[bug #52517] src: adjustments of a line can break down if it contains "\~"

[Bjarni Ingi Gislason]

URL:
  <http://savannah.gnu.org/bugs/?52517>

                 Summary: src: adjustments of a line can break down if it
contains "\~"
                 Project: GNU troff
            Submitted by: bjarniig
            Submitted on: Sun 26 Nov 2017 06:24:27 PM UTC
                Category: Core
                Severity: 3 - Normal
              Item Group: Incorrect behaviour
                  Status: None
                 Privacy: Public
             Assigned to: None
             Open/Closed: Open
         Discussion Lock: Any
         Planned Release: None

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Details:

  I discovered this bug while replacing ".nh/.hy" pairs with "\%" in the
"contrib/groffer/groffer.1.man" file.

  Backspaces can been seen in the output if it is piped though "od -tcx1".

  Test file (hyphen.gro):

.pl 10
.\"ll 1n
.tm hyphenation at start is \n[.hy]
.hy 12
.tm Extent of hyphenation is (.hy) is \n[.hy]
.nr LL 10
.ll \n[LL]
.\".na
.while \n[LL]>0 \{\
.tm Line length is \n[LL]
www\~mode
.nr LL \n[LL]-1
.ll \n[LL]
.\}

  Output is also in the attachment.

command line: test-groff hyphen.gro

Output (without backspaces):


hyphenation at start is 14
Extent of hyphenation is (.hy) is 12
Line length is 10
Line length is 9
Line length is 8
Line length is 7
../testen/hyphen.gro:11: backtrace: while loop
../testen/hyphen.gro:14: warning [p 1, 0.5i]: can't break line
Line length is 6
../testen/hyphen.gro:11: backtrace: while loop
../testen/hyphen.gro:14: warning [p 1, 0.7i]: can't break line
Line length is 5
../testen/hyphen.gro:11: backtrace: while loop
../testen/hyphen.gro:14: warning [p 1, 0.8i]: can't break line
Line length is 4
../testen/hyphen.gro:11: backtrace: while loop
../testen/hyphen.gro:14: warning [p 1, 1.0i]: can't break line
Line length is 3
../testen/hyphen.gro:11: backtrace: while loop
../testen/hyphen.gro:14: warning [p 1, 1.2i]: can't break line
Line length is 2
../testen/hyphen.gro:11: backtrace: while loop
../testen/hyphen.gro:14: warning [p 1, 1.3i]: can't break line
Line length is 1
../testen/hyphen.gro:11: backtrace: while loop
../testen/hyphen.gro:14: warning [p 1, 1.5i]: can't break line
www   mode
www  mode
www mode
wwwmode
wwmode
wmode
mode
mode
modew
modeww






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File Attachments:


-------------------------------------------------------
Date: Sun 26 Nov 2017 06:24:27 PM UTC  Name: attachment  Size: 1KiB   By:
bjarniig

<http://savannah.gnu.org/bugs/download.php?file_id=42491>

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