mercurial/help/pager.txt

tests: add more tests of copy tracing with removed and re-added files

We had a test where the destination of a copy was removed and then
added back. This patch adds similar cases where the break in history
instead happens to the source file. There are three versions of this:

 1. The break happens before the rename.

 2. The break happens on a branch parallel to the rename (where copy
    tracing is done via the merge base)

 3. The source is added on each side of the merge base. The break in
    history is thus in the form of a deletion when going backwards to
    the merge base and the re-add happens on the other branch.

I've also added calls to `hg graft` in these cases to show the
breakage in issue 6163.

Another factor in these cases is matching nodeid (checked in
copies._tracefile()). I've made two copies each of the cases to show
the impact of that. One of these is the same as a test in
test-rename-merge1.t, so I also deleted that test from there.

Some of these tests currently fail, where "fail" is based on my
current thinking of how things should work. I had initially thought
that we should be more strict about not tracing copies across commits
where the file did not exist, but issue 6163 made me reconsider.

The only test case here that behaved differently in 4.9 is the
exact case reported in issue 6163.

Differential Revision: https://phab.mercurial-scm.org/D6599

Some Mercurial commands can produce a lot of output, and Mercurial will
attempt to use a pager to make those commands more pleasant.

To set the pager that should be used, set the application variable::

  [pager]
  pager = less -FRX

If no pager is set in the user or repository configuration, Mercurial uses the
environment variable $PAGER. If $PAGER is not set, pager.pager from the default
or system configuration is used. If none of these are set, a default pager will
be used, typically `less` on Unix and `more` on Windows.

.. container:: windows

  On Windows, `more` is not color aware, so using it effectively disables color.
  MSYS and Cygwin shells provide `less` as a pager, which can be configured to
  support ANSI color codes.  See :hg:`help config.color.pagermode` to configure
  the color mode when invoking a pager.

You can disable the pager for certain commands by adding them to the
pager.ignore list::

  [pager]
  ignore = version, help, update

To ignore global commands like :hg:`version` or :hg:`help`, you have
to specify them in your user configuration file.

To control whether the pager is used at all for an individual command,
you can use --pager=<value>:

  - use as needed: `auto`.
  - require the pager: `yes` or `on`.
  - suppress the pager: `no` or `off` (any unrecognized value
    will also work).

To globally turn off all attempts to use a pager, set::

  [ui]
  paginate = never

which will prevent the pager from running.