Merge pull request #2 from tiburon-777/hw02_unpack_string

Hw02 unpack string

hw02_unpack_string/README.md

@@ -1,4 +1,5 @@
 ## Домашнее задание №2 «Распаковка строки»
+[![Build Status](https://travis-ci.com/tiburon-777/HW_OTUS.svg?branch=master)](https://travis-ci.com/tiburon-777/HW_OTUS)
 
 Необходимо написать Go функцию, осуществляющую примитивную распаковку строки,
 содержащую повторяющиеся символы/руны, например:

hw02_unpack_string/go.mod

@@ -1,4 +1,4 @@
-module github.com/fixme_my_friend/hw02_unpack_string
+module github.com/tiburon-777/HW_OTUS/hw02_unpack_string
 
 go 1.14
 

hw02_unpack_string/go.sum

@@ -5,6 +5,7 @@ github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZN
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.5.0 h1:DMOzIV76tmoDNE9pX6RSN0aDtCYeCg5VueieJaAo1uw=
 github.com/stretchr/testify v1.5.0/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v2 v2.2.2 h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=

hw02_unpack_string/unpack.go

@@ -2,11 +2,44 @@ package hw02_unpack_string //nolint:golint,stylecheck
 
 import (
 	"errors"
+	"strconv"
+	"strings"
+	"unicode"
 )
 
 var ErrInvalidString = errors.New("invalid string")
 
-func Unpack(_ string) (string, error) {
-	// Place your code here
-	return "", nil
+const slash = '\\'
+
+func Unpack(str string) (string, error) {
+	var b strings.Builder
+	temp := []rune(str)
+	for i := 0; i < len(temp); i++ {
+		switch {
+		// Ловим паттерн [\][letter][digit]
+		case temp[i] == slash && i < len(temp)-2 && unicode.IsLetter(temp[i+1]) && unicode.IsDigit(temp[i+2]):
+			c, _ := strconv.Atoi(string(temp[i+2]))
+			b.WriteString(strings.Repeat(string(slash)+string(temp[i+1]), c))
+			i += 2
+		// Ловим паттерн [\][digit или \][digit]
+		case temp[i] == slash && i < len(temp)-2 && (unicode.IsDigit(temp[i+1]) || temp[i+1] == slash) && unicode.IsDigit(temp[i+2]):
+			c, _ := strconv.Atoi(string(temp[i+2]))
+			b.WriteString(strings.Repeat(string(temp[i+1]), c))
+			i += 2
+		// Ловим паттерн [\][digit или \]
+		case temp[i] == slash && i < len(temp)-1 && (unicode.IsDigit(temp[i+1]) || temp[i+1] == slash):
+			b.WriteRune(temp[i+1])
+			i++
+		case unicode.IsLetter(temp[i]) && i < len(temp)-1 && unicode.IsDigit(temp[i+1]):
+			c, _ := strconv.Atoi(string(temp[i+1]))
+			b.WriteString(strings.Repeat(string(temp[i]), c))
+			i++
+			// Ловим паттерн [letter]...
+		case unicode.IsLetter(temp[i]):
+			b.WriteRune(temp[i])
+		default:
+			return "", ErrInvalidString
+		}
+	}
+	return b.String(), nil
 }

hw02_unpack_string/unpack_test.go

@@ -45,6 +45,29 @@ func TestUnpack(t *testing.T) {
 			input:    "aaa0b",
 			expected: "aab",
 		},
+		{
+			input:    "fftcwerv ervev sva5scs",
+			expected: "",
+			err:      ErrInvalidString,
+		},
+		{
+			input:    `||\||(8^`,
+			expected: "",
+			err:      ErrInvalidString,
+		},
+		{
+			input:    "ис3куРАкс2еу",
+			expected: "иссскуРАкссеу",
+		},
+		{
+			input:    "рлрплотчрв",
+			expected: "рлрплотчрв",
+		},
+		{
+			input:    string([]rune{1234, 67, 45, 2324, 899, 353, 2345, 65}),
+			expected: "",
+			err:      ErrInvalidString,
+		},
 	} {
 		result, err := Unpack(tst.input)
 		require.Equal(t, tst.err, err)
@@ -53,7 +76,6 @@ func TestUnpack(t *testing.T) {
 }
 
 func TestUnpackWithEscape(t *testing.T) {
-	t.Skip() // Remove if task with asterisk completed
 
 	for _, tst := range [...]test{
 		{
@@ -72,6 +94,11 @@ func TestUnpackWithEscape(t *testing.T) {
 			input:    `qwe\\\3`,
 			expected: `qwe\3`,
 		},
+		{
+			input:    `3\\cds\4`,
+			expected: ``,
+			err:      ErrInvalidString,
+		},
 	} {
 		result, err := Unpack(tst.input)
 		require.Equal(t, tst.err, err)