assertThat(Strings.commonPrefix("abc", "")).isEqualTo("");
    assertThat(Strings.commonPrefix("", "abc")).isEqualTo("");
    assertThat(Strings.commonPrefix("abcde", "xyz")).isEqualTo("");
    assertThat(Strings.commonPrefix("xyz", "abcde")).isEqualTo("");
    assertThat(Strings.commonPrefix("xyz", "abcxyz")).isEqualTo("");
    assertThat(Strings.commonPrefix("abc", "aaaaa")).isEqualTo("a");

			testRemaining{0, 0},
		},
	}, {
		maker: makeSparse{makeReg{5, "abcde"}, sparseHoles{{2, 3}}, 8},
		tests: []testFnc{
			testRemaining{8, 5},
			testWrite{"ab\x00\x00\x00cde", 8, nil},
			testWrite{"a", 0, ErrWriteTooLong},
			testRemaining{0, 0},
		},
	}, {
		maker: makeSparse{makeReg{5, "abcde"}, sparseHoles{{2, 3}}, 8},
		tests: []testFnc{

    assertThat(Strings.commonPrefix("abc", "")).isEqualTo("");
    assertThat(Strings.commonPrefix("", "abc")).isEqualTo("");
    assertThat(Strings.commonPrefix("abcde", "xyz")).isEqualTo("");
    assertThat(Strings.commonPrefix("xyz", "abcde")).isEqualTo("");
    assertThat(Strings.commonPrefix("xyz", "abcxyz")).isEqualTo("");
    assertThat(Strings.commonPrefix("abc", "aaaaa")).isEqualTo("a");

	// Output: "64 bytes or fewer"
}

func ExampleBuffer_Len() {
	var b bytes.Buffer
	b.Grow(64)
	b.Write([]byte("abcde"))
	fmt.Printf("%d", b.Len())
	// Output: 5
}

func ExampleBuffer_Next() {
	var b bytes.Buffer
	b.Grow(64)
	b.Write([]byte("abcde"))
	fmt.Printf("%s\n", b.Next(2))
	fmt.Printf("%s\n", b.Next(2))
	fmt.Printf("%s", b.Next(2))
	// Output:
	// ab
	// cd
	// e
}

			testRead{0, "", io.EOF},
		},
	}, {
		maker: makeSparse{makeReg{"abcde", 5}, sparseDatas{{0, 2}, {5, 3}}, 8},
		tests: []testFnc{
			testRemaining{8, 5},
			testRead{3, "ab\x00", nil},
			testRead{10, "\x00\x00cde", io.EOF},
			testRemaining{0, 0},
		},
	}, {
		maker: makeSparse{makeReg{"abcde", 5}, sparseDatas{{0, 2}, {5, 3}}, 8},
		tests: []testFnc{
			testRemaining{8, 5},

			keys:     []string{"etag", "md5"},
			want:     map[string]string{"content-type": "application/octet-stream", "x-amz-storage-class": "STANDARD"},
		},
		{
			name:     "2",
			metadata: map[string]string{"content-type": "application/octet-stream", "etag": "de75a98baf2c6aef435b57dd0fc33c86", "x-amz-storage-class": "REDUCED_REDUNDANCY", "md5sum": "abcde"},
			keys:     []string{"etag", "md5sum"},

  }

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

    String expected = "abcde";

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

    return onPatternInternal(Platform.compilePattern(separatorPattern));
  }

  /**
   * Returns a splitter that divides strings into pieces of the given length. For example, {@code
   * Splitter.fixedLength(2).split("abcde")} returns an iterable containing {@code ["ab", "cd",
   * "e"]}. The last piece can be smaller than {@code length} but will never be empty.
   *

    //     the smaller of these blocks with the far end of the other one. That leaves us with a
    //     smaller version of the same problem.
    //     Say we are rotating abcdefgh by 5. We start with abcde|fgh. The smaller block is [fgh]:
    //     [abc]de|[fgh] -> [fgh]de|[abc]. Now [fgh] is in the right place, but we need to swap [de]
    //     with [abc]: fgh[de]|a[bc] -> fgh[bc]|a[de]. Now we need to swap [a] with [bc]:

    builder.append("C");
    assertThat(iterator.next()).isEqualTo("C");
    assertFalse(iterator.hasNext());
  }

  public void testFixedLengthSimpleSplit() {
    String simple = "abcde";
    Iterable<String> letters = Splitter.fixedLength(2).split(simple);
    assertThat(letters).containsExactly("ab", "cd", "e").inOrder();
  }

  public void testFixedLengthSplitEqualChunkLength() {