Added wc command (#24)

Fixes #22

commands/cat_test.go

@@ -3,9 +3,9 @@ package commands
 import (
  "testing"
 
+ "github.com/josephlewis42/honeyssh/core/vos/vostest"
  "github.com/spf13/afero"
  "github.com/stretchr/testify/assert"
- "github.com/josephlewis42/honeyssh/core/vos/vostest"
 )
 
 func TestCat(t *testing.T) {

commands/testdata/golden/TestWc/help.golden

@@ -0,0 +1,9 @@
+usage: wc [-c|-m] [-lw] [FILE...]
+Write the number of newlines, words, and bytes contained in each input file to the standard output.
+
+Flags:
+ -c, --c write the number of bytes in each file
+ -h, --help show this help and exit
+ -l, --l write the number of newlines in each file
+ -m, --m write the number of characters in each file
+ -w, --w write the number of words in each file

commands/testdata/golden/TestWc/missing.golden

@@ -0,0 +1 @@
+wc: open : open /does not exist.txt: file does not exist

commands/testdata/golden/TestWc/no-arg.golden

@@ -0,0 +1 @@
+wc: file already closed

commands/wc.go

@@ -0,0 +1,172 @@
+package commands
+
+import (
+ "fmt"
+ "io"
+ "unicode"
+
+ "github.com/josephlewis42/honeyssh/core/vos"
+)
+
+type wcCount struct {
+ bytes int
+ lines int
+ chars int
+ words int
+ name string
+
+ inSpace bool
+}
+
+func (w *wcCount) Write(data []byte) (int, error) {
+ for _, c := range data {
+ isFirstByte := w.bytes == 0
+ w.bytes++
+
+ // Assume UTF-8 characters. Bytes following the leading byte always
+ // have MSB of 0b10 indicating they're part of a previous character.
+ if c < 0b10000000 || c > 0b10111111 {
+ w.chars++
+ }
+
+ if c == '\n' {
+ w.lines++
+ }
+
+ if unicode.IsSpace(rune(c)) {
+ w.inSpace = true
+ } else {
+ if w.inSpace || isFirstByte {
+ w.words++
+ }
+ w.inSpace = false
+ }
+ }
+
+ return len(data), nil
+}
+
+func NewWcCount(name string, fd io.Reader) (*wcCount, error) {
+ var out wcCount
+ out.name = name
+
+ if _, err := io.Copy(&out, fd); err != nil {
+ return nil, err
+ }
+
+ return &out, nil
+}
+
+func (w *wcCount) Increment(other *wcCount) {
+ w.bytes += other.bytes
+ w.chars += other.chars
+ w.lines += other.lines
+ w.words += other.words
+}
+
+// Wc implements the POSIX command by the same name.
+// https://pubs.opengroup.org/onlinepubs/009695399/utilities/wc.html
+func Wc(virtOS vos.VOS) int {
+ cmd := &SimpleCommand{
+ Use: "wc [-c|-m] [-lw] [FILE...]",
+ Short: "Write the number of newlines, words, and bytes contained in each input file to the standard output.",
+ }
+
+ opts := cmd.Flags()
+ writeLines := opts.BoolLong("l", 'l', "write the number of newlines in each file")
+ writeWords := opts.BoolLong("w", 'w', "write the number of words in each file")
+ writeBytes := opts.BoolLong("c", 'c', "write the number of bytes in each file")
+ writeChars := opts.BoolLong("m", 'm', "write the number of characters in each file")
+
+ return cmd.RunE(virtOS, func() error {
+ args := opts.Args()
+
+ anyPicked := *writeLines || *writeWords || *writeBytes || *writeChars
+ nonePicked := !anyPicked
+
+ var cols []func(*wcCount) string
+
+ if *writeLines || nonePicked {
+ cols = append(cols, func(w *wcCount) string {
+ return fmt.Sprint(w.lines)
+ })
+ }
+ if *writeWords || nonePicked {
+ cols = append(cols, func(w *wcCount) string {
+ return fmt.Sprint(w.words)
+ })
+ }
+ if *writeBytes || nonePicked {
+ cols = append(cols, func(w *wcCount) string {
+ return fmt.Sprint(w.bytes)
+ })
+ }
+ if *writeChars {
+ cols = append(cols, func(w *wcCount) string {
+ return fmt.Sprint(w.chars)
+ })
+ }
+
+ displayCount := func(count *wcCount) {
+ for i, col := range cols {
+ if i != 0 {
+ fmt.Fprint(virtOS.Stdout(), " ")
+ }
+ fmt.Fprint(virtOS.Stdout(), col(count))
+ }
+ fmt.Fprintln(virtOS.Stdout())
+ }
+
+ writeCounts := func(countsList ...*wcCount) {
+ total := &wcCount{name: "total"}
+
+ for _, count := range countsList {
+ total.Increment(count)
+ displayCount(count)
+ }
+
+ if len(countsList) > 1 {
+ displayCount(total)
+ }
+ }
+
+ if len(args) == 0 {
+ count, err := NewWcCount("", virtOS.Stdin())
+ if err != nil {
+ return err
+ }
+ writeCounts(count)
+ return nil
+ }
+
+ cols = append(cols, func(w *wcCount) string {
+ return w.name
+ })
+
+ var counts []*wcCount
+ for _, path := range args {
+ fd, err := virtOS.Open(path)
+ if err != nil {
+ return err
+ }
+ defer fd.Close()
+
+ count, err := NewWcCount(path, fd)
+ if err != nil {
+ return err
+ }
+
+ counts = append(counts, count)
+ }
+
+ writeCounts(counts...)
+
+ return nil
+ })
+}
+
+var _ vos.ProcessFunc = Wc
+
+func init() {
+ addBinCmd("wc", Wc)
+}

commands/wc_test.go

@@ -0,0 +1,41 @@
+package commands
+
+import (
+ "testing"
+
+ "github.com/josephlewis42/honeyssh/core/vos/vostest"
+ "github.com/spf13/afero"
+ "github.com/stretchr/testify/assert"
+)
+
+func TestWc(t *testing.T) {
+ cases := goldenTestSuite{
+ "no-arg": {[]string{"wc"}},
+ "help": {[]string{"wc", "--help"}},
+ "missing": {[]string{"wc", "does not exist.txt"}},
+ }
+
+ cases.Run(t, Wc)
+}
+
+func TestWc_single_file(t *testing.T) {
+ cmd := vostest.Command(Wc, "wc", "/foo.txt")
+
+ // Test with missing file
+ {
+ assert.Nil(t, cmd.Run())
+
+ assert.NotEqual(t, 0, cmd.ExitStatus, "exit code")
+ }
+ {
+ // Create file and
+ helloWorld := []byte("Hello,\nworld !")
+ assert.Nil(t, afero.WriteFile(cmd.VOS, "/foo.txt", helloWorld, 0600))
+
+ out, err := cmd.CombinedOutput()
+
+ assert.Equal(t, 0, cmd.ExitStatus, "exit code")
+ assert.Nil(t, err)
+ assert.Equal(t, "1 3 14 /foo.txt\n", string(out))
+ }
+}