Bug#813104: Fw: Bug#813104: units: µs and µsecond handled inconsistently

[Stephen Kitt]

Begin forwarded message:

Date: Sun, 31 Jan 2016 08:38:08 -0500
From: Adrian Mariano <rad...@cox.net>
To: Stephen Kitt <sk...@debian.org>
Subject: Re: Fw: Bug#813104: units: µs and µsecond handled inconsistently


That's definitely a bug.  The plural handling for these edge cases is
hard to figure out.  The way it's written is that prefixes longer than
one character are allowed to take plurals, which hides the second when
it's written as "s".

This means that "micros" parses as the plural of micro, which seems
more reasonable than parsing as micro-s.  It also means that "has"
interprets as the plural of "ha" rather than the hecto second.  Not
sure what's reasonable in that case.  

Anyway, the example you found fails because the string length of the
"micron" symbol is larger than 1 in its UTF-8 representation.  The
simplest fix to this problem is this:

--- units.c.orig        2016-01-31 08:28:06.000000000 -0500
+++ units.c     2016-01-31 08:30:08.000000000 -0500
@@ -1984,7 +1984,7 @@
    if ((uptr = ulookup(unit)))
       return uptr->value;
 
-   if (strlen(unit)>2 && unit[strlen(unit) - 1] == 's') {
+   if (strwidth(unit)>2 && unit[strlen(unit) - 1] == 's') {
       copy = dupstr(unit);
       copy[strlen(copy) - 1] = 0;
       if (lookupunit(copy,prefixok)){


On Sun, Jan 31, 2016 at 11:35:02AM +0100, Stephen Kitt wrote:
> Hi Adrian,
> 
> What do you think of this?
> 
> Regards,
> 
> Stephen
> 
> 
> Begin forwarded message:
> 
> Date: Fri, 29 Jan 2016 12:01:17 +0100
> From: Lionel Elie Mamane <lio...@mamane.lu>
> To: Debian Bug Tracking System <sub...@bugs.debian.org>
> Subject: Bug#813104: units: µs and µsecond handled inconsistently
> 
> 
> Package: units
> Version: 2.11-1
> Severity: normal
> 
> units handles "s" for second, "µ" for "micro" as is SI standard. But the 
> combination of the two is not handled correctly.
> 
> For example:
> 
>  $ units µg
>         Definition: micro g = 1e-09 kg
>  $ units µg ng
>       * 1000
>       / 0.001
> 
> And:
> 
> $ units ms ns
>       * 1000000
>       / 1e-06
> 
> But:
> 
> $ units µs ns
> conformability error
>       1e-06
>       1e-09 s
> 
> By contrast:
> $ units µsecond ns
>       * 1000
>       / 0.001
> 
> 
> 
> -- System Information:
> Debian Release: 8.3
>   APT prefers testing-updates
>   APT policy: (500, 'testing-updates'), (500, 'stable-updates'), (500,
> 'stable'), (400, 'testing'), (300, 'unstable'), (1, 'experimental')
> Architecture: amd64 (x86_64) Foreign Architectures: i386
> 
> Kernel: Linux 3.16.0-4-amd64 (SMP w/2 CPU cores)
> Locale: LANG=en_GB.utf8, LC_CTYPE=en_GB.utf8 (charmap=UTF-8)
> Shell: /bin/sh linked to /bin/dash
> Init: systemd (via /run/systemd/system)
> 
> Versions of packages units depends on:
> ii  libc6         2.19-18+deb8u2
> ii  libreadline6  6.3-8+b3
> 
> Versions of packages units recommends:
> pn  python:any  <none>
> 
> units suggests no packages.
> 
> -- no debconf information  

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