tests/test-trusted.py

show: implement "stack" view

People often want to know what they are working on *now*. As part of
this, they also commonly want to know how that work is related to other
changesets in the repo so they can perform common actions like rebase,
histedit, and merge.

`hg show work` made headway into this space. However, it is geared
towards a complete repo view as opposed to just the current line of
work. If you have a lot of in-flight work or the repo has many heads,
the output can be overwhelming. The closest thing Mercurial has to
"show me the current thing I'm working on" that doesn't require custom
revsets is `hg qseries`. And this requires MQ, which completely changes
workflows and repository behavior and has horrible performance on large
repos. But as sub-optimal as MQ is, it does some things right, such as
expose a model of the repo that is easy for people to reason about.
This simplicity is why I think a lot of people prefer to use MQ, despite
its shortcomings.

One common development workflow is to author a series of linear
changesets, using bookmarks, branches, anonymous heads, or even topics
(3rd party extension). I'll call this a "stack." You periodically
rewrite history in place (using `hg histedit`) and reparent the stack
against newer changesets (using `hg rebase`). This workflow can be
difficult because there is no obvious way to quickly see the current
"stack" nor its relation to other changesets. Figuring out arguments to
`hg rebase` can be difficult and may require highlighting and pasting
multiple changeset nodes to construct a command.

The goal of this commit is to make stack based workflows simpler
by exposing a view of the current stack and its relationship to
other releant changesets, notably the parent of the base changeset
in the stack and newer heads that the stack could be rebased or merged
into.

Introduced is the `hg show stack` view. Essentially, it finds all
mutable changesets from the working directory revision in both
directions, stopping at a merge or branch point. This limits the
revisions to a DAG linear range.

The stack is rendered as a concise list of changesets. Alongside the
stack is a visualization of the DAG, similar to `hg log -G`.

Newer public heads from the branch point of the stack are rendered
above the stack. The presence of these heads helps people understand
the DAG model and the relationship between the stack and changes made
since the branch point of that stack. If the "rebase" command is
available, a `hg rebase` command is printed for each head so a user
can perform a simple copy and paste to perform a rebase.

This view is alpha quality. There are tons of TODOs documented
inline. But I think it is good enough for a first iteration.

# Since it's not easy to write a test that portably deals
# with files from different users/groups, we cheat a bit by
# monkey-patching some functions in the util module

from __future__ import absolute_import, print_function

import os
from mercurial import (
    error,
    ui as uimod,
    util,
)

hgrc = os.environ['HGRCPATH']
f = open(hgrc)
basehgrc = f.read()
f.close()

def testui(user='foo', group='bar', tusers=(), tgroups=(),
           cuser='foo', cgroup='bar', debug=False, silent=False,
           report=True):
    # user, group => owners of the file
    # tusers, tgroups => trusted users/groups
    # cuser, cgroup => user/group of the current process

    # write a global hgrc with the list of trusted users/groups and
    # some setting so that we can be sure it was read
    f = open(hgrc, 'w')
    f.write(basehgrc)
    f.write('\n[paths]\n')
    f.write('global = /some/path\n\n')

    if tusers or tgroups:
        f.write('[trusted]\n')
        if tusers:
            f.write('users = %s\n' % ', '.join(tusers))
        if tgroups:
            f.write('groups = %s\n' % ', '.join(tgroups))
    f.close()

    # override the functions that give names to uids and gids
    def username(uid=None):
        if uid is None:
            return cuser
        return user
    util.username = username

    def groupname(gid=None):
        if gid is None:
            return 'bar'
        return group
    util.groupname = groupname

    def isowner(st):
        return user == cuser
    util.isowner = isowner

    # try to read everything
    #print '# File belongs to user %s, group %s' % (user, group)
    #print '# trusted users = %s; trusted groups = %s' % (tusers, tgroups)
    kind = ('different', 'same')
    who = ('', 'user', 'group', 'user and the group')
    trusted = who[(user in tusers) + 2*(group in tgroups)]
    if trusted:
        trusted = ', but we trust the ' + trusted
    print('# %s user, %s group%s' % (kind[user == cuser], kind[group == cgroup],
                                     trusted))

    u = uimod.ui.load()
    u.setconfig('ui', 'debug', str(bool(debug)))
    u.setconfig('ui', 'report_untrusted', str(bool(report)))
    u.readconfig('.hg/hgrc')
    if silent:
        return u
    print('trusted')
    for name, path in u.configitems('paths'):
        print('   ', name, '=', util.pconvert(path))
    print('untrusted')
    for name, path in u.configitems('paths', untrusted=True):
        print('.', end=' ')
        u.config('paths', name) # warning with debug=True
        print('.', end=' ')
        u.config('paths', name, untrusted=True) # no warnings
        print(name, '=', util.pconvert(path))
    print()

    return u

os.mkdir('repo')
os.chdir('repo')
os.mkdir('.hg')
f = open('.hg/hgrc', 'w')
f.write('[paths]\n')
f.write('local = /another/path\n\n')
f.close()

