tests/testsat.py

   1 #!/usr/bin/env python
   2 from basetest import BaseTest
   3 import sys
   4 import unittest
   5
   6 sys.path.insert(0, '..')
   7 from zeroinstall.injector import model, arch, qdom
   8 from zeroinstall.injector.namespaces import XMLNS_IFACE
   9
  10 from zeroinstall.injector.solver import SATSolver as Solver
  11 from zeroinstall.injector import sat
  12
  13 import logging
  14 logger = logging.getLogger()
  15
  16 class Stores:
  17         def lookup_maybe(self, digests):
  18                 return "/"
  19
  20 stores = Stores()
  21
  22 uri_prefix = 'http://localhost/tests/'
  23
  24 class Version:
  25         def __init__(self, n):
  26                 self.n = n
  27                 self.requires = []
  28                 self.arch = None
  29
  30         def add_requires(self, lib, min_v, max_v):
  31                 self.requires.append((lib, min_v, max_v))
  32
  33 class Program:
  34         def __init__(self, name):
  35                 self.name = name
  36                 self.versions = {}
  37
  38         def get_version(self, version):
  39                 if version not in self.versions:
  40                         self.versions[version] = Version(version)
  41                 return self.versions[version]
  42
  43         def build_feed(self):
  44                 def child(parent, name, attrs = None):
  45                         new = qdom.Element(XMLNS_IFACE, name, attrs or {})
  46                         parent.childNodes.append(new)
  47                         return new
  48
  49                 root = qdom.Element(XMLNS_IFACE, 'interface', {'uri' : uri_prefix + self.name})
  50                 child(root, 'name').content = self.name
  51                 child(root, 'summary').content = self.name
  52
  53                 i = 0
  54                 for version in self.versions.values():
  55                         attrs = {
  56                                 'id': str(i),
  57                                 'version': str(version.n),
  58                                 'main': 'dummy',
  59                         }
  60                         if version.arch:
  61                                 attrs['arch'] = version.arch
  62                         impl = child(root, 'implementation', attrs)
  63                         child(impl, 'manifest-digest', {'sha1new': '1234'})
  64                         for lib, min_v, max_v in version.requires:
  65                                 req = child(impl, 'requires', {'interface': uri_prefix + lib})
  66                                 child(req, 'version', {
  67                                         'before': str(int(max_v) + 1),
  68                                         'not-before': min_v})
  69                         i += 1
  70
  71                 feed = model.ZeroInstallFeed(root)
  72                 feed.last_modified = 1
  73                 return feed
  74
  75 class TestCache:
  76         def __init__(self):
  77                 self.progs = {}
  78                 self.interfaces = {}
  79                 self.feeds = {}
  80
  81         def get_prog(self, prog):
  82                 if not prog in self.progs:
  83                         self.progs[prog] = Program(prog)
  84                 return self.progs[prog]
  85
  86         def get_interface(self, uri):
  87                 if uri not in self.interfaces:
  88                         iface = model.Interface(uri)
  89                         self.interfaces[uri] = iface
  90                 return self.interfaces[uri]
  91
  92         def get_feed(self, url):
  93                 if url not in self.feeds:
  94                         feed = self.progs[url.rsplit('/', 1)[1]].build_feed()
  95                         self.feeds[url] = feed
  96                 return self.feeds[url]
  97
  98         def get_feed_imports(self, iface):
  99                 return []
 100
 101 def assertSelection(expected, repo):
 102         cache = TestCache()
 103
 104         expected = [tuple(e.strip().split('-')) for e in expected.split(",")]
 105
 106         for line in repo.split('\n'):
 107                 line = line.strip()
 108                 if not line: continue
 109                 if ':' in line:
 110                         prog, versions = line.split(':')
 111                         prog = prog.strip()
 112                         if ' ' in prog:
 113                                 prog, prog_arch = prog.split()
 114                         else:
 115                                 prog_arch = None
 116                         for v in versions.split():
 117                                 cache.get_prog(prog).get_version(v).arch = prog_arch
 118                 elif '=>' in line:
