Add lab 4 - Numeronym (anz-bank#640)

Add lab 4 - Numeronym

04_numeronym/alextmz/main.go

@@ -0,0 +1,34 @@
+package main
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"strconv"
+	"unicode/utf8"
+)
+
+var out io.Writer = os.Stdout
+
+func main() {
+	fmt.Fprintln(out, numeronyms("accessibility", "Kubernetes", "abc"))
+}
+
+func numeronyms(vals ...string) []string {
+	r := make([]string, len(vals))
+	for k, v := range vals {
+		r[k] = numeronym(v)
+	}
+	return r
+}
+
+func numeronym(s string) string {
+	numrunes := utf8.RuneCountInString(s)
+	if numrunes < 4 {
+		return s
+	}
+	firstrune, _ := utf8.DecodeRuneInString(s)
+	lastrune, _ := utf8.DecodeLastRuneInString(s)
+
+	return string(firstrune) + strconv.Itoa(numrunes-2) + string(lastrune)
+}

04_numeronym/alextmz/main_test.go

@@ -0,0 +1,67 @@
+package main
+
+import (
+	"bytes"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestNumeronym(t *testing.T) {
+	var tests = map[string]struct {
+		arg  string
+		want string
+	}{
+		"empty string":               {"", ""},
+		"single string of 1 element": {"a", "a"},
+		"single long string":         {"abracadabra", "a9a"},
+		"unicode at the start":       {"🤪bracadabra", "🤪9a"},
+		"unicode in the middle":      {"abra🤪🤪🤪abra", "a9a"},
+		"unicode in the end":         {"abracadabr🤪", "a9🤪"},
+		"1 poo":                      {"💩", "💩"},
+		"2 poos":                     {"💩💩", "💩💩"},
+		"3 poos":                     {"💩💩💩", "💩💩💩"},
+		"4 poos":                     {"💩💩💩💩", "💩2💩"},
+	}
+
+	for name, tt := range tests {
+		test := tt
+		t.Run(name, func(t *testing.T) {
+			got := numeronym(test.arg)
+			assert.Equal(t, test.want, got)
+		})
+	}
+}
+
+func TestNumeronyms(t *testing.T) {
+	var tests = map[string]struct {
+		arg  []string
+		want []string
+	}{
+		"empty string": {
+			[]string{""},
+			[]string{""}},
+		"mixed strings": {
+			[]string{"", "alakazam", "hocuspocus", "mumbojumbo", "💩💩💩💩"},
+			[]string{"", "a6m", "h8s", "m8o", "💩2💩"}},
+	}
+
+	for name, tt := range tests {
+		test := tt
+		t.Run(name, func(t *testing.T) {
+			got := numeronyms(test.arg...)
+			assert.Equal(t, test.want, got)
+		})
+	}
+}
+
+func TestMain(t *testing.T) {
+	want := "[a11y K8s abc]\n"
+	t.Run("main test", func(t *testing.T) {
+		var buf bytes.Buffer
+		out = &buf
+		main()
+		got := buf.String()
+		assert.Equal(t, got, want)
+	})
+}