go-gremlins/gremlins

/*
 * Copyright 2022 The Gremlins Authors
 *
 *    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 cmd

import (
    "context"
    "errors"
    "os"

    "github.com/MakeNowJust/heredoc"
    "github.com/spf13/cobra"

    "github.com/go-gremlins/gremlins/cmd/internal/flags"
    "github.com/go-gremlins/gremlins/internal/configuration"

    "github.com/go-gremlins/gremlins/internal/log"
)

const paramConfigFile = "config"

// Execute initialises a new Cobra root command (gremlins) with a custom version
// string used in the `-v` flag results.
func Execute(ctx context.Context, version string) error {
    rootCmd, err := newRootCmd(ctx, version)
    if err != nil {
        return err
    }

    return rootCmd.execute()
}

type gremlinsCmd struct {
    cmd *cobra.Command
}

func (gc gremlinsCmd) execute() error {
    var cfgFile string
    cobra.OnInitialize(func() {
        err := configuration.Init([]string{cfgFile})
        if err != nil {
            log.Errorf("initialization error: %s\n", err)
            os.Exit(1)
        }
    })
    gc.cmd.PersistentFlags().StringVar(&cfgFile, paramConfigFile, "", "override config file")

    return gc.cmd.Execute()
}

func newRootCmd(ctx context.Context, version string) (*gremlinsCmd, error) {
    if version == "" {
        return nil, errors.New("expected a version string")
    }

    cmd := &cobra.Command{
        Hidden:        true,
        SilenceUsage:  true,
        SilenceErrors: true,
        Use:           "gremlins",
        Short:         shortExplainer(),
        Version:       version,
    }

    uc, err := newUnleashCmd(ctx)
    if err != nil {
        return nil, err

    }
    cmd.AddCommand(uc.cmd)

    flag := &flags.Flag{Name: "silent", CfgKey: configuration.GremlinsSilentKey, Shorthand: "s", DefaultV: false, Usage: "suppress output and run in silent mode"}
    if err := flags.SetPersistent(cmd, flag); err != nil {
        return nil, err
    }

    return &gremlinsCmd{
        cmd: cmd,
    }, nil
}

func shortExplainer() string {
    return heredoc.Doc(`
        Gremlins is a mutation testing tool for Go projects, made with love by k3rn31 
        and friends.
    `)
}