view tests/test-lrucachedict.py @ 40527:1b49b84d5ed5

pycompat: adding Linux detection and fixing Mac

Python 3 recommends detecting OSs with the prefix of the platform, but we were
comparing the full string for macOS. We also didn't have Linux detection, which
is convenient for extensions to use (rather than have some OSs detected by hg
and some by the extension).

Reference:
https://docs.python.org/3/library/sys.html#sys.platform

Differential Revision: https://phab.mercurial-scm.org/D5227

from __future__ import absolute_import, print_function

import unittest

import silenttestrunner

from mercurial import (
    util,
)

class testlrucachedict(unittest.TestCase):
    def testsimple(self):
        d = util.lrucachedict(4)
        self.assertEqual(d.capacity, 4)
        d.insert('a', 'va', cost=2)
        d['b'] = 'vb'
        d['c'] = 'vc'
        d.insert('d', 'vd', cost=42)

        self.assertEqual(d['a'], 'va')
        self.assertEqual(d['b'], 'vb')
        self.assertEqual(d['c'], 'vc')
        self.assertEqual(d['d'], 'vd')

        self.assertEqual(d.totalcost, 44)

        # 'a' should be dropped because it was least recently used.
        d['e'] = 've'
        self.assertNotIn('a', d)
        self.assertIsNone(d.get('a'))
        self.assertEqual(d.totalcost, 42)

        self.assertEqual(d['b'], 'vb')
        self.assertEqual(d['c'], 'vc')
        self.assertEqual(d['d'], 'vd')
        self.assertEqual(d['e'], 've')

        # Replacing item with different cost adjusts totalcost.
        d.insert('e', 've', cost=4)
        self.assertEqual(d.totalcost, 46)

        # Touch entries in some order (both get and set).
        d['e']
        d['c'] = 'vc2'
        d['d']
        d['b'] = 'vb2'

        # 'e' should be dropped now
        d['f'] = 'vf'
        self.assertNotIn('e', d)
        self.assertEqual(d['b'], 'vb2')
        self.assertEqual(d['c'], 'vc2')
        self.assertEqual(d['d'], 'vd')
        self.assertEqual(d['f'], 'vf')

        d.clear()
        for key in ('a', 'b', 'c', 'd', 'e', 'f'):
            self.assertNotIn(key, d)

    def testunfull(self):
        d = util.lrucachedict(4)
        d['a'] = 1
        d['b'] = 2
        d['a']
        d['b']

        for key in ('a', 'b'):
            self.assertIn(key, d)

    def testget(self):
        d = util.lrucachedict(4)
        d['a'] = 'va'
        d['b'] = 'vb'
        d['c'] = 'vc'

        self.assertIsNone(d.get('missing'))
        self.assertEqual(list(d), ['c', 'b', 'a'])

        self.assertEqual(d.get('a'), 'va')
        self.assertEqual(list(d), ['a', 'c', 'b'])

    def testcopypartial(self):
        d = util.lrucachedict(4)
        d.insert('a', 'va', cost=4)
        d.insert('b', 'vb', cost=2)

        dc = d.copy()

        self.assertEqual(len(dc), 2)
        self.assertEqual(dc.totalcost, 6)
        for key in ('a', 'b'):
            self.assertIn(key, dc)
            self.assertEqual(dc[key], 'v%s' % key)

        self.assertEqual(len(d), 2)
        for key in ('a', 'b'):
            self.assertIn(key, d)
            self.assertEqual(d[key], 'v%s' % key)

        d['c'] = 'vc'
        del d['b']
        self.assertEqual(d.totalcost, 4)
        dc = d.copy()
        self.assertEqual(len(dc), 2)
        self.assertEqual(dc.totalcost, 4)
        for key in ('a', 'c'):
            self.assertIn(key, dc)
            self.assertEqual(dc[key], 'v%s' % key)

    def testcopyempty(self):
        d = util.lrucachedict(4)
        dc = d.copy()
        self.assertEqual(len(dc), 0)

    def testcopyfull(self):
        d = util.lrucachedict(4)
        d.insert('a', 'va', cost=42)
        d['b'] = 'vb'
        d['c'] = 'vc'
        d['d'] = 'vd'

        dc = d.copy()

        for key in ('a', 'b', 'c', 'd'):
            self.assertIn(key, dc)
            self.assertEqual(dc[key], 'v%s' % key)

        self.assertEqual(d.totalcost, 42)
        self.assertEqual(dc.totalcost, 42)

