Re: Problems with move_it_in_display_line_to X when tabs exist.

[Keith David Bershatsky <esq@lawlist.com>]

Thank you, Eli, for your help.

I will work on this over the next few days as time permits and report back.

Keith

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DATE:  [11-29-2017 10:04:14] <29 Nov 2017 20:04:14 +0200>
FROM:  Eli Zaretskii <eliz@gnu.org>
> 
> > Date: Tue, 28 Nov 2017 22:12:35 -0800
> > From: Keith David Bershatsky <esq@lawlist.com>
> > 
> > I can see that X and/or HPOS are wrong when tabs are present on the current line because I get superimposed letters and double of the same word slightly off to the left and/or the right of where the word should be.
> > 
> > HYPOTHESIS:  I would venture to say that what is displayed on screen does _not_ coincide with what IT reports when running move_it_in_display_line_to.
> 
> Does this happen only when line numbers are displayed?
> 
> In any case, your description provides a lot of details that are hard
> to reason about, because most of the code is not shown.  OTOH, if
> indeed there's a bug in move_it_in_display_line_to, then presenting
> evidence for it is very simple: show a line of text and its line
> number, and then show the X and HPOS values for each tab in that line
> as calculated by move_it_in_display_line_to vs the same values in a
> displayed line.  (For the latter, you can use the pgrowx command
> defined in src/.gdbinit, or manually display the values using the
> debugger.)
> 
> If you do that, any mismatches between displaying a line and moving
> through it with move_it_in_display_line_to will be immediately
> apparent, and it should be easy to fix them.