chg: exec pager in child process
Before this patch, chg uses the old pager behavior (pre 369741ef7253), which
executes pager in the main process. The user will see the exit code of the
pager, instead of the hg command.
Like 369741ef7253, this patch fixes the behavior by executing the pager in
the child process, and wait for it at the end of the main process.
$ cat >> fakepager.py <<EOF
> import sys
> for line in sys.stdin:
> sys.stdout.write('paged! %r\n' % line)
> EOF
Enable ui.formatted because pager won't fire without it, and set up
pager and tell it to use our fake pager that lets us see when the
pager was running.
$ cat >> $HGRCPATH <<EOF
> [ui]
> formatted = yes
> [extensions]
> pager=
> [pager]
> pager = python $TESTTMP/fakepager.py
> EOF
$ hg init repo
$ cd repo
$ echo a >> a
$ hg add a
$ hg ci -m 'add a'
$ for x in `python $TESTDIR/seq.py 1 10`; do
> echo a $x >> a
> hg ci -m "modify a $x"
> done
By default diff and log are paged, but summary is not:
$ hg diff -c 2 --pager=yes
paged! 'diff -r f4be7687d414 -r bce265549556 a\n'
paged! '--- a/a\tThu Jan 01 00:00:00 1970 +0000\n'
paged! '+++ b/a\tThu Jan 01 00:00:00 1970 +0000\n'
paged! '@@ -1,2 +1,3 @@\n'
paged! ' a\n'
paged! ' a 1\n'
paged! '+a 2\n'
$ hg log --limit 2
paged! 'changeset: 10:46106edeeb38\n'
paged! 'tag: tip\n'
paged! 'user: test\n'
paged! 'date: Thu Jan 01 00:00:00 1970 +0000\n'
paged! 'summary: modify a 10\n'
paged! '\n'
paged! 'changeset: 9:6dd8ea7dd621\n'
paged! 'user: test\n'
paged! 'date: Thu Jan 01 00:00:00 1970 +0000\n'
paged! 'summary: modify a 9\n'
paged! '\n'
$ hg summary
parent: 10:46106edeeb38 tip
modify a 10
branch: default
commit: (clean)
update: (current)
phases: 11 draft
We can enable the pager on summary:
$ hg --config pager.attend-summary=yes summary
paged! 'parent: 10:46106edeeb38 tip\n'
paged! ' modify a 10\n'
paged! 'branch: default\n'
paged! 'commit: (clean)\n'
paged! 'update: (current)\n'
paged! 'phases: 11 draft\n'
If we completely change the attend list that's respected:
$ hg --config pager.attend-diff=no diff -c 2
diff -r f4be7687d414 -r bce265549556 a
--- a/a Thu Jan 01 00:00:00 1970 +0000
+++ b/a Thu Jan 01 00:00:00 1970 +0000
@@ -1,2 +1,3 @@
a
a 1
+a 2
$ hg --config pager.attend=summary diff -c 2
diff -r f4be7687d414 -r bce265549556 a
--- a/a Thu Jan 01 00:00:00 1970 +0000
+++ b/a Thu Jan 01 00:00:00 1970 +0000
@@ -1,2 +1,3 @@
a
a 1
+a 2
If 'log' is in attend, then 'history' should also be paged:
$ hg history --limit 2 --config pager.attend=log
paged! 'changeset: 10:46106edeeb38\n'
paged! 'tag: tip\n'
paged! 'user: test\n'
paged! 'date: Thu Jan 01 00:00:00 1970 +0000\n'
paged! 'summary: modify a 10\n'
paged! '\n'
paged! 'changeset: 9:6dd8ea7dd621\n'
paged! 'user: test\n'
paged! 'date: Thu Jan 01 00:00:00 1970 +0000\n'
paged! 'summary: modify a 9\n'
paged! '\n'
Possible bug: history is explicitly ignored in pager config, but
because log is in the attend list it still gets pager treatment.
