assertFile(Relay.PREFIX_CLEAN, 10L, metadata.size, "abcdefghij", metadata)
  }

  @Test
  fun readFromFile() {
    val upstream = Buffer()
    upstream.writeUtf8("abcdefghijklmnopqrst")
    val relay = edit(file, upstream, metadata, 5)
    val source1 = relay.newSource()!!.buffer()
    val source2 = relay.newSource()!!.buffer()
    assertThat(source1.readUtf8(10)).isEqualTo("abcdefghij")

	}{
		{
			name:               "lowerAscii",
			expr:               "'ABCDEFGHIJ abcdefghij'.lowerAscii()",
			expectEsimatedCost: checker.CostEstimate{Min: 3, Max: 3},
			expectRuntimeCost:  3,
		},
		{
			name:               "lowerAsciiEquals",
			expr:               "'ABCDEFGHIJ abcdefghij'.lowerAscii() == 'abcdefghij ABCDEFGHIJ'.lowerAscii()",
			expectEsimatedCost: checker.CostEstimate{Min: 7, Max: 9},

		{10, 20, []string{"0123456789", "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", "klmn"}},         // a whole read
		{0, 5, []string{"\x00\x00\x00\x00\x0056789", "abcdefghij", "klmn"}},                          // start
		{12, 24, []string{"0123456789", "ab\x00\x00\x00\x00\x00\x00\x00\x00", "\x00\x00\x00\x00"}},   // end
	}
	p := make([]byte, 10)
	for _, test := range tests {

	{"αβδ", "ΑΒΔ", true},
	{"abc", "xyz", false},
	{"abc", "XYZ", false},
	{"abcdefghijk", "abcdefghijX", false},
	{"abcdefghijk", "abcdefghij\u212A", true},
	{"abcdefghijK", "abcdefghij\u212A", true},
	{"abcdefghijkz", "abcdefghij\u212Ay", false},
	{"abcdefghijKz", "abcdefghij\u212Ay", false},
	{"1", "2", false},
	{"utf-8", "US-ASCII", false},
}

func TestEqualFold(t *testing.T) {

	{0xaeef2a50, 0xa9421b7, "abcdefgh", "crc\x01ʇ\x91M\xed\x82\xcd\x11", "crc\x01wB\x84\x81\x92\xc8\n1"},
	{0x8da988af, 0x2ddc99fc, "abcdefghi", "crc\x01ʇ\x91M\xed\x82\xcd\x11", "crc\x01wB\x84\x81\x92\xc8\n1"},
	{0x3981703a, 0xe6599437, "abcdefghij", "crc\x01ʇ\x91M\x85\x87\xd8e", "crc\x01wB\x84\x81\xc4P֗"},
	{0x6b9cdfe7, 0xb2cc01fe, "Discard medicine more than two years old.", "crc\x01ʇ\x91M\xfd\xe5\xc2J", "crc\x01wB\x84\x81S\"(\xe0"},

	{"αβδ", "ΑΒΔ", true},
	{"abc", "xyz", false},
	{"abc", "XYZ", false},
	{"abcdefghijk", "abcdefghijX", false},
	{"abcdefghijk", "abcdefghij\u212A", true},
	{"abcdefghijK", "abcdefghij\u212A", true},
	{"abcdefghijkz", "abcdefghij\u212Ay", false},
	{"abcdefghijKz", "abcdefghij\u212Ay", false},
}

func TestEqualFold(t *testing.T) {
	for _, tt := range EqualFoldTests {

	}

	// Clean up the arena.
	a.Free()
	GC()
	GC()
}

func TestUserArenaCloneString(t *testing.T) {
	a := NewUserArena()

	// A static string (not on heap or arena)
	var s = "abcdefghij"

	// Create a byte slice in the arena, initialize it with s
	var b []byte
	a.Slice(&b, len(s))
	copy(b, s)

	// Create a string as using the same memory as the byte slice, hence in

	{"72399361da6a7754fec986dca5b7cbaf1c810a28ded4abaf56b2106d06cb78b0", "abcdefghij", "sha\x03j\t\xe6g\xbbg\xae\x85<n\xf3r\xa5O\xf5:Q\x0eR\u007f\x9b\x05h\x8c\x1f\x83٫[\xe0\xcd\x19abcde\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00...

	{"d68c19a0a345b7eab78d5e11e991c026ec60db63", "abcdefghij", "sha\x01gE#\x01\xef\u036b\x89\x98\xba\xdc\xfe\x102Tv\xc3\xd2\xe1\xf0abcde\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\...

	},
	{
		"f809423cbb25e81a2a64aecee2cd5fdc7d91d5db583901fbf1db3116",
		"abcdefghij",