github.com/rzurga/go-swagger@v0.28.1-0.20211109195225-5d1f453ffa3a/cmd/swagger/commands/internal/cmdtest/output.go (about)

     1  // Package cmdtest provides test utilities
     2  // to assert the output of CLI commands
     3  package cmdtest
     4  
     5  import (
     6  	"io"
     7  	"io/ioutil"
     8  	"os"
     9  	"strings"
    10  	"testing"
    11  
    12  	"github.com/stretchr/testify/assert"
    13  	"github.com/stretchr/testify/require"
    14  )
    15  
    16  // AssertReadersContent compares the contents from io.Readers, optionally stripping blanks
    17  func AssertReadersContent(t testing.TB, noBlanks bool, expected, actual io.Reader) bool {
    18  	e, err := ioutil.ReadAll(expected)
    19  	require.NoError(t, err)
    20  
    21  	a, err := ioutil.ReadAll(actual)
    22  	require.NoError(t, err)
    23  
    24  	var wants, got strings.Builder
    25  	_, _ = wants.Write(e)
    26  	_, _ = got.Write(a)
    27  
    28  	if noBlanks {
    29  		r := strings.NewReplacer(" ", "", "\t", "", "\n", "")
    30  		return assert.Equalf(t, r.Replace(wants.String()), r.Replace(got.String()), "expected:\n%s\ngot %s", wants.String(), got.String())
    31  	}
    32  	return assert.Equal(t, wants.String(), got.String())
    33  }
    34  
    35  // CatchStdOut captures the standard output from a runnable function.
    36  // You shouln't run this in parallel.
    37  func CatchStdOut(t testing.TB, runnable func() error) ([]byte, error) {
    38  	realStdout := os.Stdout
    39  	defer func() { os.Stdout = realStdout }()
    40  	r, fakeStdout, err := os.Pipe()
    41  	require.NoError(t, err)
    42  	os.Stdout = fakeStdout
    43  	e := runnable()
    44  	// need to close here, otherwise ReadAll never gets "EOF".
    45  	require.NoError(t, fakeStdout.Close())
    46  	newOutBytes, err := ioutil.ReadAll(r)
    47  	require.NoError(t, err)
    48  	require.NoError(t, r.Close())
    49  	return newOutBytes, e
    50  }