Bug #124447 for podlators: Pod::Text::Termcap explicit width control is faulty

"eponymous alias via RT" <bug-podlators@rt.cpan.org> writes: Show quoted text
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Wow, this has been broken since the 2.0.0 release. Nice find! Fixed in Git for the next release, which should be fairly soon. -- #!/usr/bin/perl -- Russ Allbery, Just Another Perl Hacker $^=q;@!>~|{>krw>yn{u<$$<[~||<Juukn{=,<S~|}<Jwx}qn{<Yn{u<Qjltn{ > 0gFzD gD, 00Fz, 0,,( 0hF 0g)F/=, 0> "L$/GEIFewe{,$/ 0C$~> "@=,m,|,(e 0.), 01,pnn,y{ rw} >;,$0=q,$,,($_=$^)=~y,$/ C-~><@=\n\r,-~$:-u/ #y,d,s,(\$.),$1,gee,print

On Sat Feb 17 17:39:04 2018, RRA wrote: Show quoted text
There is a further problem with the width option in Pod::Text::Termcap, this one involving how wrapping is implemented. I am using Pod::Text::Termcap v4.10 modified with the simple change described in bug #124447 (this one) to get the package to pay attention to the width parameter. I have a bunch of =item lines that contain multi-word tags with many embedded color changes (generated by B<words> and I<words> elements). I observe that when my formatted POD is output to an xterm, text in open paragraphs manages to use the Pod::Text::Termcap::wrap() routine, and the characters comprising escape sequences for color changes embedded in that text do not cause early wrapping. However, for some reason the text in my =item tags seems to be processed instead by Pod::Text::wrap(), meaning I get wrapping much too soon in this text. I don't understand the internals of these two packages well enough to know why the one case is working while the other is not, nor to understand how to force the wrap() override to work in the second case. Here is a small test item, wherein on an 80-character terminal, I get the ellipsis at the end wrapped onto the next line when it shouldn't be (and isn't, if the terminal is say 100 characters wide). =over 4 =item B<autosetup print analysis> [B<-e>|B<-f>|B<-u>] I<hostname> ... =back

On Sun Feb 18 15:45:47 2018, RRA wrote: Show quoted text
I'm very happy to see these corrections going in. So much so, that I just downloaded the current GitHub copy (pre-v4.11) and tried it out. It's working well now for the reported problems. That said, I observe a residual issue, that of sometimes losing color when a long =item line is wrapped and the output is run through certain pagers. Here is a variety of test lines so you can see when the problem does and does not occur. =over 4 =item B<autosetup status> [B<-t>] {B<-a>|[B<-e>|B<-f>|B<-u>] I<hostname> ...} =item B<autosetup validate> I<hostname> ... =item B<autosetup install -p> I<patternfile> I<hostname> ... =item B<autosetup print analysis> [B<-e>|B<-f>|B<-u>] I<hostname> ... =item B<autosetup install -p standard_test_only_trigger host1 host2 host3> =back When that last item in particular gets wrapped because the terminal window is not wide enough to contain the entire item (say, only 60 characters wide, set by an explicit width option in the Pod::Text::Termcap constructor), the second and later lines of that item may lose their coloring. The issue seems to be that if the content enclosed in my B<> formatting code contains a space character, then if the wrapping breaks on such a space, the coloring may be lost. I suppose the same would be true with I<>. Here is the raw wrapped text being displayed, with escape characters made visible as ESC: ESC[1mautosetup install -p standard_test_only_trigger host1 host2 host3ESC[0m I'm using an xterm and piping the output to "less -R", and that's the context where the problem shows up. "more -f" doesn't have this problem. This is clearly an issue most directly attributable to the pager, not to Pod::Text::Termcap. But you may want to consider some defensive measures, namely if a wrap occurs while $$self{BOLD} or $$self{UNDL} is in effect, close out that line with $$self{NORM} and start the next line (after leading spaces) with the $$self{BOLD} or $$self{UNDL} that was previously in effect. To be precise, this problem is happening with both less version 436, which is present in both RHEL 5.11 and CentOS 6.9, and with less version 458, which is present in CentOS 7.4.1708 (the most current CentOS release). I have also downloaded, compiled, and tested less version 530, the current upstream release (2018-02-17), and it behaves the same way. I suppose a bug could be filed on that end as well. But these older versions of the pager will be with us for a long time, so having the Perl package be extra-careful seems like a sensible precaution.

On Sun, 3/18/18, Russ Allbery via RT <bug-podlators@rt.cpan.org> wrote: Show quoted text
I have downloaded and installed the current GitHub code and run a few quick tests. It's not a full test suite or anything, but it's at least working fine in the context I see.

Fixed in 4.11.