# Test this inner rbyd data-structure

[cases.test_rbyd_commit_fetch]
in = 'lfs.c'
defines.ERASE_VALUE = [0xff, 0x00, 0x1b, -1]
code = '''
    lfs_t lfs;
    lfs_init(&lfs, cfg) => 0;

    lfs_rbyd_t rbyd_init = {
        .block = 0,
        .trunk = 0,
        .noff = 0,
        .rev = 1,
        .crc = 0,
        .count = 0,
        .erased = true,
    };

    // try an empty commit
    lfs_rbyd_t rbyd = rbyd_init;
    lfs_bd_erase(&lfs, rbyd.block) => 0;
    lfs_rbyd_commit(&lfs, &rbyd, NULL) => 0;
    lfs_rbyd_fetch(&lfs, &rbyd, rbyd.block, NULL) => 0;

    // commit with one attribute
    rbyd = rbyd_init;
    lfs_bd_erase(&lfs, rbyd.block) => 0;
    lfs_rbyd_commit(&lfs, &rbyd,
            LFS_MKRATTR(GSTATE, 1, 0, &(uint32_t){0xaaaaaaaa}, 4, NULL)) => 0;
    lfs_rbyd_fetch(&lfs, &rbyd, rbyd.block, NULL) => 0;

    // commit with two attributes
    rbyd = rbyd_init;
    lfs_bd_erase(&lfs, rbyd.block) => 0;
    lfs_rbyd_commit(&lfs, &rbyd,
            LFS_MKRATTR(GSTATE, 1, 0, &(uint32_t){0xaaaaaaaa}, 4,
            LFS_MKRATTR(GSTATE, 2, 0, &(uint32_t){0xbbbbbbbb}, 4,
            NULL))) => 0;
    lfs_rbyd_fetch(&lfs, &rbyd, rbyd.block, NULL) => 0;
'''

[cases.test_rbyd_multi_commit_fetch]
in = 'lfs.c'
defines.ERASE_VALUE = [0xff, 0x00, 0x1b, -1]
code = '''
    lfs_t lfs;
    lfs_init(&lfs, cfg) => 0;

    lfs_rbyd_t rbyd_init = {
        .block = 0,
        .trunk = 0,
        .noff = 0,
        .rev = 1,
        .crc = 0,
        .count = 0,
        .erased = true,
    };

    // try an empty commit
    lfs_rbyd_t rbyd = rbyd_init;
    lfs_bd_erase(&lfs, rbyd.block) => 0;
    lfs_rbyd_commit(&lfs, &rbyd, NULL) => 0;
    lfs_rbyd_fetch(&lfs, &rbyd, rbyd.block, NULL) => 0;

    // commit with one attribute
    rbyd = rbyd_init;
    lfs_bd_erase(&lfs, rbyd.block) => 0;
    lfs_rbyd_commit(&lfs, &rbyd, NULL) => 0;
    lfs_rbyd_commit(&lfs, &rbyd,
            LFS_MKRATTR(GSTATE, 1, 0, &(uint32_t){0xaaaaaaaa}, 4, NULL)) => 0;
    lfs_rbyd_fetch(&lfs, &rbyd, rbyd.block, NULL) => 0;

    // commit with two attributes
    rbyd = rbyd_init;
    lfs_bd_erase(&lfs, rbyd.block) => 0;
    lfs_rbyd_commit(&lfs, &rbyd,
            LFS_MKRATTR(GSTATE, 1, 0, &(uint32_t){0xaaaaaaaa}, 4, NULL)) => 0;
    lfs_rbyd_commit(&lfs, &rbyd,
            LFS_MKRATTR(GSTATE, 2, 0, &(uint32_t){0xbbbbbbbb}, 4, NULL)) => 0;
    lfs_rbyd_fetch(&lfs, &rbyd, rbyd.block, NULL) => 0;
'''

[cases.test_rbyd_commit_lookup]
in = 'lfs.c'
defines.ERASE_VALUE = [0xff, 0x00, 0x1b, -1]
code = '''
    lfs_t lfs;
    lfs_init(&lfs, cfg) => 0;

    lfs_rbyd_t rbyd_init = {
        .block = 0,
        .trunk = 0,
        .noff = 0,
        .rev = 1,
        .crc = 0,
        .count = 0,
        .erased = true,
    };

