view tests/test-config-env.py @ 50741:bca4037306da stable

rust-revlog: fix incorrect results with NULL_NODE prefixes

In case a short hash is a prefix of `NULL_NODE`, the correct revision
number lookup is `NULL_REVISION` only if there is no match in the nodemap.
Indeed, if there is a single nodemap match, then it is an ambiguity with the
always matching `NULL_NODE`.

Before this change, using the Mercurial development repository as a testbed (it
has public changesets with node ID starting with `0005` and `0009`), this is
what `rhg` did (plain `hg` provided for reference)

```
$ rust/target/debug/rhg cat -r 000 README
README: no such file in rev 000000000000
$ hg cat -r 000 README
abort: ambiguous revision identifier: 000
```

Here is the expected output for `rhg` on ambiguous prefixes (again, before
this change):

```
$ rust/target/debug/rhg cat -r 0001 README
abort: ambiguous revision identifier: 0001
```

The test provided by 8c29af0f6d6e in `test-rhg.t` could become flaky with
this change, unless all hashes are fixed. We expect reviewers to be more
sure about that than we are.

# Test the config layer generated by environment variables


import os

from mercurial import (
    encoding,
    extensions,
    rcutil,
    ui as uimod,
    util,
)

from mercurial.utils import procutil

testtmp = encoding.environ[b'TESTTMP']

# prepare hgrc files
def join(name):
    return os.path.join(testtmp, name)


with open(join(b'sysrc'), 'wb') as f:
    f.write(b'[ui]\neditor=e0\n[pager]\npager=p0\n')

with open(join(b'userrc'), 'wb') as f:
    f.write(b'[ui]\neditor=e1')

# replace rcpath functions so they point to the files above
def systemrcpath():
    return [join(b'sysrc')]


def userrcpath():
    return [join(b'userrc')]


extensions.wrapfunction(rcutil, 'default_rc_resources', lambda orig: [])

rcutil.systemrcpath = systemrcpath
rcutil.userrcpath = userrcpath

# utility to print configs
def printconfigs(env):
    encoding.environ = env
    rcutil._rccomponents = None  # reset cache
    ui = uimod.ui.load()
    for section, name, value in ui.walkconfig():
        source = ui.configsource(section, name)
        procutil.stdout.write(
            b'%s.%s=%s # %s\n' % (section, name, value, util.pconvert(source))
        )
    procutil.stdout.write(b'\n')


# environment variable overrides
printconfigs({})
printconfigs({b'EDITOR': b'e2', b'PAGER': b'p2'})