix(progName, filepath.Ext(progName))
+	if progName == "yq" {
+		main()
+	}
+	if len(os.Args) > 1 && os.Args[1] == "yq" {
+		os.Args = os.Args[1:]
+		main()
+	}
+}