$ hg history --limit 2 --config pager.attend=log \
> --config pager.ignore=history
paged! 'changeset: 10:46106edeeb38\n'
paged! 'tag: tip\n'
paged! 'user: test\n'
paged! 'date: Thu Jan 01 00:00:00 1970 +0000\n'
paged! 'summary: modify a 10\n'
paged! '\n'
paged! 'changeset: 9:6dd8ea7dd621\n'
paged! 'user: test\n'
paged! 'date: Thu Jan 01 00:00:00 1970 +0000\n'
paged! 'summary: modify a 9\n'
paged! '\n'
Possible bug: history is explicitly marked as attend-history=no, but
it doesn't fail to get paged because log is still in the attend list.
$ hg history --limit 2 --config pager.attend-history=no
paged! 'changeset: 10:46106edeeb38\n'
paged! 'tag: tip\n'
paged! 'user: test\n'
paged! 'date: Thu Jan 01 00:00:00 1970 +0000\n'
paged! 'summary: modify a 10\n'
paged! '\n'
paged! 'changeset: 9:6dd8ea7dd621\n'
paged! 'user: test\n'
paged! 'date: Thu Jan 01 00:00:00 1970 +0000\n'
paged! 'summary: modify a 9\n'
paged! '\n'
Possible bug: disabling pager for log but enabling it for history
doesn't result in history being paged.
$ hg history --limit 2 --config pager.attend-log=no \
> --config pager.attend-history=yes
changeset: 10:46106edeeb38
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: modify a 10
changeset: 9:6dd8ea7dd621
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: modify a 9
Pager with color enabled allows colors to come through by default,
even though stdout is no longer a tty.
$ cat >> $HGRCPATH <<EOF
> [extensions]
> color=
> [color]
> mode = ansi
> EOF
$ hg log --limit 3
paged! '\x1b[0;33mchangeset: 10:46106edeeb38\x1b[0m\n'
paged! 'tag: tip\n'
paged! 'user: test\n'
paged! 'date: Thu Jan 01 00:00:00 1970 +0000\n'
paged! 'summary: modify a 10\n'
paged! '\n'
paged! '\x1b[0;33mchangeset: 9:6dd8ea7dd621\x1b[0m\n'
paged! 'user: test\n'
paged! 'date: Thu Jan 01 00:00:00 1970 +0000\n'
paged! 'summary: modify a 9\n'
paged! '\n'
paged! '\x1b[0;33mchangeset: 8:cff05a6312fe\x1b[0m\n'
paged! 'user: test\n'
paged! 'date: Thu Jan 01 00:00:00 1970 +0000\n'
paged! 'summary: modify a 8\n'
paged! '\n'
Pager works with shell aliases.
$ cat >> $HGRCPATH <<EOF
> [alias]
> echoa = !echo a
> EOF
$ hg echoa
a
$ hg --config pager.attend-echoa=yes echoa
paged! 'a\n'
Pager works with hg aliases including environment variables.
$ cat >> $HGRCPATH <<'EOF'
> [alias]
> printa = log -T "$A\n" -r 0
> EOF
$ A=1 hg --config pager.attend-printa=yes printa
paged! '1\n'
$ A=2 hg --config pager.attend-printa=yes printa
paged! '2\n'
Pager should not override the exit code of other commands
$ cat >> $TESTTMP/fortytwo.py <<'EOF'
> from mercurial import cmdutil, commands
> cmdtable = {}
> command = cmdutil.command(cmdtable)
> @command('fortytwo', [], 'fortytwo', norepo=True)
> def fortytwo(ui, *opts):
> ui.write('42\n')
> return 42
> EOF
$ cat >> $HGRCPATH <<'EOF'
> [extensions]
> fortytwo = $TESTTMP/fortytwo.py
> EOF
$ hg fortytwo --pager=on
paged! '42\n'
[42]