    // try an empty commit
    lfs_rbyd_t rbyd = rbyd_init;
    lfs_bd_erase(&lfs, rbyd.block) => 0;
    lfs_rbyd_commit(&lfs, &rbyd, NULL) => 0;

    // TODO test in-between lookups for consistently finding the next >= tag?
    lfs_off_t off;
    lfs_size_t size;
    lfs_rbyd_lookup(&lfs, &rbyd, 0, &off, &size)
            => LFS_ERR_NOENT;
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 1, 0), &off, &size)
            => LFS_ERR_NOENT;

    lfs_rbyd_fetch(&lfs, &rbyd, rbyd.block, NULL) => 0;
    lfs_rbyd_lookup(&lfs, &rbyd, 0, &off, &size)
            => LFS_ERR_NOENT;
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 1, 0), &off, &size)
            => LFS_ERR_NOENT;

    // commit with one attribute
    rbyd = rbyd_init;
    lfs_bd_erase(&lfs, rbyd.block) => 0;
    lfs_rbyd_commit(&lfs, &rbyd,
            LFS_MKRATTR(GSTATE, 1, 0, &(uint32_t){0xaaaaaaaa}, 4, NULL)) => 0;

    lfs_rbyd_lookup(&lfs, &rbyd, 0, &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 1, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 2, 0), &off, &size)
            => LFS_ERR_NOENT;

    lfs_rbyd_fetch(&lfs, &rbyd, rbyd.block, NULL) => 0;
    lfs_rbyd_lookup(&lfs, &rbyd, 0, &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 1, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 2, 0), &off, &size)
            => LFS_ERR_NOENT;

    // commit with two attributes
    rbyd = rbyd_init;
    lfs_bd_erase(&lfs, rbyd.block) => 0;
    lfs_rbyd_commit(&lfs, &rbyd,
            LFS_MKRATTR(GSTATE, 1, 0, &(uint32_t){0xaaaaaaaa}, 4,
            LFS_MKRATTR(GSTATE, 2, 0, &(uint32_t){0xbbbbbbbb}, 4,
            NULL))) => 0;

    lfs_rbyd_lookup(&lfs, &rbyd, 0, &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 1, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 2, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 2, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 3, 0), &off, &size)
            => LFS_ERR_NOENT;

    lfs_rbyd_fetch(&lfs, &rbyd, rbyd.block, NULL) => 0;
    lfs_rbyd_lookup(&lfs, &rbyd, 0, &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 1, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 2, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 2, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 3, 0), &off, &size)
            => LFS_ERR_NOENT;
'''

# TODO we should make sure lookup always returns <= the requested tag, 
# this may require fixing in lfs_rbyd_commit to make sure the weights lean
# one way
[cases.test_rbyd_multi_commit_lookup]
in = 'lfs.c'
defines.ERASE_VALUE = [0xff, 0x00, 0x1b, -1]
code = '''
    lfs_t lfs;
    lfs_init(&lfs, cfg) => 0;

    lfs_rbyd_t rbyd_init = {
        .block = 0,
        .trunk = 0,
        .noff = 0,
        .rev = 1,
        .crc = 0,
        .count = 0,
        .erased = true,
    };

    // try an empty commit
    lfs_rbyd_t rbyd = rbyd_init;
    lfs_bd_erase(&lfs, rbyd.block) => 0;
    lfs_rbyd_commit(&lfs, &rbyd, NULL) => 0;

    lfs_off_t off;
    lfs_size_t size;
    lfs_rbyd_lookup(&lfs, &rbyd, 0, &off, &size)
            => LFS_ERR_NOENT;
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 1, 0), &off, &size)
            => LFS_ERR_NOENT;

    lfs_rbyd_fetch(&lfs, &rbyd, rbyd.block, NULL) => 0;
    // TODO move these extra checks (for 0, in-between, enoent) to other tests
    lfs_rbyd_lookup(&lfs, &rbyd, 0, &off, &size)
            => LFS_ERR_NOENT;
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 1, 0), &off, &size)
            => LFS_ERR_NOENT;

