view tests/generate-working-copy-states.py @ 34682:7e3001b74ab3

tersestatus: re-implement the functionality to terse the status

The previous terse status implementation was hacking around os.listdir() and was
flaky. There have been a lot of instances of mercurial buildbots failing
and google's internal builds failing because of the
hacky implementation of terse status. Even though I wrote the last
implementation but it was hard for me to find the reason for the flake.

The new implementation can be slower than the old one but is clean and easy to
understand.

In this we create a node object for each directory and create a tree
like structure starting from the root of the working copy. While building the
tree like structure we store some information on the nodes which will be helpful
for deciding later whether we can terse the dir or not.
Once the whole tree is build we traverse and built the list of files for each
status with required tersing.

There is no behaviour change as the old test, test-status-terse.t passes with
the new implementation.

Differential Revision: https://phab.mercurial-scm.org/D985

# Helper script used for generating history and working copy files and content.
# The file's name corresponds to its history. The number of changesets can
# be specified on the command line. With 2 changesets, files with names like
# content1_content2_content1-untracked are generated. The first two filename
# segments describe the contents in the two changesets. The third segment
# ("content1-untracked") describes the state in the working copy, i.e.
# the file has content "content1" and is untracked (since it was previously
# tracked, it has been forgotten).
#
# This script generates the filenames and their content, but it's up to the
# caller to tell hg about the state.
#
# There are two subcommands:
#   filelist <numchangesets>
#   state <numchangesets> (<changeset>|wc)
#
# Typical usage:
#
# $ python $TESTDIR/generate-working-copy-states.py state 2 1
# $ hg addremove --similarity 0
# $ hg commit -m 'first'
#
# $ python $TESTDIR/generate-working-copy-states.py state 2 1
# $ hg addremove --similarity 0
# $ hg commit -m 'second'
#
# $ python $TESTDIR/generate-working-copy-states.py state 2 wc
# $ hg addremove --similarity 0
# $ hg forget *_*_*-untracked
# $ rm *_*_missing-*

from __future__ import absolute_import, print_function

import os
import sys

# Generates pairs of (filename, contents), where 'contents' is a list
# describing the file's content at each revision (or in the working copy).
# At each revision, it is either None or the file's actual content. When not
# None, it may be either new content or the same content as an earlier
# revisions, so all of (modified,clean,added,removed) can be tested.
def generatestates(maxchangesets, parentcontents):
    depth = len(parentcontents)
    if depth == maxchangesets + 1:
        for tracked in ('untracked', 'tracked'):
            filename = "_".join([(content is None and 'missing' or content) for
                                 content in parentcontents]) + "-" + tracked
            yield (filename, parentcontents)
    else:
        for content in ({None, 'content' + str(depth + 1)} |
                      set(parentcontents)):
            for combination in generatestates(maxchangesets,
                                              parentcontents + [content]):
                yield combination

# retrieve the command line arguments
target = sys.argv[1]
maxchangesets = int(sys.argv[2])
if target == 'state':
    depth = sys.argv[3]

# sort to make sure we have stable output
combinations = sorted(generatestates(maxchangesets, []))

# compute file content
content = []
for filename, states in combinations:
    if target == 'filelist':
        print(filename)
    elif target == 'state':
        if depth == 'wc':
            # Make sure there is content so the file gets written and can be
            # tracked. It will be deleted outside of this script.
            content.append((filename, states[maxchangesets] or 'TOBEDELETED'))
        else:
            content.append((filename, states[int(depth) - 1]))
    else:
        print("unknown target:", target, file=sys.stderr)
        sys.exit(1)

# write actual content
for filename, data in content:
    if data is not None:
        f = open(filename, 'wb')
        f.write(data + '\n')
        f.close()
    elif os.path.exists(filename):
        os.remove(filename)