def test_long_addresses(self):
"""Tests predecessor tree with len-64 addresses
"""
self.tree = PredecessorTree()
address_a = \
'ca978112ca1bbdcafac231b39a23dc4da786eff8147c4e72b9807785afee48bb'
address_b = \
'3e23e8160039594a33894f6564e1b1348bbd7a0088d42c4acb73eeaed59c009d'
self.add_readers({address_a: 'txn1', address_b: 'txn2'})
# Set a writer for address_a.
self.set_writer(address_a, 'txn1')
# Verify address_a now contains txn1 as the writer, with no
# readers set.
# Verify address_b didn't change when address_a was modified.
# Set a writer for a prefix of address_b.
address_c = address_b[0:4]
self.set_writer(address_c, 'txn3')
# Verify address_c now contains txn3 as the writer, with
# no readers set and no children.
# Verify address_a didn't change when address_c was modified.
# Verify address_b now returns None
# Add readers for address_a, address_b
self.add_readers({address_a: 'txn1', address_b: 'txn2'})
# Verify address_c now contains txn3 as the writer, with
# no readers set and 'e8' as a child.
self.assert_rw_preds_at_addresses({
address_a: ({'txn1'}, {'txn1'}),
address_b: ({'txn3'}, {'txn3', 'txn2'}),
address_c: ({'txn3'}, {'txn3', 'txn2'}),
})
self.assert_rw_count(2, 2)
def setUp(self):
self.tree = PredecessorTree(token_size=1)
class TestPredecessorTree(unittest.TestCase):
'''
With an empty tree initialized in setUp, the predecessor tree
tests generally follow this pattern (repeated several times):
1) Add some readers or writers. In most cases, a diagram
will be given in comments to show what the tree should
look like after the additions.
2) Assert the readers, writers, and children at all addresses
in the tree (using assert_rwc_at_addresses). Possibly also
assert (using assert_no_nodes_at_addresses) that nodes don't
exist at certain addresses (this is normally done after
setting a writer).
3) Assert the total count of readers and writers in the tree
(using assert_rw_count). This ensures that nothing is in the
tree that shouldn't be there.
4) Assert the read and write predecessors for various addresses
(using assert_rw_preds_at_addresses).
Although the default token size for the predecessor tree is 2,
1 is used for most tests because it makes for more natural examples.
'''
def setUp(self):
self.tree = PredecessorTree(token_size=1)
def tearDown(self):
self.tree = None
def test_predecessor_tree(self):
'''Tests basic predecessor tree functions
This test is intended to show the evolution of a tree
over the course of normal use. Apart from testing, it
can also be used as a reference example.
Readers and writers are added in the following steps:
1) Add some readers.
2) Add readers at addresses that are initial segments
of existing node addresses.
3) Add a writer in the middle of the tree.
4) Add readers to existing nodes.
5) Add a writer to a new node.
6) Add writers in the middle of the tree.
7) Add readers to upper nodes.
8) Add readers to nodes with writers.
9) Add readers to new top nodes.
10) Add writer to top node.
11) Add readers to upper nodes, then add writers.
12) Add writer to top node, then add reader.
13) Add writer to root
'''
# 1) Add some readers.
self.add_readers({
'radix': 1,
'radish': 2,
'radon': 3,
'razzle': 4,
'rustic': 5
})
# ROOT:
# r:
# a:
# d:
# o:
# n: Readers: [3]
# i:
# x: Readers: [1]
# s:
# h: Readers: [2]
# z:
# z:
# l:
# e: Readers: [4]
# u:
# s:
# t:
# i:
# c: Readers: [5]
self.assert_rwc_at_addresses({
'r': ([], None, {'a', 'u'}),
'ra': ([], None, {'z', 'd'}),
'rad': ([], None, {'o', 'i'}),
'radi': ([], None, {'s', 'x'}),
'radix': ([1], None, {}),
'radish': ([2], None, {}),
'radon': ([3], None, {}),
'razzle': ([4], None, {}),
'ru': ([], None, {'s'}),
'rust': ([], None, {'i'}),
'rustic': ([5], None, {}),
})
self.assert_rw_count(5, 0)
self.assert_rw_preds_at_addresses({
'r': ({}, {1, 2, 3, 4, 5}),
'rad': ({}, {1, 2, 3}),
'radi': ({}, {1, 2}),
'radix': ({}, {1}),
})
# 2) Add readers at addresses that are initial segments
# of existing node addresses.
self.add_readers({'rad': 6, 'rust': 7})
# ROOT:
# r:
# a:
# d: Readers: [6]
# o:
# n: Readers: [3]
# i:
# x: Readers: [1]
# s:
# h: Readers: [2]
# z:
# z:
# l:
# e: Readers: [4]
# u:
# s:
# t: Readers: [7]
# i:
# c: Readers: [5]
self.assert_rwc_at_addresses({
'r': ([], None, {'a', 'u'}),
'ra': ([], None, {'z', 'd'}),
'rad': ([6], None, {'o', 'i'}),
'radi': ([], None, {'s', 'x'}),
'radix': ([1], None, {}),
'radish': ([2], None, {}),
'radon': ([3], None, {}),
'razzle': ([4], None, {}),
'ru': ([], None, {'s'}),
'rust': ([7], None, {'i'}),
'rustic': ([5], None, {}),
})
self.assert_rw_count(7, 0)
self.assert_rw_preds_at_addresses({
'ra': ({}, {1, 2, 3, 4, 6}),
'ru': ({}, {5, 7}),
})
# 3) Add a writer in the middle of the tree.
self.set_writer('radi', 8)
# ROOT:
# r:
# u:
# s:
# t: Readers: [7]
# i:
# c: Readers: [5]
# a:
# d: Readers: [6]
# o:
# n: Readers: [3]
# i: Writer: 8
# z:
# z:
# l:
# e: Readers: [4]
self.assert_no_nodes_at_addresses('radix', 'radish')
self.assert_rwc_at_addresses({
'r': ([], None, {'a', 'u'}),
'ra': ([], None, {'z', 'd'}),
'rad': ([6], None, {'o', 'i'}),
'radi': ([], 8, {}),
'radon': ([3], None, {}),
'razzle': ([4], None, {}),
'ru': ([], None, {'s'}),
'rust': ([7], None, {'i'}),
'rustic': ([5], None, {}),
})
self.assert_rw_count(5, 1)
self.assert_rw_preds_at_addresses({
'rad': ({8}, {3, 6, 8}),
'radi': ({8}, {6, 8}),
'radical': ({8}, {6, 8}),
})
# 4) Add readers to existing nodes.
self.add_readers({
'rad': 9,
'radi': 10,
'radio': 11,
'radon': 12,
'rust': 13
})
# ROOT:
# r:
# u:
# s:
# t: Readers: [7, 13]
# i:
# c: Readers: [5]
# a:
# d: Readers: [6, 9]
# o:
# n: Readers: [3, 12]
# i: Writer: 8 Readers: [10]
# o: Readers: [11]
# z:
# z:
# l:
# e: Readers: [4]
self.assert_rwc_at_addresses({
'r': ([], None, {'a', 'u'}),
'ra': ([], None, {'z', 'd'}),
'rad': ([6, 9], None, {'o', 'i'}),
'radi': ([10], 8, {'o'}),
'radio': ([11], None, {}),
'radon': ([3, 12], None, {}),
'razzle': ([4], None, {}),
'ru': ([], None, {'s'}),
'rust': ([7, 13], None, {'i'}),
'rustic': ([5], None, {}),
})
self.assert_rw_count(10, 1)
self.assert_rw_preds_at_addresses({
'rad': ({8}, {6, 9, 10, 8, 11, 3, 12}),
'ru': ({}, {7, 13, 5}),
})