    // commit with one attribute
    rbyd = rbyd_init;
    lfs_bd_erase(&lfs, rbyd.block) => 0;
    lfs_rbyd_commit(&lfs, &rbyd,
            LFS_MKRATTR(GSTATE, 1, 0, &(uint32_t){0xaaaaaaaa}, 4, NULL)) => 0;

    lfs_rbyd_lookup(&lfs, &rbyd, 0, &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 1, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 2, 0), &off, &size)
            => LFS_ERR_NOENT;

    lfs_rbyd_fetch(&lfs, &rbyd, rbyd.block, NULL) => 0;
    lfs_rbyd_lookup(&lfs, &rbyd, 0, &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 1, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 2, 0), &off, &size)
            => LFS_ERR_NOENT;

    // commit with two attributes
    rbyd = rbyd_init;
    lfs_bd_erase(&lfs, rbyd.block) => 0;
    lfs_rbyd_commit(&lfs, &rbyd,
            LFS_MKRATTR(GSTATE, 1, 0, &(uint32_t){0xaaaaaaaa}, 4, NULL)) => 0;
    lfs_rbyd_commit(&lfs, &rbyd,
            LFS_MKRATTR(GSTATE, 2, 0, &(uint32_t){0xbbbbbbbb}, 4, NULL)) => 0;

    lfs_rbyd_lookup(&lfs, &rbyd, 0, &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 1, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 2, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 2, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 3, 0), &off, &size)
            => LFS_ERR_NOENT;

    lfs_rbyd_fetch(&lfs, &rbyd, rbyd.block, NULL) => 0;
    lfs_rbyd_lookup(&lfs, &rbyd, 0, &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 1, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 2, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 2, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 3, 0), &off, &size)
            => LFS_ERR_NOENT;
'''

# [cases.test_rbyd_commit_fetchmatch]
# [cases.test_rbyd_multi_commit_fetchmatch]

[cases.test_rbyd_bifoliate]
in = 'lfs.c'
defines.ERASE_VALUE = [0xff, 0x00, 0x1b, -1]
code = '''
    lfs_t lfs;
    lfs_init(&lfs, cfg) => 0;

    lfs_rbyd_t rbyd_init = {
        .block = 0,
        .trunk = 0,
        .noff = 0,
        .rev = 1,
        .crc = 0,
        .count = 0,
        .erased = true,
    };

    // create a split in the leaves
    //          <b
    //    =>  .-'|
    // 1      1  2
    lfs_rbyd_t rbyd = rbyd_init;
    lfs_bd_erase(&lfs, rbyd.block) => 0;
    lfs_rbyd_commit(&lfs, &rbyd,
            LFS_MKRATTR(GSTATE, 1, 0, &(uint32_t){0xaaaaaaaa}, 4,
            LFS_MKRATTR(GSTATE, 2, 0, &(uint32_t){0xbbbbbbbb}, 4, NULL))) => 0;

    lfs_rbyd_fetch(&lfs, &rbyd, rbyd.block, NULL) => 0;
    lfs_off_t off;
    lfs_size_t size;
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 1, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 2, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 2, 0);

    // split the other direction
    //          >b
    //    =>  .-'|
    // 2      2  1
    rbyd = rbyd_init;
    lfs_bd_erase(&lfs, rbyd.block) => 0;
    lfs_rbyd_commit(&lfs, &rbyd,
            LFS_MKRATTR(GSTATE, 2, 0, &(uint32_t){0xaaaaaaaa}, 4,
            LFS_MKRATTR(GSTATE, 1, 0, &(uint32_t){0xbbbbbbbb}, 4, NULL))) => 0;

    lfs_rbyd_fetch(&lfs, &rbyd, rbyd.block, NULL) => 0;
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 1, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 2, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 2, 0);
'''

[cases.test_rbyd_bflips]
in = 'lfs.c'
defines.ERASE_VALUE = [0xff, 0x00, 0x1b, -1]
code = '''
    lfs_t lfs;
    lfs_init(&lfs, cfg) => 0;

    lfs_rbyd_t rbyd_init = {
        .block = 0,
        .trunk = 0,
        .noff = 0,
        .rev = 1,
        .crc = 0,
        .count = 0,
        .erased = true,
    };

