Implemented Lab4 numeronym and test cases (#542)

* Implemented Lab4 numeronym and test cases

04_numeronym/sirigithub/main.go

@@ -0,0 +1,25 @@
+package main
+
+import (
+	"fmt"
+	"io"
+	"os"
+)
+
+var out io.Writer = os.Stdout
+
+func numeronyms(vals ...string) []string {
+	result := make([]string, len(vals))
+	for i, val := range vals {
+		r := []rune(val)
+		runeLength := len(r)
+		if runeLength > 3 {
+			val = fmt.Sprintf("%c%d%c", r[0], runeLength-2, r[runeLength-1])
+		}
+		result[i] = val
+	}
+	return result
+}
+func main() {
+	fmt.Fprintln(out, numeronyms("accessibility", "Kubernetes", "abc"))
+}

04_numeronym/sirigithub/main_test.go

@@ -0,0 +1,46 @@
+package main
+
+import (
+	"bytes"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestMainOutput(t *testing.T) {
+	var buf bytes.Buffer
+	out = &buf
+	main()
+	actual := buf.String()
+	expected := "[a11y K8s abc]\n"
+	assert.Equal(t, expected, actual)
+
+}
+func TestNumeronyms(t *testing.T) {
+	tests := []struct {
+		description string
+		input,
+		expected []string
+	}{
+		{description: "Empty string", input: []string{""}, expected: []string{""}},
+		{description: "Short strings", input: []string{"sss", "ab", "a"}, expected: []string{"sss", "ab", "a"}},
+		{description: "Alphanumeric string", input: []string{"sss1245sdfg"}, expected: []string{"s9g"}},
+		{description: "Back slashes and spaces", input: []string{"sss\\", "A long string with spaces"},
+			expected: []string{"s2\\", "A23s"}},
+		{description: "Emoji strings", input: []string{"😄🐷🙈🐷🏃😄", "😄🏃😄"},
+			expected: []string{"😄4😄", "😄🏃😄"}},
+		{description: "Unicode Strings", input: []string{"日本語日本語", "äö߀’üüüöäßß"},
+			expected: []string{"日4語", "ä10ß"}},
+		{description: "Strings with special characters",
+			input:    []string{"a##67&a$", "**(]]"},
+			expected: []string{"a6$", "*3]"}},
+	}
+	for _, test := range tests {
+		test := test
+		t.Run(test.description, func(t *testing.T) {
+			actual := numeronyms(test.input...)
+			expected := test.expected
+			assert.Equal(t, actual, expected, "actual %v but expected %v", actual, expected)
+		})
+	}
+}