tests/test-simplekeyvaluefile.py

template: add predecessors template

Add a 'predecessors' template that returns the list of all closest known
predecessors for a changectx. The elements of the list are row changectx node id
formatted by default as short nodes.

The "closest predecessors" are the first locally known revisions encountered
while, walking predecessors markers. For example:

  1) If a (A, (B)) markers exists and both A and B are locally known A is a
  closest predecessors of B.

  2) If a (A, (B)) and (B, (C)) markers exists and only A and C are known
  locally, A will be the closest precursors of C.

This logic respect repository filtering. So hidden revision will be skipped by
this logic unless --hidden is specified. Since we only display the visible
predecessors, this template will not display anything in most case. It makes a
good candidate for inclusion in the default log output.

I added a new test-file for testing the precursors in various scenarios. This
test file will also be used for the successors template.

A new "obsutil" module has been added to start gathering utility function
outside of the large obsolete.py module.

from __future__ import absolute_import

import unittest
import silenttestrunner

from mercurial import (
    error,
    scmutil,
)

class mockfile(object):
    def __init__(self, name, fs):
        self.name = name
        self.fs = fs

    def __enter__(self):
        return self

    def __exit__(self, *args, **kwargs):
        pass

    def write(self, text):
        self.fs.contents[self.name] = text

    def read(self):
        return self.fs.contents[self.name]

class mockvfs(object):
    def __init__(self):
        self.contents = {}

    def read(self, path):
        return mockfile(path, self).read()

    def readlines(self, path):
        # lines need to contain the trailing '\n' to mock the real readlines
        return [l for l in mockfile(path, self).read().splitlines(True)]

    def __call__(self, path, mode, atomictemp):
        return mockfile(path, self)

class testsimplekeyvaluefile(unittest.TestCase):
    def setUp(self):
        self.vfs = mockvfs()

    def testbasicwritingiandreading(self):
        dw = {'key1': 'value1', 'Key2': 'value2'}
        scmutil.simplekeyvaluefile(self.vfs, 'kvfile').write(dw)
        self.assertEqual(sorted(self.vfs.read('kvfile').split('\n')),
                         ['', 'Key2=value2', 'key1=value1'])
        dr = scmutil.simplekeyvaluefile(self.vfs, 'kvfile').read()
        self.assertEqual(dr, dw)

    def testinvalidkeys(self):
        d = {'0key1': 'value1', 'Key2': 'value2'}
        with self.assertRaisesRegexp(error.ProgrammingError,
                                     'keys must start with a letter.*'):
            scmutil.simplekeyvaluefile(self.vfs, 'kvfile').write(d)

        d = {'key1@': 'value1', 'Key2': 'value2'}
        with self.assertRaisesRegexp(error.ProgrammingError, 'invalid key.*'):
            scmutil.simplekeyvaluefile(self.vfs, 'kvfile').write(d)

    def testinvalidvalues(self):
        d = {'key1': 'value1', 'Key2': 'value2\n'}
        with self.assertRaisesRegexp(error.ProgrammingError,  'invalid val.*'):
            scmutil.simplekeyvaluefile(self.vfs, 'kvfile').write(d)

    def testcorruptedfile(self):
        self.vfs.contents['badfile'] = 'ababagalamaga\n'
        with self.assertRaisesRegexp(error.CorruptedState,
                                     'dictionary.*element.*'):
            scmutil.simplekeyvaluefile(self.vfs, 'badfile').read()

    def testfirstline(self):
        dw = {'key1': 'value1'}
        scmutil.simplekeyvaluefile(self.vfs, 'fl').write(dw, firstline='1.0')
        self.assertEqual(self.vfs.read('fl'), '1.0\nkey1=value1\n')
        dr = scmutil.simplekeyvaluefile(self.vfs, 'fl')\
                    .read(firstlinenonkeyval=True)
        self.assertEqual(dr, {'__firstline': '1.0', 'key1': 'value1'})

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