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 testpeek(self):

        d = util.lrucachedict(4)

        d['a'] = 'va'

        d['b'] = 'vb'

        d['c'] = 'vc'

        with self.assertRaises(KeyError):

            d.peek('missing')

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

        self.assertIsNone(d.peek('missing', None))

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

        self.assertEqual(d.peek('a'), 'va')

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

    def testpop(self):

        d = util.lrucachedict(4)

        d['a'] = 'va'

        d['b'] = 'vb'

        d['c'] = 'vc'

        with self.assertRaises(KeyError):

            d.pop('missing')

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

        self.assertIsNone(d.pop('missing', None))

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

        self.assertEqual(d.pop('b'), 'vb')

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

    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)