formatter: add overview of API and example as doctest

ui: factor out ui.load() to create a ui without loading configs (API) This allows us to write doctests depending on a ui object, but not on global configs. ui.load() is a class method so we can do wsgiui.load(). All ui() calls but for doctests are replaced with ui.load(). Some of them could be changed to not load configs later.

check-code: add a rule to forbid "cp -r" See the commit message of the previous patch for the reason. In short, according to the current POSIX standard, "-r" is "removed", and "-R" is the current standard way to do "copy file hierarchies".

tests: replace "cp -r" with "cp -R" The POSIX documentation about "cp" [1] says: .... RATIONALE .... Earlier versions of this standard included support for the -r option to copy file hierarchies. The -r option is historical practice on BSD and BSD-derived systems. This option is no longer specified by POSIX.1-2008 but may be present in some implementations. The -R option was added as a close synonym to the -r option, selected for consistency with all other options in this volume of POSIX.1-2008 that do recursive directory descent. The difference between -R and the removed -r option is in the treatment by cp of file types other than regular and directory. It was implementation-defined how the - option treated special files to allow both historical implementations and those that chose to support -r with the same abilities as -R defined by this volume of POSIX.1-2008. The original -r flag, for historic reasons, did not handle special files any differently from regular files, but always read the file and copied its contents. This had obvious problems in the presence of special file types; for example, character devices, FIFOs, and sockets. .... .... Issue 6 The -r option is marked obsolescent. .... Issue 7 .... The obsolescent -r option is removed. .... (No "Issue 8" yet) Therefore it's clear that "cp -R" is strictly better than "cp -r". The issue was discovered when running tests on OS X after 0d87b1caed92. [1]: pubs.opengroup.org/onlinepubs/9699919799/utilities/cp.html

posix: give the cached symlink a real target The NamedTemporaryFile file is cleared up so checklink ends up as a dangling symlink, causing cp -r in tests to complain on both Solaris and OS X. Use a permanent file instead when there is a .hg/cache directory.

shelve: move patch extension to a string constant We are using 'name + ".patch"' pattern throughout the shelve code to identify the existence of a shelve with a particular name. In two cases however we use 'name + ".hg"' instead. This commit makes 'patch' be used in all places and "emphasizes" it by moving 'patch' to live in a constant. Also, this allows to extract file name without extension like this: f[:-(1 + len(patchextension))] instead of: f[:-6] which is good IMO. This is a first patch from this initial "obsshelve" series. This series does not include tests, although locally I have all of test-shelve.t ported to test obs-shelve as well. I will send tests later as a separate series.

merge with stable

shelve: fix use of unexpected working dirs in test-shelve.t Fixing some clowniness where we created ~four levels of nested repos and once (my test case :( ) did not even cd into a created repo.

crecord: change the verb according to the operation This will make crecord consistent with record when being used in the revert situation. It will say "Select hunks to revert / discard" accordingly. This should make the revert crecord interface less confusing.

crecord: change help text for the space key dynamically A follow-up of the previous patch, to make the text simple and clear about whether it's to "select" or "deselect".