github.com/beanworks/dcm@v0.0.0-20230726194615-49d2d0417e04/src/cmd_test.go (about)

     1  package main
     2  
     3  import (
     4  	"bytes"
     5  	"errors"
     6  	"fmt"
     7  	"os"
     8  	"os/exec"
     9  	"reflect"
    10  	"testing"
    11  
    12  	"github.com/stretchr/testify/assert"
    13  )
    14  
    15  // ========== Mocked command executer as test helpers for Cmd ==========
    16  
    17  // Test helper functions and command mock
    18  func helperCommand(t *testing.T, s ...string) *exec.Cmd {
    19  	cs := []string{"-test.run=TestHelperProcess", "--"}
    20  	cs = append(cs, s...)
    21  	cmd := exec.Command(os.Args[0], cs...)
    22  	cmd.Env = []string{"GO_WANT_HELPER_PROCESS=1"}
    23  	return cmd
    24  }
    25  
    26  // TestHelperProcess isn't a real test. It's used as a helper process
    27  // for TestParameterRun.
    28  func TestHelperProcess(*testing.T) {
    29  	if os.Getenv("GO_WANT_HELPER_PROCESS") != "1" {
    30  		return
    31  	}
    32  	defer os.Exit(0)
    33  
    34  	args := os.Args
    35  	for len(args) > 0 {
    36  		if args[0] == "--" {
    37  			args = args[1:]
    38  			break
    39  		}
    40  		args = args[1:]
    41  	}
    42  	if len(args) == 0 {
    43  		fmt.Fprintf(os.Stderr, "No command\n")
    44  		os.Exit(2)
    45  	}
    46  
    47  	cmd, args := args[0], args[1:]
    48  	switch cmd {
    49  	case "echo":
    50  		iargs := []interface{}{}
    51  		for _, s := range args {
    52  			iargs = append(iargs, s)
    53  		}
    54  		fmt.Println(iargs...)
    55  	default:
    56  		fmt.Fprintf(os.Stderr, "Unknown command %q\n", cmd)
    57  		os.Exit(2)
    58  	}
    59  }
    60  
    61  // ========== Here starts the real tests for Cmd ==========
    62  
    63  func TestCmdExec(t *testing.T) {
    64  	name := os.Args[0]
    65  	args := []string{"-test.run=TestHelperProcess", "--", "echo"}
    66  
    67  	c := &Cmd{}
    68  	c.Exec(name, args...)
    69  
    70  	assert.Equal(t, name, c.name)
    71  	assert.Equal(t, args, c.args)
    72  	assert.Equal(t, "*exec.Cmd", reflect.TypeOf(c.cmd).String())
    73  }
    74  
    75  func TestCmdSetStdin(t *testing.T) {
    76  	c := &Cmd{}
    77  	c.SetStdin(os.Stdin)
    78  
    79  	assert.IsType(t, os.Stdin, c.stdin)
    80  }
    81  
    82  func TestCmdSetStderr(t *testing.T) {
    83  	c := &Cmd{}
    84  	c.SetStderr(os.Stderr)
    85  
    86  	assert.IsType(t, os.Stderr, c.stderr)
    87  }
    88  
    89  func TestCmdSetdir(t *testing.T) {
    90  	c := &Cmd{}
    91  	c.cmd = helperCommand(t, "echo")
    92  
    93  	assert.Equal(t, "", c.cmd.Dir)
    94  	c.Setdir("/test/dir")
    95  	assert.Equal(t, "/test/dir", c.cmd.Dir)
    96  }
    97  
    98  func TestCmdSetenvAndGetenv(t *testing.T) {
    99  	c := &Cmd{}
   100  
   101  	assert.Equal(t, []string{}, c.Getenv())
   102  
   103  	c.cmd = helperCommand(t, "echo")
   104  
   105  	assert.Equal(t, []string{"GO_WANT_HELPER_PROCESS=1"}, c.cmd.Env)
   106  	assert.Equal(t, []string{"GO_WANT_HELPER_PROCESS=1"}, c.Getenv())
   107  
   108  	c.Setenv([]string{"GO_WANT_HELPER_PROCESS=1", "foo=bar", "baz=qux"})
   109  
   110  	assert.Equal(t, []string{"GO_WANT_HELPER_PROCESS=1", "foo=bar", "baz=qux"}, c.cmd.Env)
   111  	assert.Equal(t, []string{"GO_WANT_HELPER_PROCESS=1", "foo=bar", "baz=qux"}, c.Getenv())
   112  }
   113  
   114  func TestCmdRun(t *testing.T) {
   115  	var out bytes.Buffer
   116  
   117  	NewCmd().
   118  		SetStdout(&out).
   119  		Setcmd(helperCommand(t, "echo", "foo", "bar")).
   120  		Run()
   121  
   122  	assert.Equal(t, "foo bar\n", out.String())
   123  }
   124  
   125  func TestCmdOut(t *testing.T) {
   126  	out, _ := NewCmd().
   127  		Setcmd(helperCommand(t, "echo", "baz", "qux")).
   128  		Out()
   129  
   130  	assert.Equal(t, "baz qux\n", string(out))
   131  }
   132  
   133  func TestCmdFormatOutput(t *testing.T) {
   134  	c := NewCmd()
   135  	fixture := []byte("foobar\n")
   136  
   137  	assert.Equal(t, "foobar", c.FormatOutput(fixture))
   138  }
   139  
   140  func TestCmdFormatError(t *testing.T) {
   141  	c := NewCmd()
   142  	err := errors.New("foobar")
   143  	out := []byte("bazqux")
   144  
   145  	assert.Equal(t, errors.New("foobar: bazqux"), c.FormatError(err, out))
   146  }