chg's runpager implementation is different. It behaves differently for the
"shell=False, command not found" case.
Differential Revision: https://phab.mercurial-scm.org/D911
The `pushbuffer`, `popbuffer` APIs are intended to capture internal output.
They will prevent `ui.write` from writing to the actual `ui.fout`. So a
pager won't receive the output and do the right thing. In general, it does
not make sense to start a pager if ui is in the "pushbuffer" mode.
Differential Revision: https://phab.mercurial-scm.org/D574
Before this patch, explicit --pager=on is unintentionally ignored by
any disabling factor, even if priority of it is less than --pager=on
(e.g. "[ui] paginate = off").
cmdutil.command wasn't a member of the registrar framework only for a
historical reason. Let's make that happen. This patch keeps cmdutil.command
as an alias for extension compatibility.
This aligns with what we do for color (see cea7a760c58d). Pager is a central
enough notion that having the master config in the [ui] section makes senses. It
will helps with consistency, discoverability. It will also help having a simple
and clear example hgrc mentioning pager.
The previous form of the option had never been released in a non-rc version but
we keep it around for convenience. If both are set, 'ui.pager' take priority.
Previously, 'ui.color=yes' meant "always show color", While
"ui.color=auto" meant "use color automatically when it appears
sensible".
This feels problematic to some people because if an administrator has
disabled color with "ui.color=off", and a user turn it back on using
"color=on", it will get surprised (because it breaks their output when
redirected to a file.) This patch changes ui.color=true to only move the
default value of --color from "never" to "auto".
I'm not really in favor of this changes as I suspect the above case will
be pretty rare and I would rather keep the logic simpler. However, I'm
providing this patch to help the 4.2 release in the case were others
decide to make this changes.
Users that want to force colors without specifying --color on the
command line can use the 'ui.formatted' config knob, which had to be
enabled in a handful of tests for this patch.
Nice summary table (credit: Augie Fackler)
That is, before this patch:
+--------------------+--------------------+--------------------+
| | not a tty | a tty |
| | --color not set | --color not set |
| | | |
+--------------------+--------------------+--------------------+
| [ui] | | |
| color (not set) | no color | no color |
| | | |
+--------------------+--------------------+--------------------+
| [ui] | | |
| color = auto | no color | color |
| | | |
+--------------------+--------------------+--------------------+
| [ui] | | |
| color = yes | *color* | color |
| | | |
+--------------------+--------------------+--------------------+
| [ui] | | |
| color = no | no color | no color |
| | | |
+--------------------+--------------------+--------------------+
(if --color is specified, it always clobbers the setting in [ui])
and after this patch:
+--------------------+--------------------+--------------------+
| | not a tty | a tty |
| | --color not set | --color not set |
| | | |
+--------------------+--------------------+--------------------+
| [ui] | | |
| color (not set) | no color | no color |
| | | |
+--------------------+--------------------+--------------------+
| [ui] | | |
| color = auto | no color | color |
| | | |
+--------------------+--------------------+--------------------+
| [ui] | | |
| color = yes | *no color* | color |
| | | |
+--------------------+--------------------+--------------------+
| [ui] | | |
| color = no | no color | no color |
| | | |
+--------------------+--------------------+--------------------+
(if --color is specified, it always clobbers the setting in [ui])
Color support is all in core for a couple of months. I've browsed the bug tracker
without finding any blocker bug. So I'm moving forward and enable color on by
default before '4.2-rc'. In the worse case, having it on in the release
candidate will help us to find blocker bug and we can turn it off for the final
release.
I remember people talking about issue with Windows during the freeze so I'm
keeping it off by default on that OS.
We could do various cleaning of the color used and the label issued. However
the label are probably already in our backward compatibility envelope since the
color extensions has been around since for ever and I do not think the color
choice themself should be considered BC. So I think we should rather gives color
to all user sooner than later.
A couple of test needs to be updated to avoid having color related control code
spoil the tested output.
man(1) behaves as poorly as Mercurial without this change. This cribs
from git's run-command[0], which has a list of characters that imply a
string that needs to be run using 'sh -c'. If none of those characters
are present in the command string, we can use shell=False mode on
subprocess and get significantly better error messages (see the test)
when the pager process is invalid. With a complicated pager command
(that contains one of the unsafe characters), we behave as we do today
(which is no worse than git manages.)
I briefly tried tapdancing in a thread to catch early pager exits, but
it's just too perilous: you get races between fd duping operations and
a bad pager exiting, and it's too hard to differentiate between a
slow-bad-pager result and a fast-human-quit-pager-early result.
I've observed some weird variation in exit code handling in the "bad
experience" case in test-pager.t: on my Mac hg predictably exits
nonzero, but on Linux hg always exits zero in that case. For now,
we'll work around it with || true. :(
0: cddbda4bc8/run-command.c (L201)
When the old pager extension is enabled, I think we should try to be
as BC as reasonable. To help with that, this patch brings back
test-pager.t as of 45ff5bf9e9c2 (pager: add a test of --pager=no
functionality, 2017-02-06), but under the name test-pager-legacy.t
However, since the behavior has changed in a few cases (notably by no
longer respecting pager.attend), the file is modified to work with the
current version. We will recover some lost BC in coming patches.
Also, to make sure the in-core pager does not depend on the pager
extension being enabled, this patch disables the extension in
test-pager.t. It turns out that pager.attend-$cmd was only supported
when the pager extension was enabled, so the tests are updated to
reflect that. We will need to decide what to do with these.
We've made chg utilize the common code path implemented in pager.py (by
e8fb65f5e551 and e97133c7a9dc), but the chg server does not always start
with a tty. Because of this, uisetup() of the pager extension could be
skipped on the chg server.
Kudos given to Sean Farley for dogfooding new chg and spotting this problem.
Before this patch, chg uses the old pager behavior (pre 55f6f7fb60d2), which
executes pager in the main process. The user will see the exit code of the
pager, instead of the hg command.
Like 55f6f7fb60d2, this patch fixes the behavior by executing the pager in
the child process, and wait for it at the end of the main process.
Before this patch, we may or may not load extensions for shell aliases
depending on whether the command is abbreviated or not.
Loading extensions may have useful side effects to shell aliases. For example,
the pager extension does not work for shell aliases.
This patch removes the code checking shell aliases before loading extensions
to give the user a more consistent experience. It may hurt performance for
shell aliases a bit without chg but the correctness seems worth it. It will
also make the behavior consistent with chg since chg will always load all
extensions before running commands.