        # 'a' should be dropped because it was least recently used.
        dc['e'] = 've'
        self.assertNotIn('a', dc)
        for key in ('b', 'c', 'd', 'e'):
            self.assertIn(key, dc)
            self.assertEqual(dc[key], 'v%s' % key)

        self.assertEqual(d.totalcost, 42)
        self.assertEqual(dc.totalcost, 0)

        # Contents and order of original dict should remain unchanged.
        dc['b'] = 'vb_new'

        self.assertEqual(list(iter(d)), ['d', 'c', 'b', 'a'])
        for key in ('a', 'b', 'c', 'd'):
            self.assertEqual(d[key], 'v%s' % key)

        d = util.lrucachedict(4, maxcost=42)
        d.insert('a', 'va', cost=5)
        d.insert('b', 'vb', cost=4)
        d.insert('c', 'vc', cost=3)
        dc = d.copy()
        self.assertEqual(dc.maxcost, 42)
        self.assertEqual(len(dc), 3)

        # Max cost can be lowered as part of copy.
        dc = d.copy(maxcost=10)
        self.assertEqual(dc.maxcost, 10)
        self.assertEqual(len(dc), 2)
        self.assertEqual(dc.totalcost, 7)
        self.assertIn('b', dc)
        self.assertIn('c', dc)

    def testcopydecreasecapacity(self):
        d = util.lrucachedict(5)
        d.insert('a', 'va', cost=4)
        d.insert('b', 'vb', cost=2)
        d['c'] = 'vc'
        d['d'] = 'vd'

        dc = d.copy(2)
        self.assertEqual(dc.totalcost, 0)
        for key in ('a', 'b'):
            self.assertNotIn(key, dc)
        for key in ('c', 'd'):
            self.assertIn(key, dc)
            self.assertEqual(dc[key], 'v%s' % key)

        dc.insert('e', 've', cost=7)
        self.assertEqual(dc.totalcost, 7)
        self.assertNotIn('c', dc)
        for key in ('d', 'e'):
            self.assertIn(key, dc)
            self.assertEqual(dc[key], 'v%s' % key)

        # Original should remain unchanged.
        self.assertEqual(d.totalcost, 6)
        for key in ('a', 'b', 'c', 'd'):
            self.assertIn(key, d)
            self.assertEqual(d[key], 'v%s' % key)

    def testcopyincreasecapacity(self):
        d = util.lrucachedict(5)
        d['a'] = 'va'
        d['b'] = 'vb'
        d['c'] = 'vc'
        d['d'] = 'vd'

        dc = d.copy(6)
        for key in ('a', 'b', 'c', 'd'):
            self.assertIn(key, dc)
            self.assertEqual(dc[key], 'v%s' % key)

        dc['e'] = 've'
        dc['f'] = 'vf'
        for key in ('a', 'b', 'c', 'd', 'e', 'f'):
            self.assertIn(key, dc)
            self.assertEqual(dc[key], 'v%s' % key)

        dc['g'] = 'vg'
        self.assertNotIn('a', dc)
        for key in ('b', 'c', 'd', 'e', 'f', 'g'):
            self.assertIn(key, dc)
            self.assertEqual(dc[key], 'v%s' % key)

