}

  public void testConcat() throws IOException {
    CharSource c1 = CharSource.wrap("abc");
    CharSource c2 = CharSource.wrap("");
    CharSource c3 = CharSource.wrap("de");

    String expected = "abcde";

    assertEquals(expected, CharSource.concat(ImmutableList.of(c1, c2, c3)).read());
    assertEquals(expected, CharSource.concat(c1, c2, c3).read());

		},
		// Test Case - 4.
		// Test case with AccessKey of length 2.
		{
			inputCredentialStr: generateCredentialStr(
				"^#",
				UTCNow().Format(yyyymmdd),
				"ABCD",
				"ABCD",
				"ABCD"),
			expectedCredentials: credentialHeader{},
			expectedErrCode:     ErrInvalidAccessKeyID,
		},
		// Test Case - 5.
		// Test case with invalid date format date.

		t.Fatalf("expect 4 abcd but got %s. r.w=%d, r.r=%d", rb.Bytes(nil), rb.w, rb.r)
	}

	// check empty or full
	if rb.IsEmpty() {
		t.Fatalf("expect IsEmpty is false but got true")
	}
	if rb.IsFull() {
		t.Fatalf("expect IsFull is false but got true")
	}

	// write 48 bytes, should full
	n, err = rb.Write([]byte(strings.Repeat("abcd", 12)))
	if err != nil {

func TestEvalSQLSubstring(t *testing.T) {
	evalCases := []struct {
		s           string
		startIdx    int
		length      int
		resExpected string
		errExpected error
	}{
		{"abcd", 1, 1, "a", nil},
		{"abcd", -1, 1, "a", nil},
		{"abcd", 999, 999, "", nil},
		{"", 999, 999, "", nil},
		{"测试abc", 1, 1, "测", nil},
		{"测试abc", 5, 5, "c", nil},
	}

	for i, tc := range evalCases {

		{bucketNames[1], objectNames[0], uploadIDs[3], 1, "abcd", "e2fc714c4727ee9395f324cd2e7f331f", int64(len("abcd")), "e2fc714c4727ee9395f324cd2e7f331f"},
		// Case 8-13.
		// Generating parts for different objects.

    assertEqualCharNodes(traverser.breadthFirst(charactersOf("acdb")), "acdb");
    assertEqualCharNodes(traverser.breadthFirst(charactersOf("db")), "db");
  }

  @Test
  public void forGraph_breadthFirst_multiGraph() {
    Traverser<Character> traverser = Traverser.forGraph(MULTI_GRAPH);
    assertEqualCharNodes(traverser.breadthFirst('a'), "abcd");

    assertEqualCharNodes(traverser.breadthFirst(charactersOf("acdb")), "acdb");
    assertEqualCharNodes(traverser.breadthFirst(charactersOf("db")), "db");
  }

  @Test
  public void forGraph_breadthFirst_multiGraph() {
    Traverser<Character> traverser = Traverser.forGraph(MULTI_GRAPH);
    assertEqualCharNodes(traverser.breadthFirst('a'), "abcd");

		if a != 1 || b != 2 || c != 3 || d != 4 {
			println("1# abcd: expected 1 2 3 4 got", a, b, c, d)
			os.Exit(1)
		}
	}
	// Test real closure.
	{
		x := 4
		gf = func(i int) (p int, q int, r int, s int) { return 1, i, 3, x }

		a, b, c, d := gf(2)

		if a != 1 || b != 2 || c != 3 || d != 4 {
			println("2# abcd: expected 1 2 3 4 got", a, b, c, d)
			os.Exit(1)
		}
	}
}

		{"", "", 0},
		{"", "abc", 0},
		{"abc", "", -1},
		{"abc", "abc", 0},
		{"d", "abcdefg", 3},
		{"nan", "banana", 2},
		{"pan", "anpanman", 2},
		{"nnaaman", "anpanmanam", -1},
		{"abcd", "abc", -1},
		{"abcd", "bcd", -1},
		{"bcd", "abcd", 1},
		{"abc", "acca", -1},
		{"aa", "aaa", 0},
		{"baa", "aaaaa", -1},
		{"at that", "which finally halts.  at that point", 22},
	}

	for _, tc := range testCases {

		commonPrefix string
	}{
		{[]string{"", ""}, ""},
		{[]string{"a", "b"}, ""},
		{[]string{"a", "a"}, "a"},
		{[]string{"a/", "a/"}, "a/"},
		{[]string{"abcd/", ""}, ""},
		{[]string{"abcd/foo/", "abcd/bar/"}, "abcd/"},
		{[]string{"abcd/foo/bar/", "abcd/foo/bar/zoo"}, "abcd/foo/bar/"},
	}

	for i, test := range testCases {
		foundPrefix := lcp(test.prefixes, true)
		if foundPrefix != test.commonPrefix {