PATCH: 3.0.6-pre-3: mainly history bug fixes

PATCH: 3.0.6-pre-3: mainly history bug fixes

[Wayne Davison]

I believe I've managed to distill most of the bug fixes that were
included in my previous history changes into a separate patch for
3.0.6.  I haven't had much of a chance to test this yet, but since
most of this is lifted from my previous changes, it should be OK.

Most of these changes were originally lifted from the 3.1.x source.
Some of the more trivial changes are included just to make it easier
to compare the 3.1.x source to the 3.0.x source with more manageable
diffs (e.g. when an int variable turned into a thingy in 3.1.x, I
went ahead and moved the int variable onto its own line in the 3.0.x
source in order to make the rest of the declarations match up).

One non-bugfix that is included here is the change I made to the
EXTENDED_HISTORY output format where it writes the finish time in
elapsed seconds instead of epoch seconds -- I figured if this is
going to change in 3.1.x, we might as well get it going in 3.0.6 too.
Unfortunately I don't seem to have lifted the documentation change
for this yet, so I'll send a patch for that later.

..wayne..

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end
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Re: PATCH: 3.0.6-pre-3: mainly history bug fixes

[Bart Schaefer]

On Jun 2,  2:55am, Wayne Davison wrote:
} Subject: PATCH: 3.0.6-pre-3: mainly history bug fixes
}
} I believe I've managed to distill most of the bug fixes that were
} included in my previous history changes into a separate patch for
} 3.0.6.  I haven't had much of a chance to test this yet, but since
} most of this is lifted from my previous changes, it should be OK.
} 
} Most of these changes were originally lifted from the 3.1.x source.

Pardon my paranoia, but ...

Something I don't want to accidentally do is fold in the history search
change (whole words at beginning of line) that caused so much complaint
and eventual back-patching.  I don't *think* I see it in here anywhere,
but if you can reassure me, please do.

} One non-bugfix that is included here is the change I made to the
} EXTENDED_HISTORY output format where it writes the finish time in
} elapsed seconds instead of epoch seconds -- I figured if this is
} going to change in 3.1.x, we might as well get it going in 3.0.6 too.

I hadn't thought much about this before, but what's going to happen when
somebody with this option set fires up a new zsh and it loads his existing
old-format .zhistory?  All the timestamps are going to look like garbage,
aren't they?

Seems to me that a change like this should be written in different syntax,
so that there's no chance of confusing the old numbers for the new.

-- 
Bart Schaefer                                 Brass Lantern Enterprises
http://www.well.com/user/barts              http://www.brasslantern.com

Re: PATCH: 3.0.6-pre-3: mainly history bug fixes

[Wayne Davison]

On Thu, 3 Jun 1999, Bart Schaefer wrote:
> Something I don't want to accidentally do is fold in the history
> search change (whole words at beginning of line) that caused so
> much complaint and eventual back-patching.  I don't *think* I see
> it in here anywhere, but if you can reassure me, please do.

Quite correct, I did not include that change, nor any history change
that was not a bug fix or a code optimization.  For example, several
functions now properly use the numeric prefix that had previously
ignored it.  Also, the majority of the differences in zle_hist.c was
from a unification of the upline/downline code into separate
functions so that the formerly-duplicated code would not continue to
diverge (it was inconsistent in one case, I believe).

> what's going to happen when somebody with this option set fires up
> a new zsh and it loads his existing old-format .zhistory?

The new code is smart enough to treat a finish length that is >= the
start time as the old format.  This should be OK, since I don't
believe that people will be running a program continuously for over
29 years.

Going back from a new shell with this new EXTENDED_HISTORY format to
an old shell without it can cause the finish times to read in as
very early dates, but I wasn't particularly concerned about this.
Do you feel differently?

..wayne..

Re: PATCH: 3.0.6-pre-3: mainly history bug fixes

[Bart Schaefer]

On Jun 3,  8:11pm, Wayne Davison wrote:
} Subject: Re: PATCH: 3.0.6-pre-3: mainly history bug fixes
}
} On Thu, 3 Jun 1999, Bart Schaefer wrote:
} > Something I don't want to accidentally do is fold in the history
} > search change (whole words at beginning of line)
} 
} Quite correct, I did not include that change, nor any history change
} that was not a bug fix or a code optimization.

Thank you (both for doing it and reassuring me about it).

} > what's going to happen when somebody with this option set fires up
} > a new zsh and it loads his existing old-format .zhistory?
} 
} The new code is smart enough to treat a finish length that is >= the
} start time as the old format.

Aha.

} Going back from a new shell with this new EXTENDED_HISTORY format to
} an old shell without it can cause the finish times to read in as
} very early dates, but I wasn't particularly concerned about this.
} Do you feel differently?

I'm thinking about it ... of course one hopes that there won't be any
reason to go backwards ... it's impossible to make such a change in a
forwards-compatible way (such that the old version won't be confused)
so there's no point in doing more than you have; the question is if the
change should be made at all.

Here's a thought that just occurred to me:  What if we have 3.0.6 keep
writing hist files in the old format, but treat a finish time less than
the start time as the new format?  Then 3.0.6 and 3.1.6 will be able to
exchange history files with each other.  A transition phase like that
seems worthwhile to me.

-- 
Bart Schaefer                                 Brass Lantern Enterprises
http://www.well.com/user/barts              http://www.brasslantern.com