# 5) Add a writer to a new node.
self.set_writer('radii', 14)
# ROOT:
# r:
# u:
# s:
# t: Readers: [7, 13]
# i:
# c: Readers: [5]
# a:
# d: Readers: [6, 9]
# o:
# n: Readers: [3, 12]
# i: Writer: 8 Readers: [10]
# o: Readers: [11]
# i: Writer: 14
# z:
# z:
# l:
# e: Readers: [4]
self.assert_rwc_at_addresses({
'r': ([], None, {'a', 'u'}),
'ra': ([], None, {'z', 'd'}),
'rad': ([6, 9], None, {'o', 'i'}),
'radi': ([10], 8, {'o', 'i'}),
'radii': ([], 14, {}),
'radio': ([11], None, {}),
'radon': ([3, 12], None, {}),
'razzle': ([4], None, {}),
'ru': ([], None, {'s'}),
'rust': ([7, 13], None, {'i'}),
'rustic': ([5], None, {}),
})
self.assert_rw_count(10, 2)
self.assert_rw_preds_at_addresses({
'radi': ({8, 14}, {6, 9, 10, 8, 14, 11}),
'radii': ({14}, {6, 9, 10, 14}),
'radio': ({8}, {6, 9, 10, 8, 11}),
})
# 6) Add writers in the middle of the tree.
self.set_writers({'rust': 15, 'rad': 16})
# ROOT:
# r:
# u:
# s:
# t: Writer: 15
# a:
# d: Writer: 16
# z:
# z:
# l:
# e: Readers: [4]
self.assert_no_nodes_at_addresses('radi', 'radii', 'radio', 'radon',
'rustic')
self.assert_rwc_at_addresses({
'r': ([], None, {'a', 'u'}),
'ra': ([], None, {'z', 'd'}),
'rad': ([], 16, {}),
'razzle': ([4], None, {}),
'ru': ([], None, {'s'}),
'rust': ([], 15, {}),
})
self.assert_rw_count(1, 2)
self.assert_rw_preds_at_addresses({
'r': ({16, 15}, {16, 4, 15}),
'ru': ({15}, {15}),
'rust': ({15}, {15}),
'rustic': ({15}, {15}),
})
# 7) Add readers to upper nodes.
self.add_readers({
'r': 17,
'ra': 18,
'ru': 19,
})
# ROOT:
# r: Readers: [17]
# u: Readers: [19]
# s:
# t: Writer: 15
# a: Readers: [18]
# d: Writer: 16
# z:
# z:
# l:
# e: Readers: [4]
self.assert_rwc_at_addresses({
'r': ([17], None, {'a', 'u'}),
'ra': ([18], None, {'z', 'd'}),
'rad': ([], 16, {}),
'razzle': ([4], None, {}),
'ru': ([19], None, {'s'}),
'rust': ([], 15, {}),
})
self.assert_rw_count(4, 2)
self.assert_rw_preds_at_addresses({
'r': ({15, 16}, {17, 19, 15, 18, 16, 4}),
'ru': ({15}, {17, 19, 15}),
})
# 8) Add readers to nodes with writers.
self.add_readers({'rad': 20, 'rust': 21})
# ROOT:
# r: Readers: [17]
# u: Readers: [19]
# s:
# t: Writer: 15 Readers: [21]
# a: Readers: [18]
# d: Writer: 16 Readers: [20]
# z:
# z:
# l:
# e: Readers: [4]
self.assert_rwc_at_addresses({
'': ([], None, {'r'}),
'r': ([17], None, {'a', 'u'}),
'ra': ([18], None, {'z', 'd'}),
'rad': ([20], 16, {}),
'razzle': ([4], None, {}),
'ru': ([19], None, {'s'}),
'rust': ([21], 15, {}),
})
self.assert_rw_count(6, 2)
self.assert_rw_preds_at_addresses({
'': ({16, 15}, {17, 18, 20, 16, 4, 19, 21, 15}),
'rad': ({16}, {17, 18, 20, 16}),
'rust': ({15}, {17, 19, 21, 15}),
})
# 9) Add readers to new top nodes.
self.add_readers({
's': 22,
't': 23,
})
# ROOT:
# t: Readers: [23]
# s: Readers: [22]
# r: Readers: [17]
# u: Readers: [19]
# s:
# t: Writer: 15 Readers: [21]
# a: Readers: [18]
# d: Writer: 16 Readers: [20]
# z:
# z:
# l:
# e: Readers: [4]
self.assert_rwc_at_addresses({
'': ([], None, {'r', 's', 't'}),
'r': ([17], None, {'a', 'u'}),
'ra': ([18], None, {'z', 'd'}),
'rad': ([20], 16, {}),
'razzle': ([4], None, {}),
'ru': ([19], None, {'s'}),
'rust': ([21], 15, {}),
's': ([22], None, {}),
't': ([23], None, {}),
})
self.assert_rw_count(8, 2)
self.assert_rw_preds_at_addresses({
's': ({}, {22}),
't': ({}, {23}),
'r': ({16, 15}, {17, 18, 20, 16, 4, 19, 21, 15}),
})
# 10) Add writer to top node.
self.set_writer('s', 24)
# ROOT:
# t: Readers: [23]
# s: Writer: 24
# r: Readers: [17]
# u: Readers: [19]
# s:
# t: Writer: 15 Readers: [21]
# a: Readers: [18]
# d: Writer: 16 Readers: [20]
# z:
# z:
# l:
# e: Readers: [4]
self.assert_rwc_at_addresses({
'r': ([17], None, {'a', 'u'}),
'ra': ([18], None, {'z', 'd'}),
'rad': ([20], 16, {}),
'razzle': ([4], None, {}),
'ru': ([19], None, {'s'}),
'rust': ([21], 15, {}),
's': ([], 24, {}),
't': ([23], None, {}),
})
self.assert_rw_count(7, 3)
self.assert_rw_preds_at_addresses({
's': ({24}, {24}),
't': ({}, {23}),
'r': ({16, 15}, {17, 18, 20, 16, 4, 19, 21, 15}),
})
# 11) Add readers to upper nodes, then add writers.
self.add_readers({
'ra': 25,
'ru': 26,
})
self.set_writers({
'ra': 27,
'ru': 28,
})
# ROOT:
# t: Readers: [23]
# s: Writer: 24
# r: Readers: [17]
# u: Writer: 28
# a: Writer: 27
self.assert_rwc_at_addresses({
'r': ([17], None, {'a', 'u'}),
'ra': ([], 27, {}),
'ru': ([], 28, {}),
's': ([], 24, {}),
't': ([23], None, {}),
})
self.assert_no_nodes_at_addresses(
'rad',
'razzle',
'rust',
)
self.assert_rw_preds_at_addresses({
'r': ({27, 28}, {17, 27, 28}),
'ra': ({27}, {17, 27}),
'rad': ({27}, {17, 27}),
})