        # Original should remain unchanged.
        for key in ('a', 'b', 'c', 'd'):
            self.assertIn(key, d)
            self.assertEqual(d[key], 'v%s' % key)

    def testpopoldest(self):
        d = util.lrucachedict(4)
        d.insert('a', 'va', cost=10)
        d.insert('b', 'vb', cost=5)

        self.assertEqual(len(d), 2)
        self.assertEqual(d.popoldest(), ('a', 'va'))
        self.assertEqual(len(d), 1)
        self.assertEqual(d.totalcost, 5)
        self.assertEqual(d.popoldest(), ('b', 'vb'))
        self.assertEqual(len(d), 0)
        self.assertEqual(d.totalcost, 0)
        self.assertIsNone(d.popoldest())

        d['a'] = 'va'
        d['b'] = 'vb'
        d['c'] = 'vc'
        d['d'] = 'vd'

        self.assertEqual(d.popoldest(), ('a', 'va'))
        self.assertEqual(len(d), 3)
        for key in ('b', 'c', 'd'):
            self.assertEqual(d[key], 'v%s' % key)

        d['a'] = 'va'
        self.assertEqual(d.popoldest(), ('b', 'vb'))

    def testmaxcost(self):
        # Item cost is zero by default.
        d = util.lrucachedict(6, maxcost=10)
        d['a'] = 'va'
        d['b'] = 'vb'
        d['c'] = 'vc'
        d['d'] = 'vd'
        self.assertEqual(len(d), 4)
        self.assertEqual(d.totalcost, 0)

        d.clear()

        # Insertion to exact cost threshold works without eviction.
        d.insert('a', 'va', cost=6)
        d.insert('b', 'vb', cost=4)

        self.assertEqual(len(d), 2)
        self.assertEqual(d['a'], 'va')
        self.assertEqual(d['b'], 'vb')

        # Inserting a new element with 0 cost works.
        d['c'] = 'vc'
        self.assertEqual(len(d), 3)

        # Inserting a new element with cost putting us above high
        # water mark evicts oldest single item.
        d.insert('d', 'vd', cost=1)
        self.assertEqual(len(d), 3)
        self.assertEqual(d.totalcost, 5)
        self.assertNotIn('a', d)
        for key in ('b', 'c', 'd'):
            self.assertEqual(d[key], 'v%s' % key)

        # Inserting a new element with enough room for just itself
        # evicts all items before.
        d.insert('e', 've', cost=10)
        self.assertEqual(len(d), 1)
        self.assertEqual(d.totalcost, 10)
        self.assertIn('e', d)

        # Inserting a new element with cost greater than threshold
        # still retains that item.
        d.insert('f', 'vf', cost=11)
        self.assertEqual(len(d), 1)
        self.assertEqual(d.totalcost, 11)
        self.assertIn('f', d)

        # Inserting a new element will evict the last item since it is
        # too large.
        d['g'] = 'vg'
        self.assertEqual(len(d), 1)
        self.assertEqual(d.totalcost, 0)
        self.assertIn('g', d)

        d.clear()

        d.insert('a', 'va', cost=7)
        d.insert('b', 'vb', cost=3)
        self.assertEqual(len(d), 2)

        # Replacing a value with smaller cost won't result in eviction.
        d.insert('b', 'vb2', cost=2)
        self.assertEqual(len(d), 2)

        # Replacing a value with a higher cost will evict when threshold
        # exceeded.
        d.insert('b', 'vb3', cost=4)
        self.assertEqual(len(d), 1)
        self.assertNotIn('a', d)

    def testmaxcostcomplex(self):
        d = util.lrucachedict(100, maxcost=100)
        d.insert('a', 'va', cost=9)
        d.insert('b', 'vb', cost=21)
        d.insert('c', 'vc', cost=7)
        d.insert('d', 'vc', cost=50)
        self.assertEqual(d.totalcost, 87)

        # Inserting new element should free multiple elements so we hit
        # low water mark.
        d.insert('e', 'vd', cost=25)
        self.assertEqual(len(d), 2)
        self.assertNotIn('a', d)
        self.assertNotIn('b', d)
        self.assertNotIn('c', d)
        self.assertIn('d', d)
        self.assertIn('e', d)

if __name__ == '__main__':
    silenttestrunner.main(__name__)