net.conv: add a test for the nth16/nth32/nth64/htn16/htn32/htn64 functions

vlib/net/conv/conv_test.v

@@ -0,0 +1,44 @@
+import net.conv
+
+fn check<T>(f fn (a &T) T, finv fn (b &T) T, x T) {
+	a := f(x)
+	b := finv(a)
+	assert b == x
+	// eprintln('> x: ${x:10} | a: ${a:10} | b: ${b:10}')
+	$if little_endian {
+		assert a != b
+	}
+	$if big_endian {
+		assert a == b
+	}
+}
+
+fn test_htn64_nth64() {
+	assert 0 == conv.htn64(0)
+	assert 0 == conv.nth64(0)
+	assert 0xFFFF_FFFF_FFFF_FFFF == conv.nth64(0xFFFF_FFFF_FFFF_FFFF)
+	assert 0xFFFF_FFFF_FFFF_FFFF == conv.htn64(0xFFFF_FFFF_FFFF_FFFF)
+	for x in [u64(1), 2, 128, 65536, 2147483648] {
+		check(conv.htn64, conv.nth64, x)
+	}
+}
+
+fn test_htn32_nth32() {
+	assert 0 == conv.htn32(0)
+	assert 0 == conv.nth32(0)
+	assert 0xFFFF_FFFF == conv.nth32(0xFFFF_FFFF)
+	assert 0x0101_0101 == conv.htn32(0x0101_0101)
+	for x in [u32(1), 2, 128, 65536, 2147483648] {
+		check(conv.htn32, conv.nth32, x)
+	}
+}
+
+fn test_htn16_nth16() {
+	assert 0 == conv.htn16(0)
+	assert 0 == conv.nth16(0)
+	assert 0xFFFF == conv.nth16(0xFFFF)
+	assert 0x0101 == conv.htn16(0x0101)
+	for x in [u16(1), 2, 128, 65534] {
+		check(conv.htn16, conv.nth16, x)
+	}
+}