# 12) Add writer to top node, then add reader.
self.set_writer('r', 29)
self.add_reader('r', 30)
# ROOT:
# t: Readers: [23]
# s: Writer: 24
# r: Writer: 29 Readers: [30]
self.assert_rwc_at_addresses({
'': ([], None, {'r', 's', 't'}),
'r': ([30], 29, {}),
's': ([], 24, {}),
't': ([23], None, {}),
})
self.assert_no_nodes_at_addresses(
'ra',
'ru',
)
self.assert_rw_count(2, 2)
self.assert_rw_preds_at_addresses({
'r': ({29}, {30, 29}),
'roger': ({29}, {30, 29}),
'ebert': ({}, {}),
})
# 13) Add writer to root
self.set_writer('', 0)
# ROOT: Writer: 0
self.assert_rwc_at_addresses({'': ([], 0, {})})
self.assert_no_nodes_at_addresses('r', 's', 't')
self.assert_rw_count(0, 1)
self.assert_rw_preds_at_addresses({
'': ({0}, {0}),
'r': ({0}, {0}),
's': ({0}, {0}),
'rabbit': ({0}, {0}),
})
def test_initial_segment_addresses(self):
'''Tests addresses with and without common initial segments
'''
expected = (
('c', 1),
('ca', 2),
('cat', 3),
)
for address, val in expected:
self.set_writer(address, val)
self.add_reader(address, val)
# ROOT:
# c: Writer: 1 Readers: [1]
# a: Writer: 2 Readers: [2]
# t: Writer: 3 Readers: [3]
self.assert_rwc_at_addresses({
'': ([], None, {'c'}),
'c': ([1], 1, {'a'}),
'ca': ([2], 2, {'t'}),
'cat': ([3], 3, {}),
})
self.assert_rw_count(3, 3)
# 'cath' isn't on the tree, so it should have
# the same predecessors as 'cat'
self.assert_rw_preds_at_addresses({
'': ({1, 2, 3}, {1, 2, 3}),
'c': ({1, 2, 3}, {1, 2, 3}),
'ca': ({2, 3}, {1, 2, 3}),
'cat': ({3}, {1, 2, 3}),
'cath': ({3}, {1, 2, 3}),
})
# add reader and writer at an address with a common initial segment
self.set_writer('carp', 4)
self.add_reader('carp', 4)
# ROOT:
# c: Writer: 1 Readers: [1]
# a: Writer: 2 Readers: [2]
# r:
# p: Writer: 4 Readers: [4]
# t: Writer: 3 Readers: [3]
self.assert_rwc_at_addresses({
'': ([], None, {'c'}),
'c': ([1], 1, {'a'}),
'ca': ([2], 2, {'t', 'r'}),
'cat': ([3], 3, {}),
'carp': ([4], 4, {}),
})
self.assert_rw_count(4, 4)
self.assert_rw_preds_at_addresses({
'': ({1, 2, 3, 4}, {1, 2, 3, 4}),
'c': ({1, 2, 3, 4}, {1, 2, 3, 4}),
'ca': ({2, 3, 4}, {1, 2, 3, 4}),
'cat': ({3}, {1, 2, 3}),
'cath': ({3}, {1, 2, 3}),
'carp': ({4}, {1, 2, 4}),
})
# add reader and writer at an address with no common initial segment
self.set_writer('dog', 5)
self.add_reader('dog', 5)
# ROOT:
# c: Writer: 1 Readers: [1]
# a: Writer: 2 Readers: [2]
# r:
# p: Writer: 4 Readers: [4]
# t: Writer: 3 Readers: [3]
# d:
# o:
# g: Writer: 5 Readers: [5]
self.assert_rwc_at_addresses({
'': ([], None, {'c', 'd'}),
'c': ([1], 1, {'a'}),
'ca': ([2], 2, {'t', 'r'}),
'cat': ([3], 3, {}),
'carp': ([4], 4, {}),
'dog': ([5], 5, {}),
})
self.assert_rw_count(5, 5)
self.assert_rw_preds_at_addresses({
'': ({1, 2, 3, 4, 5}, {1, 2, 3, 4, 5}),
'c': ({1, 2, 3, 4}, {1, 2, 3, 4}),
'ca': ({2, 3, 4}, {1, 2, 3, 4}),
'cat': ({3}, {1, 2, 3}),
'cath': ({3}, {1, 2, 3}),
'carp': ({4}, {1, 2, 4}),
'dog': ({5}, {5}),
})
# check predecessors of an address that isn't on the tree at all
self.assert_rw_preds_at_addresses({
'yak': ({}, {}),
})
# add readers to root and check again
self.add_reader('', 6)
self.add_reader('', 7)
# ROOT: Readers: [6, 7]
# c: Writer: 1 Readers: [1]
# a: Writer: 2 Readers: [2]
# r:
# p: Writer: 4 Readers: [4]
# t: Writer: 3 Readers: [3]
# d:
# o:
# g: Writer: 5 Readers: [5]
self.assert_rwc_at_addresses({
'': ([6, 7], None, {'c', 'd'}),
'c': ([1], 1, {'a'}),
'ca': ([2], 2, {'t', 'r'}),
'cat': ([3], 3, {}),
'carp': ([4], 4, {}),
'dog': ([5], 5, {}),
})
self.assert_rw_count(7, 5)
self.assert_rw_preds_at_addresses({
'': ({1, 2, 3, 4, 5}, {1, 2, 3, 4, 5, 6, 7}),
'c': ({1, 2, 3, 4}, {1, 2, 3, 4, 6, 7}),
'ca': ({2, 3, 4}, {1, 2, 3, 4, 6, 7}),
'cat': ({3}, {1, 2, 3, 6, 7}),
'cath': ({3}, {1, 2, 3, 6, 7}),
'carp': ({4}, {1, 2, 4, 6, 7}),
'dog': ({5}, {5, 6, 7}),
'yak': ({}, {6, 7}),
})
def test_add_writers_to_same_node(self):
'''Adds a series of writers one after the other
to a single node, verifying after each new writer
that there is nothing else at that node and that
there is just one writer in the whole tree.
'''
# Set writer num at 'address'
for num in range(10):
self.set_writer('plum', num)
# ROOT:
# p:
# l:
# u:
# m: Writer: ,num
self.assert_rwc_at_addresses({
'': ([], None, {'p'}),
'p': ([], None, {'l'}),
'pl': ([], None, {'u'}),
'plu': ([], None, {'m'}),
'plum': ([], num, {}),
})
self.assert_rw_count(0, 1)
self.assert_rw_preds_at_addresses({
'': ({num}, {num}),
'p': ({num}, {num}),
'pl': ({num}, {num}),
'plu': ({num}, {num}),
'plum': ({num}, {num}),
})
def test_add_lists_of_readers(self):
'''Tests multiple readers at nodes
'''
for address in ('p', 'pu', 'pug'):
self.set_writer(address, 0)
for i in range(1, 4):
self.add_reader(address, i)
# ROOT:
# p: Writer: 0 Readers: [1, 2, 3]
# u: Writer: 0 Readers: [1, 2, 3]
# g: Writer: 0 Readers: [1, 2, 3]
self.assert_rwc_at_addresses({
'': ([], None, {'p'}),
'p': ([1, 2, 3], 0, {'u'}),
'pu': ([1, 2, 3], 0, {'g'}),
'pug': ([1, 2, 3], 0, {}),
})
self.assert_no_nodes_at_addresses('pugs')
self.assert_rw_count(9, 3)
self.assert_rw_preds_at_addresses({
'': ({0}, {0, 1, 2, 3}),
'p': ({0}, {0, 1, 2, 3}),
'pu': ({0}, {0, 1, 2, 3}),
'pug': ({0}, {0, 1, 2, 3}),
'pugs': ({0}, {0, 1, 2, 3}),
})
# add a writer and verify that downstream readers are gone
self.set_writer('pu', 4)
# ROOT:
# p: Writer: 0 Readers: [1, 2, 3]
# u: Writer: 4
self.assert_rwc_at_addresses({
'': ([], None, {'p'}),
'p': ([1, 2, 3], 0, {'u'}),
'pu': ([], 4, {}),
})
self.assert_no_nodes_at_addresses('pug', 'pugs')
self.assert_rw_count(3, 2)
self.assert_rw_preds_at_addresses({
'': ({0, 4}, {0, 1, 2, 3, 4}),
'p': ({0, 4}, {0, 1, 2, 3, 4}),
'pu': ({4}, {1, 2, 3, 4}),
})
def test_long_addresses(self):
"""Tests predecessor tree with len-64 addresses and token size 2
"""
self.tree = PredecessorTree(token_size=2)
address_a = \
'ca978112ca1bbdcafac231b39a23dc4da786eff8147c4e72b9807785afee48bb'
address_b = \
'3e23e8160039594a33894f6564e1b1348bbd7a0088d42c4acb73eeaed59c009d'
self.add_readers({address_a: 'txn1', address_b: 'txn2'})
self.assert_rwc_at_addresses({
address_a: (['txn1'], None, {}),
address_b: (['txn2'], None, {})
})