    // ignore a black edge 
    //   <b           <b
    // .-'|  =>  .----'|
    // 1  2      1  2  2
    lfs_rbyd_t rbyd = rbyd_init;
    lfs_bd_erase(&lfs, rbyd.block) => 0;
    lfs_rbyd_commit(&lfs, &rbyd,
            LFS_MKRATTR(GSTATE, 1, 0, &(uint32_t){0xaaaaaaaa}, 4,
            LFS_MKRATTR(GSTATE, 2, 0, &(uint32_t){0xbbbbbbbb}, 4,
            LFS_MKRATTR(GSTATE, 2, 0, &(uint32_t){0xcccccccc}, 4, NULL)))) => 0;

    lfs_rbyd_fetch(&lfs, &rbyd, rbyd.block, NULL) => 0;
    lfs_off_t off;
    lfs_size_t size;
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 1, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 2, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 2, 0);

    // flip a black edge
    //   <b           >b
    // .-'|  =>     .-'|
    // 1  2      1  2  1
    rbyd = rbyd_init;
    lfs_bd_erase(&lfs, rbyd.block) => 0;
    lfs_rbyd_commit(&lfs, &rbyd,
            LFS_MKRATTR(GSTATE, 1, 0, &(uint32_t){0xaaaaaaaa}, 4,
            LFS_MKRATTR(GSTATE, 2, 0, &(uint32_t){0xbbbbbbbb}, 4,
            LFS_MKRATTR(GSTATE, 1, 0, &(uint32_t){0xcccccccc}, 4, NULL)))) => 0;

    lfs_rbyd_fetch(&lfs, &rbyd, rbyd.block, NULL) => 0;
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 1, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 2, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 2, 0);
'''

[cases.test_rbyd_trifoliate]
in = 'lfs.c'
defines.ERASE_VALUE = [0xff, 0x00, 0x1b, -1]
code = '''
    lfs_t lfs;
    lfs_init(&lfs, cfg) => 0;

    lfs_rbyd_t rbyd_init = {
        .block = 0,
        .trunk = 0,
        .noff = 0,
        .rev = 1,
        .crc = 0,
        .count = 0,
        .erased = true,
    };

    // without a flip
    //                <r
    //           .----'|
    //   <b  =>  |    <b
    // .-'|      |  .-'|
    // 1  2      1  2  3
    lfs_rbyd_t rbyd = rbyd_init;
    lfs_bd_erase(&lfs, rbyd.block) => 0;
    lfs_rbyd_commit(&lfs, &rbyd,
            LFS_MKRATTR(GSTATE, 1, 0, &(uint32_t){0xaaaaaaaa}, 4,
            LFS_MKRATTR(GSTATE, 2, 0, &(uint32_t){0xbbbbbbbb}, 4,
            LFS_MKRATTR(GSTATE, 3, 0, &(uint32_t){0xcccccccc}, 4, NULL)))) => 0;

    lfs_rbyd_fetch(&lfs, &rbyd, rbyd.block, NULL) => 0;
    lfs_off_t off;
    lfs_size_t size;
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 1, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 2, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 2, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 3, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 3, 0);

    // with a flip
    //                >r
    //              .-'|
    //   <b  =>     | >b
    // .-'|      .--|-'|
    // 2  3      2  3  1
    rbyd = rbyd_init;
    lfs_bd_erase(&lfs, rbyd.block) => 0;
    lfs_rbyd_commit(&lfs, &rbyd,
            LFS_MKRATTR(GSTATE, 2, 0, &(uint32_t){0xaaaaaaaa}, 4,
            LFS_MKRATTR(GSTATE, 3, 0, &(uint32_t){0xbbbbbbbb}, 4,
            LFS_MKRATTR(GSTATE, 1, 0, &(uint32_t){0xcccccccc}, 4, NULL)))) => 0;

    lfs_rbyd_fetch(&lfs, &rbyd, rbyd.block, NULL) => 0;
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 1, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 2, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 2, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 3, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 3, 0);
'''


[cases.test_rbyd_rflips]
in = 'lfs.c'
defines.ERASE_VALUE = [0xff, 0x00, 0x1b, -1]
code = '''
    lfs_t lfs;
    lfs_init(&lfs, cfg) => 0;

    lfs_rbyd_t rbyd_init = {
        .block = 0,
        .trunk = 0,
        .noff = 0,
        .rev = 1,
        .crc = 0,
        .count = 0,
        .erased = true,
    };

