add some tests

internal/helpers_test.go

@@ -0,0 +1,83 @@
+package internal
+
+import (
+	"reflect"
+	"testing"
+)
+
+func Test_parseDNSToCheck(t *testing.T) {
+	type args struct {
+		data string
+	}
+	tests := []struct {
+		name string
+		args args
+		want []string
+	}{
+		{
+			name: "test parsing",
+			args: args{
+				data: "word1,word2,",
+			},
+			want: []string{"word1", "word2"},
+		},
+		{
+			name: "test parsing with spaces",
+			args: args{
+				data: " word1, word2 ",
+			},
+			want: []string{"word1", "word2"},
+		},
+		{
+			name: "test parsing with empty word",
+			args: args{
+				data: " word1, word2 ,",
+			},
+			want: []string{"word1", "word2"},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := parseDNSToCheck(tt.args.data); !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("parseDNSToCheck() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
+func TestContains(t *testing.T) {
+	type args[T comparable] struct {
+		haystack []T
+		needle   T
+	}
+	type testCase[T comparable] struct {
+		name string
+		args args[T]
+		want bool
+	}
+	tests := []testCase[string]{
+		{
+			name: "yes",
+			args: args[string]{
+				haystack: []string{"w1", "w2"},
+				needle:   "w1",
+			},
+			want: true,
+		},
+		{
+			name: "no",
+			args: args[string]{
+				haystack: []string{"w1", "w2"},
+				needle:   "w3",
+			},
+			want: false,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := Contains(tt.args.haystack, tt.args.needle); got != tt.want {
+				t.Errorf("Contains() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}