# Set a writer for address_a.
self.set_writer(address_a, 'txn1')
# Verify address_a now contains txn1 as the writer, with no
# readers set.
# Verify address_b didn't change when address_a was modified.
self.assert_rwc_at_addresses({
address_a: ([], 'txn1', {}),
address_b: (['txn2'], None, {})
})
# Set a writer for a prefix of address_b.
address_c = address_b[0:4]
self.set_writer(address_c, 'txn3')
# Verify address_c now contains txn3 as the writer, with
# no readers set and no children.
# Verify address_a didn't change when address_c was modified.
self.assert_rwc_at_addresses({
address_a: ([], 'txn1', {}),
address_c: ([], 'txn3', {})
})
# Verify address_b now returns None
self.assert_no_nodes_at_addresses(address_b)
# Add readers for address_a, address_b
self.add_readers({address_a: 'txn1', address_b: 'txn2'})
# Verify address_c now contains txn3 as the writer, with
# no readers set and 'e8' as a child.
self.assert_rwc_at_addresses({
address_a: (['txn1'], 'txn1', {}),
address_b: (['txn2'], None, {}),
address_c: ([], 'txn3', ['e8'])
})
self.assert_rw_preds_at_addresses({
address_a: ({'txn1'}, {'txn1'}),
address_b: ({'txn3'}, {'txn3', 'txn2'}),
address_c: ({'txn3'}, {'txn3', 'txn2'}),
})
self.assert_rw_count(2, 2)
# assertions
def assert_rwc_at_addresses(self, expected_dict):
'''
Asserts the readers, writer, and children at an address
expected_dict = {address: (readers, writer, children)}
'''
self.show_tree()
for address, rwc in expected_dict.items():
error_msg = 'Address "{}": '.format(address) + 'incorrect {}'
readers, writer, children = rwc
node = self.get_node(address)
self.assertIsNotNone(node)
self.assertEqual(readers, node.readers,
error_msg.format('readers'))
self.assertEqual(writer, node.writer, error_msg.format('writer'))
self.assertEqual(set(children), set(node.children.keys()),
error_msg.format('children'))
def assert_no_nodes_at_addresses(self, *addresses):
for address in addresses:
node = self.get_node(address)
self.assertIsNone(node,
'Address "{}": unexpected node'.format(address))
def assert_rw_count(self, reader_count, writer_count):
'''
Asserts the total number of readers and writers in the tree
'''
def count_readers(node=None):
if node is None:
node = self.get_node('') # root node
count = len(node.readers)
for child in node.children:
next_node = node.children[child]
count += count_readers(next_node)
return count
def count_writers(node=None):
if node is None:
node = self.get_node('') # root node
count = 1 if node.writer is not None else 0
for child in node.children:
next_node = node.children[child]
count += count_writers(next_node)
return count
error_msg = 'Incorrect {} count'
self.assertEqual(reader_count, count_readers(),
error_msg.format('reader'))
self.assertEqual(writer_count, count_writers(),
error_msg.format('writer'))
def assert_rw_preds_at_addresses(self, rw_pred_dict):
'''
Asserts the read predecessors and write predecessors at an address
rw_pred_dict = {address: (read_preds, write_preds)}
'''
for address, rw_preds in rw_pred_dict.items():
error_msg = 'Address "{}": '.format(
address) + 'incorrect {} predecesors'
read_preds, write_preds = rw_preds
self.assertEqual(self.tree.find_read_predecessors(address),
set(read_preds), error_msg.format('read'))
self.assertEqual(self.tree.find_write_predecessors(address),
set(write_preds), error_msg.format('write'))
# basic tree operations (for convenience)
def add_readers(self, reader_dict):
'''
reader_dict = {address: reader}
'''
for address, reader in reader_dict.items():
self.add_reader(address, reader)
def set_writers(self, writer_dict):
'''
writer_dict = {address: writer}
The order in which writers are added matters, since they can
overwrite each other. If a specific order is required,
an OrderedDict should be used.
'''
for address, writer in writer_dict.items():
self.set_writer(address, writer)
def add_reader(self, address, txn):
self.tree.add_reader(address, txn)
def set_writer(self, address, txn):
self.tree.set_writer(address, txn)
def get_node(self, address):
return self.tree.get(address)
# display
def show_tree(self):
output = tree_to_string(self.tree).split('\n')
for line in output:
LOGGER.debug(line)
def test_predecessor_tree(self):
"""Tests basic functionality of the scheduler's radix tree.
"""
address_a = \
'ca978112ca1bbdcafac231b39a23dc4da786eff8147c4e72b9807785afee48bb'
address_b = \
'3e23e8160039594a33894f6564e1b1348bbd7a0088d42c4acb73eeaed59c009d'
tree = PredecessorTree()
tree.add_reader(address_a, 'txn1')
tree.add_reader(address_b, 'txn2')
node = tree.get(address_a)
self.assertIsNotNone(node)
self.assertEqual(node.readers, ['txn1'])
self.assertIsNone(node.writer)
self.assertEqual(node.children, {})
node = tree.get(address_b)
self.assertIsNotNone(node)
self.assertEqual(node.readers, ['txn2'])
self.assertIsNone(node.writer, None)
self.assertEqual(node.children, {})
# Set a writer for address_a.
tree.set_writer(address_a, 'txn1')
# Verify address_a now contains txn1 as the writer, with no
# readers set.
node = tree.get(address_a)
self.assertIsNotNone(node)
self.assertEqual(node.readers, [])
self.assertEqual(node.writer, 'txn1')
self.assertEqual(node.children, {})
# Verify address_b didn't change when address_a was modified.
node = tree.get(address_b)
self.assertIsNotNone(node)
self.assertEqual(node.readers, ['txn2'])
self.assertIsNone(node.writer)
self.assertEqual(node.children, {})
# Set a writer for a prefix of address_b.
tree.set_writer(address_b[0:4], 'txn3')
# Verify address_b[0:4] now contains txn3 as the writer, with
# no readers set and no children.
node = tree.get(address_b[0:4])
self.assertIsNotNone(node)
self.assertEqual(node.readers, [])
self.assertEqual(node.writer, 'txn3')
self.assertEqual(node.children, {})
# Verify address_b now returns None
node = tree.get(address_b)
self.assertIsNone(node)