 119                         prog, requires = line.split('=>')
 120                         prog, version_range = prog.strip().split('[')
 121                         lib, min_v, max_v = requires.split()
 122                         assert version_range.endswith(']')
 123                         version_range = version_range[:-1]
 124                         if ',' in version_range:
 125                                 min_p, max_p = map(int, version_range.split(','))
 126                                 prog_versions = range(min_p, max_p + 1)
 127                         else:
 128                                 prog_versions = [int(version_range)]
 129                         for prog_version in prog_versions:
 130                                 cache.get_prog(prog).get_version(str(prog_version)).add_requires(lib, min_v, max_v)
 131
 132         root = uri_prefix + expected[0][0]
 133
 134         class TestConfig:
 135                 help_with_testing = False
 136                 network_use = model.network_offline
 137                 stores = stores
 138                 iface_cache = cache
 139
 140         s = Solver(TestConfig())
 141         s.solve(root, arch.get_architecture('Linux', 'x86_64'))
 142
 143         if expected[0][1] == 'FAIL':
 144                 assert not s.ready
 145         else:
 146                 assert s.ready
 147
 148                 actual = []
 149                 for iface_uri, impl in s.selections.selections.items():
 150                         actual.append(((iface_uri.rsplit('/', 1)[1]), impl.version))
 151
 152                 expected.sort()
 153                 actual.sort()
 154                 if expected != actual:
 155                         raise Exception("Solve failed:\nExpected: %s\n  Actual: %s" % (expected, actual))
 156         return s
 157
 158 class TestSAT(BaseTest):
 159         def testTrivial(self):
 160                 assertSelection("prog-2", """
 161                         prog: 1 2
 162                         """)
 163
 164         def testSimple(self):
 165                 assertSelection("prog-5, liba-5", """
 166                         prog: 1 2 3 4 5
 167                         liba: 1 2 3 4 5
 168                         prog[1] => liba 0 4
 169                         prog[2] => liba 1 5
 170                         prog[5] => liba 4 5
 171                         """)
 172
 173         def testBestImpossible(self):
 174                 assertSelection("prog-1", """
 175                         prog: 1 2
 176                         liba: 1
 177                         prog[2] => liba 3 4
 178                         """)
 179
 180         def testSlow(self):
 181                 assertSelection("prog-1", """
 182                         prog: 1 2 3 4 5 6 7 8 9
 183                         liba: 1 2 3 4 5 6 7 8 9
 184                         libb: 1 2 3 4 5 6 7 8 9
 185                         libc: 1 2 3 4 5 6 7 8 9
 186                         libd: 1 2 3 4 5 6 7 8 9
 187                         libe: 1
 188                         prog[2,9] => liba 1 9
 189                         liba[1,9] => libb 1 9
 190                         libb[1,9] => libc 1 9
 191                         libc[1,9] => libd 1 9
 192                         libd[1,9] => libe 0 0
 193                         """)
 194
 195         def testNoSolution(self):
 196                 assertSelection("prog-FAIL", """
 197                         prog: 1 2 3
 198                         liba: 1
 199                         prog[1,3] => liba 2 3
 200                         """)
 201
 202         def testBacktrackSimple(self):
 203                 # We initially try liba-3 before learning that it
 204                 # is incompatible and backtracking.
 205                 # We learn that liba-3 doesn't work ever.
 206                 assertSelection("prog-1, liba-2", """
 207                         prog: 1
 208                         liba: 1 2 3
 209                         prog[1] => liba 1 2
 210                         """)
 211
 212         def testBacktrackLocal(self):
 213                 # We initially try liba-3 before learning that it
 214                 # is incompatible and backtracking.
 215                 # We learn that liba-3 doesn't work with prog-1.
 216                 assertSelection("prog-2, liba-2", """
 217                         prog: 1 2
 218                         liba: 1 2 3
 219                         prog[1,2] => liba 1 2
 220                         """)
 221
 222         def testLearning(self):
 223                 # Prog-2 depends on libb and libz, but we can't have both
 224                 # at once. The learning means we don't have to explore every
 225                 # possible combination of liba and libb.