#print '# Everything is run by user foo, group bar\n'

# same user, same group
testui()
# same user, different group
testui(group='def')
# different user, same group
testui(user='abc')
# ... but we trust the group
testui(user='abc', tgroups=['bar'])
# different user, different group
testui(user='abc', group='def')
# ... but we trust the user
testui(user='abc', group='def', tusers=['abc'])
# ... but we trust the group
testui(user='abc', group='def', tgroups=['def'])
# ... but we trust the user and the group
testui(user='abc', group='def', tusers=['abc'], tgroups=['def'])
# ... but we trust all users
print('# we trust all users')
testui(user='abc', group='def', tusers=['*'])
# ... but we trust all groups
print('# we trust all groups')
testui(user='abc', group='def', tgroups=['*'])
# ... but we trust the whole universe
print('# we trust all users and groups')
testui(user='abc', group='def', tusers=['*'], tgroups=['*'])
# ... check that users and groups are in different namespaces
print("# we don't get confused by users and groups with the same name")
testui(user='abc', group='def', tusers=['def'], tgroups=['abc'])
# ... lists of user names work
print("# list of user names")
testui(user='abc', group='def', tusers=['foo', 'xyz', 'abc', 'bleh'],
       tgroups=['bar', 'baz', 'qux'])
# ... lists of group names work
print("# list of group names")
testui(user='abc', group='def', tusers=['foo', 'xyz', 'bleh'],
       tgroups=['bar', 'def', 'baz', 'qux'])

print("# Can't figure out the name of the user running this process")
testui(user='abc', group='def', cuser=None)

print("# prints debug warnings")
u = testui(user='abc', group='def', cuser='foo', debug=True)

print("# report_untrusted enabled without debug hides warnings")
u = testui(user='abc', group='def', cuser='foo', report=False)

print("# report_untrusted enabled with debug shows warnings")
u = testui(user='abc', group='def', cuser='foo', debug=True, report=False)

print("# ui.readconfig sections")
filename = 'foobar'
f = open(filename, 'w')
f.write('[foobar]\n')
f.write('baz = quux\n')
f.close()
u.readconfig(filename, sections=['foobar'])
print(u.config('foobar', 'baz'))

print()
print("# read trusted, untrusted, new ui, trusted")
u = uimod.ui.load()
u.setconfig('ui', 'debug', 'on')
u.readconfig(filename)
u2 = u.copy()
def username(uid=None):
    return 'foo'
util.username = username
u2.readconfig('.hg/hgrc')
print('trusted:')
print(u2.config('foobar', 'baz'))
print('untrusted:')
print(u2.config('foobar', 'baz', untrusted=True))

print()
print("# error handling")

def assertraises(f, exc=error.Abort):
    try:
        f()
    except exc as inst:
        print('raised', inst.__class__.__name__)
    else:
        print('no exception?!')

print("# file doesn't exist")
os.unlink('.hg/hgrc')
assert not os.path.exists('.hg/hgrc')
testui(debug=True, silent=True)
testui(user='abc', group='def', debug=True, silent=True)

print()
print("# parse error")
f = open('.hg/hgrc', 'w')
f.write('foo')
f.close()

try:
    testui(user='abc', group='def', silent=True)
except error.ParseError as inst:
    print(inst)

try:
    testui(debug=True, silent=True)
except error.ParseError as inst:
    print(inst)

print()
print('# access typed information')
with open('.hg/hgrc', 'w') as f:
    f.write('''\
[foo]
sub=main
sub:one=one
sub:two=two
path=monty/python
bool=true
int=42
bytes=81mb
list=spam,ham,eggs
''')
u = testui(user='abc', group='def', cuser='foo', silent=True)
def configpath(section, name, default=None, untrusted=False):
    path = u.configpath(section, name, default, untrusted)
    if path is None:
        return None
    return util.pconvert(path)

print('# suboptions, trusted and untrusted')
trusted = u.configsuboptions('foo', 'sub')
untrusted = u.configsuboptions('foo', 'sub', untrusted=True)
print(
    (trusted[0], sorted(trusted[1].items())),
    (untrusted[0], sorted(untrusted[1].items())))
print('# path, trusted and untrusted')
print(configpath('foo', 'path'), configpath('foo', 'path', untrusted=True))
print('# bool, trusted and untrusted')
print(u.configbool('foo', 'bool'), u.configbool('foo', 'bool', untrusted=True))
print('# int, trusted and untrusted')
print(
    u.configint('foo', 'int', 0),
    u.configint('foo', 'int', 0, untrusted=True))
print('# bytes, trusted and untrusted')
print(
    u.configbytes('foo', 'bytes', 0),
    u.configbytes('foo', 'bytes', 0, untrusted=True))
print('# list, trusted and untrusted')
print(
    u.configlist('foo', 'list', []),
    u.configlist('foo', 'list', [], untrusted=True))