# Verify address_a didn't change when address_b[0:4] was modified.
node = tree.get(address_a)
self.assertIsNotNone(node)
self.assertEqual(node.readers, [])
self.assertEqual(node.writer, 'txn1')
self.assertEqual(node.children, {})
# Add readers for address_a, address_b
tree.add_reader(address_a, 'txn1')
tree.add_reader(address_b, 'txn2')
node = tree.get(address_a)
self.assertIsNotNone(node)
self.assertEqual(node.readers, ['txn1'])
self.assertEqual(node.writer, 'txn1')
self.assertEqual(node.children, {})
node = tree.get(address_b)
self.assertIsNotNone(node)
self.assertEqual(node.readers, ['txn2'])
self.assertIsNone(node.writer)
self.assertEqual(node.children, {})
# Verify address_b[0:4] now contains txn3 as the writer, with
# no readers set and 'e8' as a child.
node = tree.get(address_b[0:4])
self.assertIsNotNone(node)
self.assertEqual(node.readers, [])
self.assertEqual(node.writer, 'txn3')
self.assertEqual(list(node.children.keys()), ['e8'])
self.assertEqual(
tree.find_write_predecessors(address_a),
set(['txn1']))
self.assertEqual(
tree.find_read_predecessors(address_a),
set(['txn1']))
self.assertEqual(
tree.find_write_predecessors(address_b),
set(['txn3', 'txn2']))
self.assertEqual(
tree.find_read_predecessors(address_b),
set(['txn3']))
def setUp(self):
self.tree = PredecessorTree()
def test_long_addresses(self):
"""Tests predecessor tree with len-64 addresses and token size 2
"""
self.tree = PredecessorTree(token_size=2)
address_a = \
'ca978112ca1bbdcafac231b39a23dc4da786eff8147c4e72b9807785afee48bb'
address_b = \
'3e23e8160039594a33894f6564e1b1348bbd7a0088d42c4acb73eeaed59c009d'
self.add_readers({
address_a: 'txn1',
address_b: 'txn2'
})
self.assert_rwc_at_addresses({
address_a: (['txn1'], None, {}),
address_b: (['txn2'], None, {})
})
# Set a writer for address_a.
self.set_writer(address_a, 'txn1')
# Verify address_a now contains txn1 as the writer, with no
# readers set.
# Verify address_b didn't change when address_a was modified.
self.assert_rwc_at_addresses({
address_a: ([], 'txn1', {}),
address_b: (['txn2'], None, {})
})
# Set a writer for a prefix of address_b.
address_c = address_b[0:4]
self.set_writer(address_c, 'txn3')
# Verify address_c now contains txn3 as the writer, with
# no readers set and no children.
# Verify address_a didn't change when address_c was modified.
self.assert_rwc_at_addresses({
address_a: ([], 'txn1', {}),
address_c: ([], 'txn3', {})
})
# Verify address_b now returns None
self.assert_no_nodes_at_addresses(address_b)
# Add readers for address_a, address_b
self.add_readers({
address_a: 'txn1',
address_b: 'txn2'
})
# Verify address_c now contains txn3 as the writer, with
# no readers set and 'e8' as a child.
self.assert_rwc_at_addresses({
address_a: (['txn1'], 'txn1', {}),
address_b: (['txn2'], None, {}),
address_c: ([], 'txn3', ['e8'])
})
self.assert_rw_preds_at_addresses({
address_a: ({'txn1'}, {'txn1'}),
address_b: ({'txn3'}, {'txn3', 'txn2'}),
address_c: ({'txn3'}, {'txn3', 'txn2'}),
})
self.assert_rw_count(2, 2)
def setUp(self):
self.tree = PredecessorTree(token_size=1)
class TestPredecessorTree(unittest.TestCase):
'''
With an empty tree initialized in setUp, the predecessor tree
tests generally follow this pattern (repeated several times):
1) Add some readers or writers. In most cases, a diagram
will be given in comments to show what the tree should
look like after the additions.
2) Assert the readers, writers, and children at all addresses
in the tree (using assert_rwc_at_addresses). Possibly also
assert (using assert_no_nodes_at_addresses) that nodes don't
exist at certain addresses (this is normally done after
setting a writer).
3) Assert the total count of readers and writers in the tree
(using assert_rw_count). This ensures that nothing is in the
tree that shouldn't be there.
4) Assert the read and write predecessors for various addresses
(using assert_rw_preds_at_addresses).
Although the default token size for the predecessor tree is 2,
1 is used for most tests because it makes for more natural examples.
'''
def setUp(self):
self.tree = PredecessorTree(token_size=1)
def tearDown(self):
self.tree = None
def test_predecessor_tree(self):
'''Tests basic predecessor tree functions
This test is intended to show the evolution of a tree
over the course of normal use. Apart from testing, it
can also be used as a reference example.
Readers and writers are added in the following steps:
1) Add some readers.
2) Add readers at addresses that are initial segments
of existing node addresses.
3) Add a writer in the middle of the tree.
4) Add readers to existing nodes.
5) Add a writer to a new node.
6) Add writers in the middle of the tree.
7) Add readers to upper nodes.
8) Add readers to nodes with writers.
9) Add readers to new top nodes.
10) Add writer to top node.
11) Add readers to upper nodes, then add writers.
12) Add writer to top node, then add reader.
13) Add writer to root
'''
# 1) Add some readers.
self.add_readers({
'radix': 1,
'radish': 2,
'radon': 3,
'razzle': 4,
'rustic': 5
})
# ROOT:
# r:
# a:
# d:
# o:
# n: Readers: [3]
# i:
# x: Readers: [1]
# s:
# h: Readers: [2]
# z:
# z:
# l:
# e: Readers: [4]
# u:
# s:
# t:
# i:
# c: Readers: [5]
self.assert_rwc_at_addresses({
'r': ([], None, {'a', 'u'}),
'ra': ([], None, {'z', 'd'}),
'rad': ([], None, {'o', 'i'}),
'radi': ([], None, {'s', 'x'}),
'radix': ([1], None, {}),
'radish': ([2], None, {}),
'radon': ([3], None, {}),
'razzle': ([4], None, {}),
'ru': ([], None, {'s'}),
'rust': ([], None, {'i'}),
'rustic': ([5], None, {}),
})
self.assert_rw_count(5, 0)
self.assert_rw_preds_at_addresses({
'r': ({}, {1, 2, 3, 4, 5}),
'rad': ({}, {1, 2, 3}),
'radi': ({}, {1, 2}),
'radix': ({}, {1}),
})
# 2) Add readers at addresses that are initial segments
# of existing node addresses.
self.add_readers({
'rad': 6,
'rust': 7
})
# ROOT:
# r:
# a:
# d: Readers: [6]
# o:
# n: Readers: [3]
# i:
# x: Readers: [1]
# s:
# h: Readers: [2]
# z:
# z:
# l:
# e: Readers: [4]
# u:
# s:
# t: Readers: [7]
# i:
# c: Readers: [5]
self.assert_rwc_at_addresses({
'r': ([], None, {'a', 'u'}),
'ra': ([], None, {'z', 'd'}),
'rad': ([6], None, {'o', 'i'}),
'radi': ([], None, {'s', 'x'}),
'radix': ([1], None, {}),
'radish': ([2], None, {}),
'radon': ([3], None, {}),
'razzle': ([4], None, {}),
'ru': ([], None, {'s'}),
'rust': ([7], None, {'i'}),
'rustic': ([5], None, {}),
})
self.assert_rw_count(7, 0)
self.assert_rw_preds_at_addresses({
'ra': ({}, {1, 2, 3, 4, 6}),
'ru': ({}, {5, 7}),
})