    // ignore a red edge and black edge
    //      <r              <r
    // .----'|      .-------'|
    // |    <b  =>  |       <b
    // |  .-'|      |  .----'|
    // 1  2  3      1  2  3  3
    lfs_rbyd_t rbyd = rbyd_init;
    lfs_bd_erase(&lfs, rbyd.block) => 0;
    lfs_rbyd_commit(&lfs, &rbyd,
            LFS_MKRATTR(GSTATE, 1, 0, &(uint32_t){0xaaaaaaaa}, 4,
            LFS_MKRATTR(GSTATE, 2, 0, &(uint32_t){0xbbbbbbbb}, 4,
            LFS_MKRATTR(GSTATE, 3, 0, &(uint32_t){0xcccccccc}, 4,
            LFS_MKRATTR(GSTATE, 3, 0, &(uint32_t){0xdddddddd}, 4, NULL))))) => 0;

    lfs_rbyd_fetch(&lfs, &rbyd, rbyd.block, NULL) => 0;
    lfs_off_t off;
    lfs_size_t size;
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 1, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 2, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 2, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 3, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 3, 0);

    // ignore a red edge, flip a black edge
    //      <r              <r
    // .----'|      .-------'|
    // |    <b  =>  |       >b
    // |  .-'|      |     .-'|
    // 1  2  3      1  2  3  2
    rbyd = rbyd_init;
    lfs_bd_erase(&lfs, rbyd.block) => 0;
    lfs_rbyd_commit(&lfs, &rbyd,
            LFS_MKRATTR(GSTATE, 1, 0, &(uint32_t){0xaaaaaaaa}, 4,
            LFS_MKRATTR(GSTATE, 2, 0, &(uint32_t){0xbbbbbbbb}, 4,
            LFS_MKRATTR(GSTATE, 3, 0, &(uint32_t){0xcccccccc}, 4, 
            LFS_MKRATTR(GSTATE, 2, 0, &(uint32_t){0xdddddddd}, 4, NULL))))) => 0;

    lfs_rbyd_fetch(&lfs, &rbyd, rbyd.block, NULL) => 0;
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 1, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 2, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 2, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 3, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 3, 0);

    // flip a red edge and black edge
    //      <r              >r
    // .----'|            .-'|
    // |    <b  =>        | >b
    // |  .-'|         .--|-'|
    // 1  2  3      1  2  3  1
    rbyd = rbyd_init;
    lfs_bd_erase(&lfs, rbyd.block) => 0;
    lfs_rbyd_commit(&lfs, &rbyd,
            LFS_MKRATTR(GSTATE, 1, 0, &(uint32_t){0xaaaaaaaa}, 4,
            LFS_MKRATTR(GSTATE, 2, 0, &(uint32_t){0xbbbbbbbb}, 4,
            LFS_MKRATTR(GSTATE, 3, 0, &(uint32_t){0xcccccccc}, 4, 
            LFS_MKRATTR(GSTATE, 1, 0, &(uint32_t){0xdddddddd}, 4, NULL))))) => 0;

    lfs_rbyd_fetch(&lfs, &rbyd, rbyd.block, NULL) => 0;
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 1, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 2, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 2, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 3, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 3, 0);

    // flip a red edge, ignore a black edge
    //      <r              >r
    //    .-'|      .-------'|
    //    | >b  =>  |       >b
    // .--|-'|      |     .-'|
    // 3  1  2      3  1  2  1
    rbyd = rbyd_init;
    lfs_bd_erase(&lfs, rbyd.block) => 0;
    lfs_rbyd_commit(&lfs, &rbyd,
            LFS_MKRATTR(GSTATE, 3, 0, &(uint32_t){0xaaaaaaaa}, 4,
            LFS_MKRATTR(GSTATE, 1, 0, &(uint32_t){0xbbbbbbbb}, 4,
            LFS_MKRATTR(GSTATE, 2, 0, &(uint32_t){0xcccccccc}, 4, 
            LFS_MKRATTR(GSTATE, 1, 0, &(uint32_t){0xdddddddd}, 4, NULL))))) => 0;

    lfs_rbyd_fetch(&lfs, &rbyd, rbyd.block, NULL) => 0;
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 1, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 1, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 2, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 2, 0);
    lfs_rbyd_lookup(&lfs, &rbyd, LFS_MKRTAG(GSTATE, 3, 0), &off, &size)
            => LFS_MKRTAG(GSTATE, 3, 0);
'''