int_palindrome.go

package int_palindrome

func isPalindrome(n int) bool {
	reverse := 0

	for t := n; t > 0; t /= 10 {
		reverse *= 10
		reverse += t % 10
	}

	return reverse == n
}

int_palindrome_test.go

package int_palindrome

import "testing"

func TestZero(t *testing.T) {
	if !isPalindrome(0) {
		t.Error("zero is a palindrome")
	}
}

func TestOne(t *testing.T) {
	if !isPalindrome(1) {
		t.Error("1 is a palindrome")
	}
}

func TestLongerPalindromes(t *testing.T) {
	if n := 11; !isPalindrome(n) {
		t.Errorf("%d is a palindrome", n)
	}

	if n := 12344321; !isPalindrome(n) {
		t.Errorf("%d is a palindrome", n)
	}
}

func TestNonPalindromes(t *testing.T) {
	if n := 12; isPalindrome(n) {
		t.Errorf("%d is not a palindrome", n)
	}

	if n := 312344321; isPalindrome(n) {
		t.Errorf("%d is not a palindrome", n)
	}
}