# 3) Add a writer in the middle of the tree.
self.set_writer('radi', 8)
# ROOT:
# r:
# u:
# s:
# t: Readers: [7]
# i:
# c: Readers: [5]
# a:
# d: Readers: [6]
# o:
# n: Readers: [3]
# i: Writer: 8
# z:
# z:
# l:
# e: Readers: [4]
self.assert_no_nodes_at_addresses(
'radix',
'radish'
)
self.assert_rwc_at_addresses({
'r': ([], None, {'a', 'u'}),
'ra': ([], None, {'z', 'd'}),
'rad': ([6], None, {'o', 'i'}),
'radi': ([], 8, {}),
'radon': ([3], None, {}),
'razzle': ([4], None, {}),
'ru': ([], None, {'s'}),
'rust': ([7], None, {'i'}),
'rustic': ([5], None, {}),
})
self.assert_rw_count(5, 1)
self.assert_rw_preds_at_addresses({
'rad': ({8}, {3, 6, 8}),
'radi': ({8}, {6, 8}),
'radical': ({8}, {6, 8}),
})
# 4) Add readers to existing nodes.
self.add_readers({
'rad': 9,
'radi': 10,
'radio': 11,
'radon': 12,
'rust': 13
})
# ROOT:
# r:
# u:
# s:
# t: Readers: [7, 13]
# i:
# c: Readers: [5]
# a:
# d: Readers: [6, 9]
# o:
# n: Readers: [3, 12]
# i: Writer: 8 Readers: [10]
# o: Readers: [11]
# z:
# z:
# l:
# e: Readers: [4]
self.assert_rwc_at_addresses({
'r': ([], None, {'a', 'u'}),
'ra': ([], None, {'z', 'd'}),
'rad': ([6, 9], None, {'o', 'i'}),
'radi': ([10], 8, {'o'}),
'radio': ([11], None, {}),
'radon': ([3, 12], None, {}),
'razzle': ([4], None, {}),
'ru': ([], None, {'s'}),
'rust': ([7, 13], None, {'i'}),
'rustic': ([5], None, {}),
})
self.assert_rw_count(10, 1)
self.assert_rw_preds_at_addresses({
'rad': ({8}, {6, 9, 10, 8, 11, 3, 12}),
'ru': ({}, {7, 13, 5}),
})
# 5) Add a writer to a new node.
self.set_writer('radii', 14)
# ROOT:
# r:
# u:
# s:
# t: Readers: [7, 13]
# i:
# c: Readers: [5]
# a:
# d: Readers: [6, 9]
# o:
# n: Readers: [3, 12]
# i: Writer: 8 Readers: [10]
# o: Readers: [11]
# i: Writer: 14
# z:
# z:
# l:
# e: Readers: [4]
self.assert_rwc_at_addresses({
'r': ([], None, {'a', 'u'}),
'ra': ([], None, {'z', 'd'}),
'rad': ([6, 9], None, {'o', 'i'}),
'radi': ([10], 8, {'o', 'i'}),
'radii': ([], 14, {}),
'radio': ([11], None, {}),
'radon': ([3, 12], None, {}),
'razzle': ([4], None, {}),
'ru': ([], None, {'s'}),
'rust': ([7, 13], None, {'i'}),
'rustic': ([5], None, {}),
})
self.assert_rw_count(10, 2)
self.assert_rw_preds_at_addresses({
'radi': ({8, 14}, {6, 9, 10, 8, 14, 11}),
'radii': ({14}, {6, 9, 10, 14}),
'radio': ({8}, {6, 9, 10, 8, 11}),
})
# 6) Add writers in the middle of the tree.
self.set_writers({
'rust': 15,
'rad': 16
})
# ROOT:
# r:
# u:
# s:
# t: Writer: 15
# a:
# d: Writer: 16
# z:
# z:
# l:
# e: Readers: [4]
self.assert_no_nodes_at_addresses(
'radi',
'radii',
'radio',
'radon',
'rustic'
)
self.assert_rwc_at_addresses({
'r': ([], None, {'a', 'u'}),
'ra': ([], None, {'z', 'd'}),
'rad': ([], 16, {}),
'razzle': ([4], None, {}),
'ru': ([], None, {'s'}),
'rust': ([], 15, {}),
})
self.assert_rw_count(1, 2)
self.assert_rw_preds_at_addresses({
'r': ({16, 15}, {16, 4, 15}),
'ru': ({15}, {15}),
'rust': ({15}, {15}),
'rustic': ({15}, {15}),
})
# 7) Add readers to upper nodes.
self.add_readers({
'r': 17,
'ra': 18,
'ru': 19,
})
# ROOT:
# r: Readers: [17]
# u: Readers: [19]
# s:
# t: Writer: 15
# a: Readers: [18]
# d: Writer: 16
# z:
# z:
# l:
# e: Readers: [4]
self.assert_rwc_at_addresses({
'r': ([17], None, {'a', 'u'}),
'ra': ([18], None, {'z', 'd'}),
'rad': ([], 16, {}),
'razzle': ([4], None, {}),
'ru': ([19], None, {'s'}),
'rust': ([], 15, {}),
})
self.assert_rw_count(4, 2)
self.assert_rw_preds_at_addresses({
'r': ({15, 16}, {17, 19, 15, 18, 16, 4}),
'ru': ({15}, {17, 19, 15}),
})
# 8) Add readers to nodes with writers.
self.add_readers({
'rad': 20,
'rust': 21
})
# ROOT:
# r: Readers: [17]
# u: Readers: [19]
# s:
# t: Writer: 15 Readers: [21]
# a: Readers: [18]
# d: Writer: 16 Readers: [20]
# z:
# z:
# l:
# e: Readers: [4]
self.assert_rwc_at_addresses({
'': ([], None, {'r'}),
'r': ([17], None, {'a', 'u'}),
'ra': ([18], None, {'z', 'd'}),
'rad': ([20], 16, {}),
'razzle': ([4], None, {}),
'ru': ([19], None, {'s'}),
'rust': ([21], 15, {}),
})
self.assert_rw_count(6, 2)
self.assert_rw_preds_at_addresses({
'': ({16, 15}, {17, 18, 20, 16, 4, 19, 21, 15}),
'rad': ({16}, {17, 18, 20, 16}),
'rust': ({15}, {17, 19, 21, 15}),
})
# 9) Add readers to new top nodes.
self.add_readers({
's': 22,
't': 23,
})
# ROOT:
# t: Readers: [23]
# s: Readers: [22]
# r: Readers: [17]
# u: Readers: [19]
# s:
# t: Writer: 15 Readers: [21]
# a: Readers: [18]
# d: Writer: 16 Readers: [20]
# z:
# z:
# l:
# e: Readers: [4]
self.assert_rwc_at_addresses({
'': ([], None, {'r', 's', 't'}),
'r': ([17], None, {'a', 'u'}),
'ra': ([18], None, {'z', 'd'}),
'rad': ([20], 16, {}),
'razzle': ([4], None, {}),
'ru': ([19], None, {'s'}),
'rust': ([21], 15, {}),
's': ([22], None, {}),
't': ([23], None, {}),
})
self.assert_rw_count(8, 2)
self.assert_rw_preds_at_addresses({
's': ({}, {22}),
't': ({}, {23}),
'r': ({16, 15}, {17, 18, 20, 16, 4, 19, 21, 15}),
})
