package notes

import (

"bytes"

"io"

"os/exec"

"strings"

"testing"

)

func TestPagerCmdParseFail(t *testing.T) {

if _, err := StartPagerWriter("'foo", io.Discard); err == nil || !strings.Contains(err.Error(), "Cannot parsing") {

t.Fatal("Unexpected error", err)

}

}

func TestPagerStartErrorPropagation(t *testing.T) {

var errs []error

w, err := StartPagerWriter("/path/to/bin/unknown", io.Discard)

errs = append(errs, err)

_, err = w.Write([]byte("hello"))

errs = append(errs, err)

err = w.Wait()

errs = append(errs, err)

for i, err := range errs {

if err == nil || !strings.Contains(err.Error(), "Cannot start pager command") {

t.Fatal("Unexpected error", err, "at index", i)

}

}

}

func TestPagerRunGivenCommand(t *testing.T) {

if _, err := exec.LookPath("less"); err != nil {

t.Skip("`less` command is necessary to run this test")

}

var buf bytes.Buffer

w, err := StartPagerWriter("less -X", &buf)

if err != nil {

t.Fatal(err)

}

if w.Cmdline != "less -X" {

t.Fatal("Cmdline is not set correctly:", w.Cmdline)

}

if _, err := w.Write([]byte("hello, world!")); err != nil {

t.Fatal(err)

}

if err := w.Wait(); err != nil {

t.Fatal(err)

}

have := buf.String()

if have != "hello, world!" {

t.Fatal("Stdin to pager is not piped correctly. `cat` output:", have)

}

}

func TestPagerRunGivenMultipleArguments(t *testing.T) {

var buf bytes.Buffer

w, err := StartPagerWriter("echo hello 'and goodbye' \"world\"", &buf)

if err != nil {

t.Fatal(err)

}

if err := w.Wait(); err != nil {

t.Fatal(err)

}

have := buf.String()

if have != "hello and goodbye world\n" {

t.Fatal("Multiple arguments in pagerCmd was not parsed as intended. `echo` output:", have)

}

}

func TestPagerCommandExitFailure(t *testing.T) {

w, err := StartPagerWriter("false", io.Discard)

if err != nil {

t.Fatal(err)

}

if err := w.Wait(); err == nil {

t.Fatal("Error did not occur")

}

}