 226                 assertSelection("prog-1", """
 227                         prog: 1 2
 228                         liba: 1 2 3
 229                         libb Linux-i486: 1 2 3
 230                         libz Linux-x86_64: 1 2
 231                         prog[2] => liba 1 3
 232                         prog[2] => libz 1 2
 233                         liba[1,3] => libb 1 3
 234                         """)
 235
 236         def testToplevelConflict(self):
 237                 # We don't detect the conflict until we start solving, but the
 238                 # conflict is top-level so we abort immediately without
 239                 # backtracking.
 240                 assertSelection("prog-FAIL", """
 241                         prog Linux-i386: 1
 242                         liba Linux-x86_64: 1
 243                         prog[1] => liba 1 1
 244                         """)
 245
 246         def testDiamondConflict(self):
 247                 # prog depends on liba and libb, which depend on incompatible
 248                 # versions of libc.
 249                 assertSelection("prog-FAIL", """
 250                         prog: 1
 251                         liba: 1
 252                         libb: 1
 253                         libc: 1 2
 254                         prog[1] => liba 1 1
 255                         prog[1] => libb 1 1
 256                         liba[1] => libc 1 1
 257                         libb[1] => libc 2 3
 258                         """)
 259
 260         def testCoverage(self):
 261                 # Try to trigger some edge cases...
 262
 263                 # An at_most_one clause must be analysed for causing
 264                 # a conflict.
 265                 solver = sat.SATProblem()
 266                 v1 = solver.add_variable("v1")
 267                 v2 = solver.add_variable("v2")
 268                 v3 = solver.add_variable("v3")
 269                 solver.at_most_one([v1, v2])
 270                 solver.add_clause([v1, sat.neg(v3)])
 271                 solver.add_clause([v2, sat.neg(v3)])
 272                 solver.add_clause([v1, v3])
 273                 solver.run_solver(lambda: v3)
 274
 275         def testFailState(self):
 276                 # If we can't select a valid combination,
 277                 # try to select as many as we can.
 278                 s = assertSelection("prog-FAIL", """
 279                         prog: 1 2
 280                         liba: 1 2
 281                         libb: 1 2
 282                         libc: 5
 283                         prog[1,2] => liba 1 2
 284                         liba[1,2] => libb 1 2
 285                         libb[1,2] => libc 0 0
 286                         """)
 287                 assert not s.ready
 288                 selected = {}
 289                 for iface_uri, impl in s.selections.selections.items():
 290                         if impl is not None: impl = impl.version
 291                         selected[iface_uri.rsplit('/', 1)[1]] = impl
 292                 self.assertEqual({
 293                         'prog': '2',
 294                         'liba': '2',
 295                         'libb': '2',
 296                         'libc': None
 297                 }, selected)
 298
 299         def testWatch(self):
 300                 solver = sat.SATProblem()
 301
 302                 a = solver.add_variable('a')
 303                 b = solver.add_variable('b')
 304                 c = solver.add_variable('c')
 305
 306                 # Add a clause. It starts watching the first two variables (a and b).
 307                 # (use the internal function to avoid variable reordering)
 308                 solver._add_clause([a, b, c], False)
 309
 310                 # b is False, so it switches to watching a and c
 311                 solver.add_clause([sat.neg(b)])
 312
 313                 # Try to trigger bug.
 314                 solver.add_clause([c])
 315
 316                 decisions = [a]
 317                 solver.run_solver(lambda: decisions.pop())
 318                 assert not decisions    # All used up
 319
 320                 assert solver.assigns[a].value == True
 321
 322         def testOverbacktrack(self):
 323                 # After learning that prog-3 => m0 we backtrack all the way up to the prog-3
 324                 # assignment, unselecting liba-3, and then select it again.
 325                 assertSelection("prog-3, liba-3, libb-3, libc-1, libz-2", """
 326                         prog: 1 2 3
 327                         liba: 1 2 3
 328                         libb: 1 2 3
 329                         libc Linux-x86_64: 2 3
 330                         libc Linux-i486: 1
 331                         libz Linux-i386: 1 2
 332                         prog[2,3] => liba 1 3
 333                         prog[2,3] => libz 1 2
 334                         liba[1,3] => libb 1 3
 335                         libb[1,3] => libc 1 3
 336                         """)
 337
 338 if __name__ == '__main__':
 339         unittest.main()