# 10) Add writer to top node.
self.set_writer('s', 24)
# ROOT:
# t: Readers: [23]
# s: Writer: 24
# r: Readers: [17]
# u: Readers: [19]
# s:
# t: Writer: 15 Readers: [21]
# a: Readers: [18]
# d: Writer: 16 Readers: [20]
# z:
# z:
# l:
# e: Readers: [4]
self.assert_rwc_at_addresses({
'r': ([17], None, {'a', 'u'}),
'ra': ([18], None, {'z', 'd'}),
'rad': ([20], 16, {}),
'razzle': ([4], None, {}),
'ru': ([19], None, {'s'}),
'rust': ([21], 15, {}),
's': ([], 24, {}),
't': ([23], None, {}),
})
self.assert_rw_count(7, 3)
self.assert_rw_preds_at_addresses({
's': ({24}, {24}),
't': ({}, {23}),
'r': ({16, 15}, {17, 18, 20, 16, 4, 19, 21, 15}),
})
# 11) Add readers to upper nodes, then add writers.
self.add_readers({
'ra': 25,
'ru': 26,
})
self.set_writers({
'ra': 27,
'ru': 28,
})
# ROOT:
# t: Readers: [23]
# s: Writer: 24
# r: Readers: [17]
# u: Writer: 28
# a: Writer: 27
self.assert_rwc_at_addresses({
'r': ([17], None, {'a', 'u'}),
'ra': ([], 27, {}),
'ru': ([], 28, {}),
's': ([], 24, {}),
't': ([23], None, {}),
})
self.assert_no_nodes_at_addresses(
'rad',
'razzle',
'rust',
)
self.assert_rw_preds_at_addresses({
'r': ({27, 28}, {17, 27, 28}),
'ra': ({27}, {17, 27}),
'rad': ({27}, {17, 27}),
})
# 12) Add writer to top node, then add reader.
self.set_writer('r', 29)
self.add_reader('r', 30)
# ROOT:
# t: Readers: [23]
# s: Writer: 24
# r: Writer: 29 Readers: [30]
self.assert_rwc_at_addresses({
'': ([], None, {'r', 's', 't'}),
'r': ([30], 29, {}),
's': ([], 24, {}),
't': ([23], None, {}),
})
self.assert_no_nodes_at_addresses(
'ra',
'ru',
)
self.assert_rw_count(2, 2)
self.assert_rw_preds_at_addresses({
'r': ({29}, {30, 29}),
'roger': ({29}, {30, 29}),
'ebert': ({}, {}),
})
# 13) Add writer to root
self.set_writer('', 0)
# ROOT: Writer: 0
self.assert_rwc_at_addresses({
'': ([], 0, {})
})
self.assert_no_nodes_at_addresses(
'r',
's',
't'
)
self.assert_rw_count(0, 1)
self.assert_rw_preds_at_addresses({
'': ({0}, {0}),
'r': ({0}, {0}),
's': ({0}, {0}),
'rabbit': ({0}, {0}),
})
def test_initial_segment_addresses(self):
'''Tests addresses with and without common initial segments
'''
expected = (
('c', 1),
('ca', 2),
('cat', 3),
)
for address, val in expected:
self.set_writer(address, val)
self.add_reader(address, val)
# ROOT:
# c: Writer: 1 Readers: [1]
# a: Writer: 2 Readers: [2]
# t: Writer: 3 Readers: [3]
self.assert_rwc_at_addresses({
'': ([], None, {'c'}),
'c': ([1], 1, {'a'}),
'ca': ([2], 2, {'t'}),
'cat': ([3], 3, {}),
})
self.assert_rw_count(3, 3)
# 'cath' isn't on the tree, so it should have
# the same predecessors as 'cat'
self.assert_rw_preds_at_addresses({
'': ({1, 2, 3}, {1, 2, 3}),
'c': ({1, 2, 3}, {1, 2, 3}),
'ca': ({2, 3}, {1, 2, 3}),
'cat': ({3}, {1, 2, 3}),
'cath': ({3}, {1, 2, 3}),
})
# add reader and writer at an address with a common initial segment
self.set_writer('carp', 4)
self.add_reader('carp', 4)
# ROOT:
# c: Writer: 1 Readers: [1]
# a: Writer: 2 Readers: [2]
# r:
# p: Writer: 4 Readers: [4]
# t: Writer: 3 Readers: [3]
self.assert_rwc_at_addresses({
'': ([], None, {'c'}),
'c': ([1], 1, {'a'}),
'ca': ([2], 2, {'t', 'r'}),
'cat': ([3], 3, {}),
'carp': ([4], 4, {}),
})
self.assert_rw_count(4, 4)
self.assert_rw_preds_at_addresses({
'': ({1, 2, 3, 4}, {1, 2, 3, 4}),
'c': ({1, 2, 3, 4}, {1, 2, 3, 4}),
'ca': ({2, 3, 4}, {1, 2, 3, 4}),
'cat': ({3}, {1, 2, 3}),
'cath': ({3}, {1, 2, 3}),
'carp': ({4}, {1, 2, 4}),
})
# add reader and writer at an address with no common initial segment
self.set_writer('dog', 5)
self.add_reader('dog', 5)
# ROOT:
# c: Writer: 1 Readers: [1]
# a: Writer: 2 Readers: [2]
# r:
# p: Writer: 4 Readers: [4]
# t: Writer: 3 Readers: [3]
# d:
# o:
# g: Writer: 5 Readers: [5]
self.assert_rwc_at_addresses({
'': ([], None, {'c', 'd'}),
'c': ([1], 1, {'a'}),
'ca': ([2], 2, {'t', 'r'}),
'cat': ([3], 3, {}),
'carp': ([4], 4, {}),
'dog': ([5], 5, {}),
})
self.assert_rw_count(5, 5)
self.assert_rw_preds_at_addresses({
'': ({1, 2, 3, 4, 5}, {1, 2, 3, 4, 5}),
'c': ({1, 2, 3, 4}, {1, 2, 3, 4}),
'ca': ({2, 3, 4}, {1, 2, 3, 4}),
'cat': ({3}, {1, 2, 3}),
'cath': ({3}, {1, 2, 3}),
'carp': ({4}, {1, 2, 4}),
'dog': ({5}, {5}),
})
# check predecessors of an address that isn't on the tree at all
self.assert_rw_preds_at_addresses({
'yak': ({}, {}),
})
# add readers to root and check again
self.add_reader('', 6)
self.add_reader('', 7)
# ROOT: Readers: [6, 7]
# c: Writer: 1 Readers: [1]
# a: Writer: 2 Readers: [2]
# r:
# p: Writer: 4 Readers: [4]
# t: Writer: 3 Readers: [3]
# d:
# o:
# g: Writer: 5 Readers: [5]
self.assert_rwc_at_addresses({
'': ([6, 7], None, {'c', 'd'}),
'c': ([1], 1, {'a'}),
'ca': ([2], 2, {'t', 'r'}),
'cat': ([3], 3, {}),
'carp': ([4], 4, {}),
'dog': ([5], 5, {}),
})
self.assert_rw_count(7, 5)
self.assert_rw_preds_at_addresses({
'': ({1, 2, 3, 4, 5}, {1, 2, 3, 4, 5, 6, 7}),
'c': ({1, 2, 3, 4}, {1, 2, 3, 4, 6, 7}),
'ca': ({2, 3, 4}, {1, 2, 3, 4, 6, 7}),
'cat': ({3}, {1, 2, 3, 6, 7}),
'cath': ({3}, {1, 2, 3, 6, 7}),
'carp': ({4}, {1, 2, 4, 6, 7}),
'dog': ({5}, {5, 6, 7}),
'yak': ({}, {6, 7}),
})
def test_add_writers_to_same_node(self):
'''Adds a series of writers one after the other
to a single node, verifying after each new writer
that there is nothing else at that node and that
there is just one writer in the whole tree.
'''
# Set writer num at 'address'
for num in range(10):
self.set_writer('plum', num)
# ROOT:
# p:
# l:
# u:
# m: Writer: ,num
self.assert_rwc_at_addresses({
'': ([], None, {'p'}),
'p': ([], None, {'l'}),
'pl': ([], None, {'u'}),
'plu': ([], None, {'m'}),
'plum': ([], num, {}),
})
self.assert_rw_count(0, 1)
self.assert_rw_preds_at_addresses({
'': ({num}, {num}),
'p': ({num}, {num}),
'pl': ({num}, {num}),
'plu': ({num}, {num}),
'plum': ({num}, {num}),
})
def test_add_lists_of_readers(self):
'''Tests multiple readers at nodes
'''
for address in ('p', 'pu', 'pug'):
self.set_writer(address, 0)
for i in range(1, 4):
self.add_reader(address, i)
# ROOT:
# p: Writer: 0 Readers: [1, 2, 3]
# u: Writer: 0 Readers: [1, 2, 3]
# g: Writer: 0 Readers: [1, 2, 3]
self.assert_rwc_at_addresses({
'': ([], None, {'p'}),
'p': ([1, 2, 3], 0, {'u'}),
'pu': ([1, 2, 3], 0, {'g'}),
'pug': ([1, 2, 3], 0, {}),
})
self.assert_no_nodes_at_addresses('pugs')
self.assert_rw_count(9, 3)
self.assert_rw_preds_at_addresses({
'': ({0}, {0, 1, 2, 3}),
'p': ({0}, {0, 1, 2, 3}),
'pu': ({0}, {0, 1, 2, 3}),
'pug': ({0}, {0, 1, 2, 3}),
'pugs': ({0}, {0, 1, 2, 3}),
})
# add a writer and verify that downstream readers are gone
self.set_writer('pu', 4)
# ROOT:
# p: Writer: 0 Readers: [1, 2, 3]
# u: Writer: 4
self.assert_rwc_at_addresses({
'': ([], None, {'p'}),
'p': ([1, 2, 3], 0, {'u'}),
'pu': ([], 4, {}),
})
self.assert_no_nodes_at_addresses('pug', 'pugs')
self.assert_rw_count(3, 2)
self.assert_rw_preds_at_addresses({
'': ({0, 4}, {0, 1, 2, 3, 4}),
'p': ({0, 4}, {0, 1, 2, 3, 4}),
'pu': ({4}, {1, 2, 3, 4}),
})
def test_long_addresses(self):
"""Tests predecessor tree with len-64 addresses and token size 2
"""
self.tree = PredecessorTree(token_size=2)
address_a = \
'ca978112ca1bbdcafac231b39a23dc4da786eff8147c4e72b9807785afee48bb'
address_b = \
'3e23e8160039594a33894f6564e1b1348bbd7a0088d42c4acb73eeaed59c009d'
self.add_readers({
address_a: 'txn1',
address_b: 'txn2'
})
self.assert_rwc_at_addresses({
address_a: (['txn1'], None, {}),
address_b: (['txn2'], None, {})
})
# Set a writer for address_a.
self.set_writer(address_a, 'txn1')
# Verify address_a now contains txn1 as the writer, with no
# readers set.
# Verify address_b didn't change when address_a was modified.
self.assert_rwc_at_addresses({
address_a: ([], 'txn1', {}),
address_b: (['txn2'], None, {})
})
# Set a writer for a prefix of address_b.
address_c = address_b[0:4]
self.set_writer(address_c, 'txn3')
# Verify address_c now contains txn3 as the writer, with
# no readers set and no children.
# Verify address_a didn't change when address_c was modified.
self.assert_rwc_at_addresses({
address_a: ([], 'txn1', {}),
address_c: ([], 'txn3', {})
})
# Verify address_b now returns None
self.assert_no_nodes_at_addresses(address_b)
# Add readers for address_a, address_b
self.add_readers({
address_a: 'txn1',
address_b: 'txn2'
})
# Verify address_c now contains txn3 as the writer, with
# no readers set and 'e8' as a child.
self.assert_rwc_at_addresses({
address_a: (['txn1'], 'txn1', {}),
address_b: (['txn2'], None, {}),
address_c: ([], 'txn3', ['e8'])
})
self.assert_rw_preds_at_addresses({
address_a: ({'txn1'}, {'txn1'}),
address_b: ({'txn3'}, {'txn3', 'txn2'}),
address_c: ({'txn3'}, {'txn3', 'txn2'}),
})
self.assert_rw_count(2, 2)
# assertions
def assert_rwc_at_addresses(self, expected_dict):
'''
Asserts the readers, writer, and children at an address
expected_dict = {address: (readers, writer, children)}
'''
self.show_tree()
for address, rwc in expected_dict.items():
error_msg = 'Address "{}": '.format(address) + 'incorrect {}'
readers, writer, children = rwc
node = self.get_node(address)
self.assertIsNotNone(node)
self.assertEqual(
readers,
node.readers,
error_msg.format('readers'))
self.assertEqual(
writer,
node.writer,
error_msg.format('writer'))
self.assertEqual(
set(children),
set(node.children.keys()),
error_msg.format('children'))
def assert_no_nodes_at_addresses(self, *addresses):
for address in addresses:
node = self.get_node(address)
self.assertIsNone(
node,
'Address "{}": unexpected node'.format(address))
def assert_rw_count(self, reader_count, writer_count):
'''
Asserts the total number of readers and writers in the tree
'''
def count_readers(node=None):
if node is None:
node = self.get_node('') # root node
count = len(node.readers)
for child in node.children:
next_node = node.children[child]
count += count_readers(next_node)
return count
def count_writers(node=None):
if node is None:
node = self.get_node('') # root node
count = 1 if node.writer is not None else 0
for child in node.children:
next_node = node.children[child]
count += count_writers(next_node)
return count
error_msg = 'Incorrect {} count'
self.assertEqual(
reader_count,
count_readers(),
error_msg.format('reader'))
self.assertEqual(
writer_count,
count_writers(),
error_msg.format('writer'))
def assert_rw_preds_at_addresses(self, rw_pred_dict):
'''
Asserts the read predecessors and write predecessors at an address
rw_pred_dict = {address: (read_preds, write_preds)}
'''
for address, rw_preds in rw_pred_dict.items():
error_msg = 'Address "{}": '.format(
address) + 'incorrect {} predecesors'
read_preds, write_preds = rw_preds
self.assertEqual(
self.tree.find_read_predecessors(address),
set(read_preds),
error_msg.format('read'))
self.assertEqual(
self.tree.find_write_predecessors(address),
set(write_preds),
error_msg.format('write'))
# basic tree operations (for convenience)
def add_readers(self, reader_dict):
'''
reader_dict = {address: reader}
'''
for address, reader in reader_dict.items():
self.add_reader(address, reader)
def set_writers(self, writer_dict):
'''
writer_dict = {address: writer}
The order in which writers are added matters, since they can
overwrite each other. If a specific order is required,
an OrderedDict should be used.
'''
for address, writer in writer_dict.items():
self.set_writer(address, writer)
def add_reader(self, address, txn):
self.tree.add_reader(address, txn)
def set_writer(self, address, txn):
self.tree.set_writer(address, txn)
def get_node(self, address):
return self.tree.get(address)
# display
def show_tree(self):
output = tree_to_string(self.tree).split('\n')
for line in output:
LOGGER.debug(line)
